Long Tube Header Install

I picked up a pair of the long tube Headman headers from Panoz, and put them on this weekend. To get them to fit, I moved the oil filter canister forward of the alternator, and rerouted the clutch cable. They bolted straight up and had lots of clearance around the frame and steering linage. I've got a pair of 2 1/2" dia. x 24" long Dynamax bullet mufflers to finish the exhaust system. The car goes to the muffler shop tomorrow to get it all welded up.

I plan to have the car dyno tuned after the exhaust system is complete to see if I picked up any power at the high end. My hope is that I've removed some restrictions from the exhaust, and that it breaths better. If I pick up 15 hp, I'll be happy.

During the past month I put the GTRA on a diet. I've removed 60 lbs from the car, and have set up the 30 gal fuel cell so I can run it half full. That should save another 100 lbs. The 160 lbs reduction is about a 6% reduction in the car's weight. It's not the full 200 lbs I was looking for, but it's better than getting heavier. A 5% increase in hp and 6% reduction in wieght should be a noticable improvement in the car's performance.

My first race is March 5 thru 7 at Arroyo Seco. I'm really looking forward to getting back on the track and seeing how the improvements translate to lower lap times. I'll post dyno results once I have them. Previusly the car made 350 ft-lbs and 315 rwhp.

Good info, Jerry. Sounds like a easiest way to go.

Mike

Jerry, am I understanding that you were able to fit the 351 headers onto a 302?

Do you still have the 5.0 in the car? Are these the long tube headers for the 351 from Panoz? Pics?

Too slow, Pomroy. :icon16:

Too slow, Pomroy. :icon16:

Get to work douchebag. :biggrin:

We need pictures of the steering shaft on his car.

Jerry, am I understanding that you were able to fit the 351 headers onto a 302?
Yes, they bolted up nicely. Before I purchased the hearders I asked several people (including folks at Panoz) and they said that port locations and mounting holes are the same for 302 and 351 heads. There is a difference in block deck height, but that didn't seem to cause any difficulties with my installation.

We need pictures of the steering shaft on his car.
I'm gald you guys like one another.... Otherwise I might wonder...

My steering shaft goes way below the headers. There must be 6" of clearance. The header tubes come straight out of the ports and run 12" before they begin to turn downward and get compined into the collector. The car is in the trailer, but I'll try and take a couple pics. The biggest issue is posting them. Gotta go back to the free server and remember my password and such.

If I remember your situation, you have an elevated steering linkage with a sweivel mounted to the frame. I've seen a picture of the set up. My first thought is that if the location of the mount is below the exhaust port, then you might be able to get these long tubes to work.

I just went back and looked at the pic Jim Pomroy took of his steering shaft location. Those long tubes will clear that easily. No problem.

The header tubes as they exits the port come out level with the ground, they done slope down much if anything. They pass under the upper frame tube with about 1 1/2" of clearance. After they exit the frame, then they sweep down to the collector.

Hopefully I get you some pics later tonight. In the mean time I looked at a WC car at Wire Wheel. The pics of the engine showed the way the hearder run fairly clearly. Worht a quick peek.

Blue Streak, do you fly a plane for a living?

That sounds like Pomroy's setup. If you send me the pictures I can post them. Modifying my steering shaft sounds easier than custom headers.

Jim at americanjim dot com

That sounds like Pomroy's setup. If you send me the pictures I can post them. Modifying my steering shaft sounds easier than custom headers.

Jim at americanjim dot com

PM sent with pics. Thanks for offering to post them.

Thanks Jerry!:thumbsup:

http://jmimac351.smugmug.com/Cars/Panoz-Cars-Random-shots/351Header04/789530036_JfHjE-L.jpg

http://jmimac351.smugmug.com/Cars/Panoz-Cars-Random-shots/351Header03/789530011_vqndm-L.jpg

http://jmimac351.smugmug.com/Cars/Panoz-Cars-Random-shots/351Header02/789529932_BPm64-L.jpg

Here's a shot of the 351 headers on a 351...

http://jmimac351.smugmug.com/Cars/Panoz-Cars-Random-shots/image-40134/286764083_xcztG-M.jpg

Just glancing at it without looking at mine I think I just need a rod end and some steering shaft. Plus weld a tab on to mount the lower rod end.

