Hp Search ...

Good Morning , I ran my GT-Ra for 15 track day events at BIR last season & have the need for more H.P. ; I know that this is a strange phenomenon reading the other treads ... In my case ; I'm looking for a smaller step & remaining in a predictable / reliable platform to preserve the fun level , budget & new marriage ... For Christmas , Kimberly ( wife ) snooped through my Summit Catalog where there was a few thoughts marked w/ post-its ... Santa via UPS brough a Edlebrock 75 mm T.body ( anniversery gift ) & a Trickflow -Track Heat Intake w/ phenolic heat spacer that was under the tree 5 days later for Christmas... Looking for some input about utilizing the 5.0 mustang world of " go-fast " parts ...
Thanks / Paul W. / Duluth , MN.

Hi Paul,

Removing the EFI stuff completely will give you the biggest gain. We have customers that have 5.0 Mustangs and JUST removing the EFI and adding a dual plane intake and a carb they pick up 30 h.p.

IF you are after real power, swap out the heads for some of the new edelbrock aluminum A sedan heads (a great value). Shim the springs to 140# and add a solid lifter cam and roller rockers with about 246/254 and .500 lift (.500 lift so your valve reliefs won't be an issue). That cam seems big for the 9.5 to one compression ratio...but its not.

You can get these cams from A/Sedan racers pretty cheap as they are always swapping them out. You'll have great throttle response and good power, the engine will pull to 7000 rpm and you'll get 400 flywheel h.p. out of it even with your shorty headers.

Thats the power it needs in that car.

This is a pretty standard combo that will run low 2:30's at Sebring at 3200 lbs and 140 mph and 2:10's at Daytona in the heat of the summer. You'll be faster than that yet.

Your trans and rear end are waaay overbuilt for the job. So don't worry about them.

We use a stock World Class T5 (cheap tranny) and a little 8.8 rearend in our A sedan car. Never broke a thing.

Any engine builder can assemble this combo "IN" your car pretty fast. It's a pretty good idea to use a builder so they degree in the cam and clay the valve reliefs "just in case".

Patrick James
PRO SYSTEMS

Paul... we've elected to go with an Ed Curtis (Flow-Tech Induction) spec'd cam and AFR 165s etc. Ditching the EFI and using a Pro-Systems road race spec'd carb. We're shooting for 320-340 rwhp out of the 5.0 and Swapping to carb and aluminum heads should drop around 70lbs from the car.

Hi Paul,

IF you are after real power, swap out the heads for some of the new edelbrock aluminum A sedan heads (a great value). Shim the springs to 140# and add a solid lifter cam and roller rockers with about 246/254 and .500 lift (.500 lift so your valve reliefs won't be an issue). That cam seems big for the 9.5 to one compression ratio...but its not.

You can get these cams from A/Sedan racers pretty cheap as they are always swapping them out. You'll have great throttle response and good power, the engine will pull to 7000 rpm and you'll get 400 flywheel h.p. out of it even with your shorty headers.


Hi Patrick, I am interested in what the power curves look like for the suggested combo. At what RPM is the peak power of 400 made, what is peak torque and at what RPM is this made? Would be great if you could post a pic of dyno curves if possible.

Thanks, Kel.

Unfortunately, specific info like that is held pretty tight as these combinations are used in in our highly competitive American Sedan class.

We used our car to develop the carburetors and test engine packages and parts for this class for a Ford Sponsored team and have won the National Runoffs two years in a row and the 2008 SCCA Triple Crown with these highly developed combinations. We hope to make it three in a row this year.

So exact info is guarded pretty tight.

We worked with an Engine builder Ken Felice ( www.feliceracing.com ) You can contact him directly via their website and see if he will release specific info to you, but I can/will/should only offer general info that A/Sedan racers already know so as not to lose any power advantage.

But this general info is enough to do what we want to do here anyway.

None of us need to hire a Formula One team to test spin valvetrain components like these guys do.

We just need a little more power.

Patrick James
PRO SYSTEMS

Unfortunately, specific info like that is held pretty tight as these combinations are used in in our highly competitive American Sedan class.

Ah, the mysterys of motor racing huh!!

One other thing that I am interested in though Patrick, how durable have you found the stock 5.0 bottom ends? I have been warned by several Ford 'experts' in New Zealand not to spin the engine abover 6000rpm if at all possible due to weak crank and block. I have been told the engine is a hand grenade at my current power level of 400hp (at 5700rpm) even though I am restricting rpm to 5800.

Cheers Patrick, Kel.

We bought a car that came with a short block that was bought off a cheap internet rebuilding company for $900.00.

It was the late model 5.0 stock block with forged pistons and stock rods but with good bolts and still had the fat 50 oz crank.

We regularly shifted it at 6600 rpm with no issues at all when we had to run our GT40P heads (new aluminum heads were not legal then).

If you are going to go beyond 7000 rpm a lot, zero balance the crank that helps the block stresses tremendously. Also take it easy on the up and downshifts. Slamming it into the next gear will make you only minutely faster. But is hard on parts. Slow down just a little on the clutch release speed a little, slip it for 1/10th of a second to take up the slack before full engagement for both up and downshifts. This keeps from shocking the crank and splitting the block. I never got the clutch hot doing that. I never broke a transmission or a rear end either.

But in most races you only need to whip it hard for the first few laps and get a good lead :grinyes: ... then back off on the shift rpm a little and take your deserved win.

Patrick James
PRO SYSTEMS

Thanks... I'm not sure if I want to dive into the heads ... Does any one have a insight to the performance of the parts combo that Santa brought me ??? If I go for a carb / manafold ; can you guys give me a manufacture for the manifold & carb size ... Other associated question w/ the carb approuch ,does the cars computer need to be re-mapped & do i need a tool box full of jets to run in 40 to 110 degrees w/ all ranges of relative humidity... Speaking of weight , I 've heard the PI system should be replaced w/ analoge gauges , not using the tracking / data collection feature & would rather glance at my engin stats ... :screwy:

Thanks... I'm not sure if I want to dive into the heads ... Does any one have a insight to the performance of the parts combo that Santa brought me ??? If I go for a carb / manafold ; can you guys give me a manufacture for the manifold & carb size ... Other associated question w/ the carb approuch ,does the cars computer need to be re-mapped & do i need a tool box full of jets to run in 40 to 110 degrees w/ all ranges of relative humidity... Speaking of weight , I 've heard the PI system should be replaced w/ analoge gauges , not using the tracking / data collection feature & would rather glance at my engin stats ... :screwy:

Cant comment on injection output, I will leave that to those with more experience with the injected combo.

Regards a carb and manifold combo, if you are going to use in the 2500 - 6500 rpm rev range as I suspect you will want to, then an Edelbrock Performer RPM (or similar) and a 600 - 650 cfm carb is probably about right. You will not need the computer anymore and you will need to change out your distributor.

Your engine will have around 220 - 230 hp now, changing to new manifold and carb will probably get you up to around 260 - 270 hp, maybe a little more. The heads & cam are where the power is really made. By stretching your budget to a set of aluminium heads and a cam with more duration/lift, you will get up above 350hp.

I have just been through this exercise. Key engine parts cost was around USD$2,775. You can spend a bunch more on super dooper parts if you choose to but you probably wont get much under this figure using reasonable quality gear. Engine made 400hp/390 torque at the flywheel on the stock bottom end.

PI system Vs analogue is really a matter of personal choice, if you have the alert parameters set correctly on the PI unit, it will flash and warn you of any over temps or pressure issues. Just a matter of getting used to this type of system or ditching it if uncomfortable with not being able to scan all different parameters at the same time.