I get to weld! :bananasmi

edit: I just looked at mine and I think I have close to the same amount of clearance that you do even though the steering shaft is mounted differently. My steering shaft is a straight shot from the firewall the to rack. The shaft has ~6" of clearance from the #8 cylinder primary centerline to the shaft. The shaft passes down by the collector of the shorty header. The further forward you go the more clearance there is. Mine has a universal joint right at the firewall whereas yours has the shaft coming out of the firewall and then using a joint further down to make the turn to the rack. I think the advantage to yours is clearance when using shorty headers as I have very little clearance there since mine makes a straight line from the firewall to the rack. With the long tubes I don't think either makes a difference given that the primaries go sideways off the head. Like yours I will have to move the remote filter mount.

I'm glad you shared this as "what to do about headers" was something making me delay doing something. Thanks Jerry.

PM sent with pics. Thanks for offering to post them.

Jerry,
a couple of things you may want to do now that you have the longtubes in. The wiring you have going down the frame above the longtubes and secured with plastic tiewraps needs to be heatwrapped to prevent insulation damage/arcing.

I had this same issue after fitting the custom headers that I made (melted the tiewraps off while running in the shed). What you are likely to find is that if you dont do this the tiewraps will melt off and the wiring will get damaged. This is more of an issue when the car is stationery rather than out on the track.

Kel.

Just glancing at it without looking at mine I think I just need a rod end and some steering shaft. Plus weld a tab on to mount the lower rod end.

I get to weld! :bananasmi

edit: I just looked at mine and I think I have close to the same amount of clearance that you do even though the steering shaft is mounted differently. My steering shaft is a straight shot from the firewall the to rack. The shaft has ~6" of clearance from the #8 cylinder primary centerline to the shaft. The shaft passes down by the collector of the shorty header. The further forward you go the more clearance there is. Mine has a universal joint right at the firewall whereas yours has the shaft coming out of the firewall and then using a joint further down to make the turn to the rack. I think the advantage to yours is clearance when using shorty headers as I have very little clearance there since mine makes a straight line from the firewall to the rack. With the long tubes I don't think either makes a difference given that the primaries go sideways off the head. Like yours I will have to move the remote filter mount.

I'm glad you shared this as "what to do about headers" was something making me delay doing something. Thanks Jerry.

Suck up.

Jim, the pain train is coming.... Wooo-Woooo!!!

:bananadie

http://www.youtube.com/watch?v=vsqjM9AEqlU

Jerry,
a couple of things you may want to do now that you have the longtubes in. The wiring you have going down the frame above the longtubes and secured with plastic tiewraps needs to be heatwrapped to prevent insulation damage/arcing.

I had this same issue after fitting the custom headers that I made (melted the tiewraps off while running in the shed). What you are likely to find is that if you dont do this the tiewraps will melt off and the wiring will get damaged. This is more of an issue when the car is stationery rather than out on the track.

Kel.

Thanks Kel. Great suggestion. I had not thought of the intense heat that will impinge directly on those tie wraps when the headers are glowing red hot. I will get some heat wrap and take care of that this weekend.

I have relocated the clutch cable to get it further away from the headers, and moved some of the insulation to shield the cable and it's sheath from the heat.

This type of help is what makes this forum soooo stinkin' cool. Putting to use the lessons learned by each one of us without having to experience it first hand. Thanks again.

I'm glad you shared this as "what to do about headers" was something making me delay doing something. Thanks Jerry.

No problem. Glad to take this one for the team. You guys have lead the way for other modifications made to the cars, so it is about time I gambled on a change.