I went with Canfield heads, the Ford Racing B-303 cam, a copy of the Edlebrock EFI intake manifold, 75 mm TB, and roller rockers. I think I'm close to 350 HP at the motor. The bottom end of the motor is stock. I shift at 6000 to 6200 RPMs. As far as reliability/durability, I missed a couple of up shifts at red line during races (got 3rd instead of 5th), and the thing held together. I'm sure I hit 8000 with the misshift.
I went to anolog gauges just last weekend. I couldn't get used to the PU Dash (Freudian slip). For me it was very hard to see RMP, or critical temps during the heat of battle. The install of the gauge pack was straight forward, and it looks nice with the three pack sitting below the large analog tach.
Jerry

Good Morning & thanks again ... Jerry , As you removed the PU system , did you just start at the dash unit & un- strap / un- tape to remove the complete wire harness or use the harness for connecting the gauges ???
Did you repete every PI function or drop some of the outer perameters , ie ... fuel pressure , oil temp. , speedometer ???
Please post a few pictures & note any problem areas ...
Paul / Car 46 ; Chassis 37

Paul, save yourself some time and contact Ed Curtis at Flowtech www.flowtechinduction.com

He's done a lot of windsor engine setups for mustangs and knows these intakes and what works inside and out. Agree to buy a cam from him and you'll get to access his brain to spec out the setup (which heads, mass air meter, injectors, etc) and custom design a cam for it. The intake you have is fine although I'm not sure Ed will want you to use the spacer.

As for the PI thing, it's sort of like trying to read my BlackBerry while driving. Have you ever wired a car? If you've never wired a car you might want to just leave it and add a few gauges: Tach, oil temp, oil press? Maybe use the PI to access water temp, fuel pressure, and volts. If you're staying EFI I'd definitely want to see fuel pressure.

Or, when this comes out for small block Fords in the spring it could be interesting... :iceslolan

http://www.edelbrock.com/automotive_new/mc/efi/images/3527.jpg

Removing the EFI stuff completely will give you the biggest gain. We have customers that have 5.0 Mustangs and JUST removing the EFI and adding a dual plane intake and a carb they pick up 30 h.p.


PRO SYSTEMS

Patrick, for real? I was thinking of waiting another year to do a whole engine swap out, maybe something like Brian G (but not nearly so powerful) or an LS1 like Eric. If I can get 30hp now and reuse the intake and carb with the next engine, that would be outstanding. Am I understanding that correctly, or is there more to it? I know, there is always more to it!

I know crazy but its true, carbs make more power than EFI. I have yet to run into a situation where that is not true and regularly in some of our drag racing classes, our carbureted cars are forced to carry a 100 lb penalty versus an EFI counterpart.

But let me give you a road racing example: In 2003 we designed a carb based on the rules packages written for the Rolex 24, that not only qualified number one in class. The car (#40 Corvette driven by Justin Bell powered by CRD) was the number one qualifier at the Rolex 24. Ahead of the Daytona Prototypes and everybody. Here sets this Justin Bell CRD powered Pro Systems carbureted Corvette.

Click this link and arrow down to January and February of 2003 for Test session information and Qualifying results.

http://www.prosystemsracing.com/news.html

Well the Rolex 24 folks would have none of that and would not allow Justin to lead the field to the Green and made Justin start at the front of his own class. They immediately re wrote the rules regarding carburetors in the series (essentially giving them such a huge disadvantage that it wrote them out of the series).

It was a great last in your face hurrah for carburetors (man did we have some power).

Although carburetors still dominate in SCCA GT-1 (we won this years Runoffs in GT1) and in A/Sedan (we won the Runoffs there as well and the 2008 SCCA Triple Crown..so it was a good year).

But alas carbs are getting few and far between in road racing. Folks find them difficult to understand when they are malfunctioning. A laptop is how people are used to running their lives. It's a shame too, as they are simple and reliable and you can repair them in seconds if there is a component failure or change them quickly if there is an engine combination change.

I build carbs for road racing as more of a passion. I love road racing. but it is merely 2 percent of our business. Drag racing where carbs dominate thefields is our player by far.

Zora Duntov once said "If a guy came along AFTER E.F.I. and invented the carburetor, he would be heralded a genius".

Heres a link to some insight into why carbs make more power.

http://www.pro-system.com/scoop92102.html

Patrick James
PRO SYSTEMS

I build carbs for road racing as more of a passion. I love road racing. but it is merely 2 percent of our business. Drag racing where carbs dominate thefields is our player by far.

Patrick James
PRO SYSTEMS

Patrick, when I inquired in another thread about modifications you do to carbs the gist I got from your answer was that you didn't get into that much and it was left for the specialty carb shops to tune for one's combo. How does one get to be part of the 2% of your business? Is that just the special projects you get involved in? I hear ya about simplicity. I have a set of Weber 48 IDAs that have been sitting on my bench for a long time waiting on me to put them on my cobra. Well, maybe not so simple.

Good Morning & thanks again ... Jerry , As you removed the PU system , did you just start at the dash unit & un- strap / un- tape to remove the complete wire harness or use the harness for connecting the gauges ???
Did you repete every PI function or drop some of the outer perameters , ie ... fuel pressure , oil temp. , speedometer ???
Please post a few pictures & note any problem areas ...
Paul / Car 46 ; Chassis 37

I haven't removed the PU Dash, I just added the three analog gauges. I did remove the oil temp sensor for the PI Dash, and installed the sensor for the analog oil temp gauge. The PU Dash only showed oil temp after it got above 190 F, so the low end temps were shown as "LOW." With the analog gauge I get temps between 150 and 350 F.

The advantage of the PU Dash is that I can still get fuel pressure, speed, etc. Because I still want to look at these parameters, I'm keeping the system operational this year. If I don't use it, then I'll get ride of it next year.

Jerry

Patrick

Do you have a shop or do any tuning down here in Florida?

I haven't removed the PU Dash, I just added the three analog gauges. I did remove the oil temp sensor for the PI Dash, and installed the sensor for the analog oil temp gauge. The PU Dash only showed oil temp after it got above 190 F, so the low end temps were shown as "LOW." With the analog gauge I get temps between 150 and 350 F.

The advantage of the PU Dash is that I can still get fuel pressure, speed, etc. Because I still want to look at these parameters, I'm keeping the system operational this year. If I don't use it, then I'll get ride of it next year.

Jerry

If you unplug your wheel speed sensor the dash will stop going into record mode and won't switch from the screen you have it set on. Of course it won't give you the alarms or speed either. It's not a very intuitive piece for sure. I wonder who's brilliant idea it was to not give it the option of turning off the record/exit speed mode while on track.:screwy: I'm afraid to go to analog guages as I've gotten used to never looking at the dash for meaningful information.:cwm27:

A good compromise might be some Spa guages that have programmable alarms built in. http://www.spatechnique.com/product_pages/index.cfm

My apologies jmimac351,

I must not have been clear on our road racing programs. We do them, we love doing them. But they are few and far between.

The nice thing is the end purchaser gets some pretty good technology, funded by some pretty high end teams with big budgets. BUT, other than NASCAR (which is where most of this money come from) the market in road racing is limited to just a few classes. So spending advertising dollars in SCCA or other road racing type magazines to generate only a few sales is not money well spent.

Road racing and carbs may see a resurgence. A good friend of mine, Jim Derhaag has resurrected Trans AM so now we'll get that GT1/muscle car sound and raw power back into racing to revitalize the people in the world. Maybe get some TV time in the future and get folks interested in Trans AM again. World Challenge is fun but they are not scary beasts like Trans Am/ GT1 cars.

Electronically controlled(traction control and ABS) and restricted engines that can't spin the tires pleases very few people in the stands. They want to see beasts that are out of control, (cars that are spinning the tires and locking up the brakes) attempt to be controlled.

In drag racing they've proven this true time and time again. In drag racing folks like to see carburetors and NO TRACTION CONTROL. It's why NHRA keeps those rules in place in Pro Stock. It draws fans.

But as cars get more and more electronic, the classes seem to run for a bit and then fade away.

So we'll see how Trans AM pans out. Those cars have that good formula. They are primitive beasts and scare you cuz you never know what they are going to do. Thats why I like watching them race.

Also Gatorac,

We have a shop in Florida, buts it's only where we keep and maintain the test cars. Most of the development is done in Michigan and then flown down here for final track testing.

Patrick James
PRO SYSTEMS

That's good to know, thanks Patrick. It's hard to find anyone to talk to about a road racing carb setup and I guess that's why you start looking at other options. Several of us down here are thinking about what we're going to do when the time comes for more hp. Pomroy instructs with Chin Motorsports down here in Florida and I'm going to run with them quite a bit going forward - mostly at Sebring. Maybe we can convince you to come down for a drive. :icon16:

I appreciate the invite to CHIN.

When I first got my SCCA license (I got the SCCA license so we could test products for a Ford sponsored team and develop carbs for their program) I applied to Chin and was rejected.

I told him a bit about my background etc.... Karting championships, NHRA and IHRA Licenses, even won my Panoz school race by a mile over 20 other guys. He would have none of it. Shot us down.

We just wanted to get a little track time on our A/Sedan car before we went to our first race, it didn't happen. It turns out we didn't need it. The car was great right out of the box, qualified number one and won the race in a field of 6 cars at Sebring "first time out".

I raced for two years and I never touched another car. I got tagged in the back and alongside by a few guys, but kept my nose clean. Always drove safe (even winning at over 130 mph in heavy rain on slicks).

But I still remember being bummed at how quick the CHIN guy shot me down. He didn't know me so I understand. I thought it was a big loss for us at the time (we thought we needed track time), but we ended up good "out of the box".

I guess he gets a lot of newbies asking to participate and the guys that race out there are driving some pretty pricey cars (ferraris, porsche etc....) So I understand now. I have a GTS Viper I've done some work to that I was thinking of driving over there... I may take you up on that offer.

Now with a spotless SCCA record, an SCCA Championship trophy and a Sebring Track record I should be good.

The guy has to play it safe I understand.

BUT just in case, keep this record of accomplishments in your file if I need to plead my case again, it'd be nice to have a guy on my side.

Thanks. :wink:

Patrick James

Zora Duntov once said "If a guy came along AFTER E.F.I. and invented the carburetor, he would be heralded a genius".

Patrick James
PRO SYSTEMS

I'm sure anyone who has worked with the Corvette mechanical fuel injection would say the same.......

Patrick, I've run with Chin once several weeks ago and it was very organized. They don't take chances, that's for sure. I would think you'd be fine now to go for a check out ride. Another option is SAFE which has worked out very well for me with it's open track format. I think given that SAFE is an open track format it intimidates newer guys and you end up with more experienced people showing up? Either way, if you have money and a helmet you're all set with SAFE. I've had a great time with both. :smokin:

By the way, when you do a road racing carb are you setting it up exactly for the application as it relates to metering, etc. or does "road race" have more to do with the components - road race floats, etc.? I'm asking from the standpoint of bolting a carb onto the stock block / heads and then growing into it with heads, cam, etc. Not sure if what you would normally do would require changes other than jets according to those combos.

Hey Paul, looking around I've found one way to piece this efi stuff together is to search posts on mustang / ford sites by the more experienced vendors on those sites. You can search by username Ed Curtis or Jay Allen on www.corral.net. Those guys design cams. Also search username Jay Allen on www.sbftech.com His website is www.camshaftinnovations.com There is a lot of noise on the corral website that you have to sort through. Or like I said, call a cam guy and they will square you away and save a lot of time.

Hi Stu, thanks for dialing my suspension in this weekend.

Jerry ... I'm going to go with the EFI parts that Santa brought me & install a set roller rockers on the stock GT-40P heads ... Who's did you install ; 1:6 or 1:7 & are they stud or pedistals ??? Car is in storage & I'm recovering from hip reserfacing , but still can order parts !!! Your help would be greatly appreciated ... Paul / #37

Jerry ... I'm going to go with the EFI parts that Santa brought me & install a set roller rockers on the stock GT-40P heads ... Who's did you install ; 1:6 or 1:7 & are they stud or pedistals ??? Car is in storage & I'm recovering from hip reserfacing , but still can order parts !!! Your help would be greatly appreciated ... Paul / #37

Hope your recovery from surgury is quick.
Sounds like the increase in HP from new EFI parts will be nice!
I put in a set of Scorpion 1.6:1 stud mount roller rockers. They came with the heads that I purchased. I think the studs were 7/16" dia.
I also changed out the cam to a Ford Racing B-303 bump stick. When I checked piston to valve clearance, it was too close for comfort, so I had to cut more on the valve releif on the top of each piston. I was able to get over 0.06" clearance after a little grinding. The reason I mention this is because I think with a stock cam you might get away going with 1.7:1 rockers, but in my case with the cam change it probably would have created an interference with the piston and intake valves.
I'm sure there are several other people out there in 5.0 land that can tell you (much better than I) if going to 1.7:1 rockers will work for your motor. If you can check internal clearances, you know for sure.
Best of luck.
Jerry

Paul,
The oldest and cheapest trick to get some more cam on the stock 5.0 is 1.7's. You won't have any clearance problems. Pedestal mount on the 40P heads. If you change heads to something no bigger than 1.90 intakes, still no problem. You can even go a little bigger on the cam with after market heads and still use the 1.7's so you are not likely throwing your money away now. If you find you want to go with larger intake valve heads, say 2.02's or smaller combustion chamber, or a bigger cam, fly cutting the intake releafs at head change time only takes an hour or two and you can do it yourself. I am currently running the Edelbrock Performer 5.0 heads (1.90 intakes), the E303 cam and the crane 1.7 pedistal roller rockers on an otherwise stock '95 5.0 block. It gives me .527 lift (up from .498) and no fly cutting was necessary. The 1.7 roller rockers I got were the ones Crane made for Ford the '93 Mustang Cobra. I figured they would last a long time. Crane still makes them.

Mike

Thanks for the 1:7 insight ... I still have another caveat ... This engine must have had a different cam installed some where down the road ; it has a distinct lobe at idle ; nothing crazy ; but there !!!
Any one have a simular experience & have measured their cam ??? Still dont want to pull the heads ; just a $$$ thing ...The only clues I have are this car was # 42 / chassis #37; John Leverette @ Panoz believes its a Texas car & Hayse at Wirewheel stated this was their promotional car ... Thanks Guys / Paul ...

Thanks for the 1:7 insight ... I still have another caveat ... This engine must have had a different cam installed some where down the road ; it has a distinct lobe at idle ; nothing crazy ; but there !!!
Any one have a simular experience & have measured their cam ??? Still dont want to pull the heads ; just a $$$ thing ...The only clues I have are this car was # 42 / chassis #37; John Leverette @ Panoz believes its a Texas car & Hayse at Wirewheel stated this was their promotional car ... Thanks Guys / Paul ...

This is just a guess, but an Atlanta car I know of has a B303 FRP/SVO cam. It may have come from the school with this cam. If the motor was otherwise unmodified, this could be a good bet.

You can probably confirm which cam or at least narrow it down by checking lift. Pull a valve cover and use a dial indicator on the rocker at the point directly over the valve tip contact point. Zero it at closed position of the valve and turn the motor over by hand until you get max lift. I have some one push the car in second or third gear a few feet while I look at the dial indicator. Once you are close to max lift you can rock it back and forth to confirm. Since the rocker rocks (dah), the point of contact changes a slight amount so the measurement is not exact, but close enough to be compared to the specs. I believe it will probably be a little less than actual lift. If you want a more exact measurement, just pull a rocker and use the dial indicator on the exposed push rod tip. Since it is rounded, put a 1/4 drive socket that fits snugly over it and read the movement on the socket bottom. When you get this measurement multiple it by 1.6 (the rocker arm ratio) and you'll have valve lift or you can just directly compare it to the lobe lift spec listed by Ford. When I did this push rod measurement with an E303 cam, the measurement was accurate to .001.

Since these are bolt down rockers, all you need to do to reinstall is get the proper torque applied to the allen head bolt.

Since the FRP/SVO cams were the cheapest, most common upgrades for unmodified/mildly modified 5.0's it's likely one of those. The mild lope you discribed points to the B303 or E303. You can get all the specs for these on the FRP site http://www.fordracingparts.com/download/charts/85.pdf

If the measurement doesn't line up with an FRP/SVO cam, you could compare it to other mild aftermarket common offerings. You only need to measure one valve to see if you have an FRP/SVO cam as all the Ford hydraulic roller cams are the same lift for both intake and exhaust. If it doesn't match up with one of those, there may be some of the mild aftermarket ones that do have different intake and exhaust lift (I don't really remember). I believe this is usually only seen on more agressive grinds, not suitable for a stock valve train.

Hope this helps.
Mike

Good Morning Mike ... I down loaded the cam spec. sheet & will be calling Ford's Tech. Line for complete head specs today ...
1-800-FORD778 / option #2 ; If my current cam is a B or E 303 do you think the 1:7's are a go and are the existing valve springs OK w/ the additional travel / compression ??? Thanks / Paul W.

Good Morning Mike ... I down loaded the cam spec. sheet & will be calling Ford's Tech. Line for complete head specs today ...
1-800-FORD778 / option #2 ; If my current cam is a B or E 303 do you think the 1:7's are a go and are the existing valve springs OK w/ the additional travel / compression ??? Thanks / Paul W.

Yes, I'm sure they will be. You should double check with Ford Tech, but in a prior life I managed a Ford oriented performance shop where we routinely installed the 1.7's with the B303 and never had to flycut the pistons or change springs. As I recall in the early '90's, Ford had a more aggressive cam than the B with about .540 to .560 lift and maybe 230 duration. Springs and flycutting were required to use the 1.7's with that one. Apparently not enough were sold with all that hassle and they dropped it. I have recently installed 1.7's on a '95 Mustang 5.0 motor with the E303 cam and Edelbrock Performer 5.0 heads (1.60 exhaust and 1.90 intakes) with no issue. Duration is 220 and valve lift is .527 with the 1.7's. Runs great. Small increase in the idle rumble (great sound), gained slightly in mid and top end at no noticeable bottom end loss. With the stock heads the net gain on the top should be noticeable and midrange should pick up as well.

The stock valve springs should be fine if they are close to spec. If you want to check them, pull a couple and have them checked by a shop. You know the rope trick to keep the valves seated? I don't use the compressed air technique, too prone to problems. The stock heads don't flow enough to make added power above 5500 or so, the 40p's might do marginally better. A stock 5.0 peaks horsepower at 4800-5200, but the factory rev limit is 6150 on the mustang, don't know on Explorer version, but it's set below any spring issues. Shift at 5500 and you'll have no issues with stock valve springs and that will be about or just above where your peak power is. An occasional minor over run should be OK. The rev limiter in the computer helps, but nothing is going to help with a 5th to 2nd down shift, 1.6's or 1.7's. The most noticeable gains will be 3500 and above. Expect maybe 8-10 hp or a little more and it's useable.

If Ford has any conflicting info, let me know so I get it right. I have some historical parts package lists we used to use in the early '90's I can dig up and reference in the case I've had a major case of brain mush. You might find the Ford tech guys don't have much specific on this combination as they want to sell heads more than rockers as well as being more current in mod motors.

I found those Crane 1.7's on ebay new for about $180. I wouldn't buy them used as they might have been in a cobra motor for 10 to 15 years. I don't think they are economically rebuildable.

Not to change the subject, but if you have any issues with cracked exhaust manifolds, replacing them with a set of shorties will gain you about the same as the 1.7's, maybe a couple more hp. I mention this as the stress on these is greater than in the passenger car due to the exhaust routing and if you ever need to replace them, it's a performance upgrade for not much extra cost, especally if you can round up a gently used set. Makes a nice compliment to the cam and rockers with stock heads. The three together would net about 35 hp or more, with a broad power range. You could be at about 280+ at the flywheel with the intake and the rest, 240 + rw. You should dyno for a good baseline prior to changing heads. With the these changes, a good set of heads, like AFR 165's, and tube headers, like the GTTS Hedmans, could net 40 hp as a next step, without touching the block. I'd bet you'd be pushing 300 at the wheels versus 200 for the bone original set up. My guesstimate only, but it would be very instructive to know as you progress.

Mike

Mike , Ford Racing stated that the following piston / valve clearence is required ; .080 intake & .100 exhaust ... They recommended pushing the valve down to contact ; then do the math up from there ... plus , never over .500 w/out verifying ... This is a have fun / go drive thing for me ... I'll be safe & go w/ 1:6 's :banghead: Second thought !!! Measurure the push rod throw ; do the math ... Compair to the .500 " no-check warning ... Call the bubble ... I wish we had more insight to the 2000 Explorer engins that the GT-Ra's have to compair to your / Mike's early Mustang engines experiance ... If I'm Chicken SH** ; let me know !!! :shakehead

Paul,
The clearance numbers are good. Same as I recall. I believe I checked my motor the way they stated and had plenty with the 1.7's. The Explorer motor should have the same pistons and chamber volume, so the clearance issues should be identical. But I wouldn't take a chance unless I had expert witness that it is the case.

It is a bit of a hassle to check the actual clearance with heads on, but it would give the certain answer. If you decide to do it, remove the rockers on the intake and exhaust valves on number 1, rotate the motor to number 1 at top dead center (TDC) or pointer to the dampner zero degrees mark, remove the springs from number 1's intake and exhaust valves and reinstall the rockers. Allow the valves to ease down to touch the top of the piston and measure the clearance between each rocker tip and the valve stem tip. Remove or back way off the rocker mount bolts so as not to collapse the hydraulic lifter as you turn the motor over one turn and likewise secure the values in their seated (upward) position so they do not drop down into the chamber as you rotate the motor. Rotate the motor through one revolution back to TDC. Reinstall or bolt down the rockers and repeat the clearance measurements. The least valve to piston clearance occurs at the TDC positions so if these clearances are all greater than those stated by Ford, you are good. You can reassemble. If you do this using the original 1.6's before you spring for the 1.7's (a good idea), then you need to reduce the measured clearances based on the greater lift the 1.7's will provide. Multiply the measured clearance by .9412 (1.6/1.7). This gives you the appropriate reduced clearance as if you had a rocker ratio of 1.7 rather than the 1.6. Probably need some help to manage the turning over of the motor and keeping the valves up.

If you think about it, that's a lot of work (couple of hours the first time) for a difference of 8-10 hp, plus the cost of the rockers. Under the circumstances, I'd probably stay with 1.6's, too.

I do have a set of bolt down Motorsport 1.6 roller rockers (blue annodized) I don't need. They had less than 10K miles (probably more like 4000 miles) of use in a street car that never turned over 4200 rpm (screwed up rev limiter, it's a long story). They are in tight, new condition. One or two have a mild rub from the valve cover. The steel covers we have shouldn't rub like the aluminum ones did at the front or rear bolt bosses. I have a partial set of shims that come with them, but they were installed without any and worked great. You can stay with the factory rockers, but the roller rockers reduce friction and oil temperature in the motor and valve train wear. No measurable hp gain that I know of in mild applications. It's really a minor effect. If your interested, PM me: $50 plus shipping.

Mike

Mike , Yes I'm interested ; I'll take the friction loss & additional stabilization to the valve train by installing the 1:6's that you have ... Every thing points to pedistal type ... I'll get to the car this week end to verify ... Call me / 218.393.4848 to do the deal ... :iceslolan Duluth ,MN . for estimating the shipping ... Thanks / Paul

I'll try to call tomorrow or Sunday. UPS is best so I'll find out about shipping Monday.

Mike