Jerry

Took the car to the dyno yesterday. It made an additional 25 ft-lbs of torque for 375 at the rear wheels, and 10 HP for 325. :iceslolan The torque increase was huge between 3500 and 4500 RPM with the peak occuring at 3800. Peak HP is at 5400. The gains completely disappeared after 5000 RPMs, as the old graph overlays the new graph from 5000 up to 6000 RPM. I'm happy with the increase in torque, but I was hoping to see a flattening of the torque curve out to 5500 RPM. The engine ought to pull like a beast out of corners which is good for my home track. I'll just continue to shift at 5700 to maximize acceleration.

Pretty sure there is a restriction in the intake manifold. I'm using the Typhoon intake from Professional Products. It has been ported to match the Canfield heads. I was told that the long runners in the GT style intake manifold causes a stagnation in the runner at higher RPMs. The engine builder suggests an Edlebrock Pro Flow XT manifold to get better flow at higher RPMs.

Nice, damn all these GT-RA's are starting to put out some power! Going to give my Lsx swap a run for the money! ;-)

Took the car to the dyno yesterday. It made an additional 25 ft-lbs of torque for 375 at the rear wheels, and 10 HP for 325. :iceslolan The torque increase was huge between 3500 and 4500 RPM with the peak occuring at 3800. Peak HP is at 5400. The gains completely disappeared after 5000 RPMs, as the old graph overlays the new graph from 5000 up to 6000 RPM. I'm happy with the increase in torque, but I was hoping to see a flattening of the torque curve out to 5500 RPM. The engine ought to pull like a beast out of corners which is good for my home track. I'll just continue to shift at 5700 to maximize acceleration.

Pretty sure there is a restriction in the intake manifold. I'm using the Typhoon intake from Professional Products. It has been ported to match the Canfield heads. I was told that the long runners in the GT style intake manifold causes a stagnation in the runner at higher RPMs. The engine builder suggests an Edlebrock Pro Flow XT manifold to get better flow at higher RPMs.

Jerry, thanks for posting. I am curious about the diameter and length (measure with a peice of string from the header plate just to the start of the merge collector) of the primarys on the GTS headers you have installed. Could you measure these and post the dimensions pse.

I am hoping to get my car on the dyno this coming Saturday so will also post these figures. I am expecting around 375hp/375tq at the wheels as the car was previously around 340/340 with the 5.0.

Jerry, what compression is your engine and what duration/lift is the cam?

Kel.

Jerry, thanks for posting. I am curious about the diameter and length (measure with a peice of string from the header plate just to the start of the merge collector) of the primarys on the GTS headers you have installed. Could you measure these and post the dimensions pse.

I am hoping to get my car on the dyno this coming Saturday so will also post these figures. I am expecting around 375hp/375tq at the wheels as the car was previously around 340/340 with the 5.0.

Jerry, what compression is your engine and what duration/lift is the cam?

Kel.

Kel;
I just closed up the trailer not 10 minutes ago, so getting tube lengths will have to wait until later in the week. Sorry. The tubes are 1 5/8" dia.

The engine is 10:1 compression so I can run pump gas. The cam is a Bullet custom grind with lift at .550" intake and exhaust, duration at 0.050" is 233 degrees intake and 237 degrees on exhaust. Lobe separation is 111 degrees.

Making 375 hp and torque will be real nice. You'll notice that kind of an increase right out of the box.

That's my goal for this motor. I figure that I can get another 25+ HP out of mine with a less restrictive intake. Just gotta get it to breath better after 5000 RPM. I'm looking at the Edlebrock Pro Flow XT. But that's the next mod for later this sumer.

Kel;
I just closed up the trailer not 10 minutes ago, so getting tube lengths will have to wait until later in the week. Sorry. The tubes are 1 5/8" dia.

The engine is 10:1 compression so I can run pump gas. The cam is a Bullet custom grind with lift at .550" intake and exhaust, duration at 0.050" is 233 degrees intake and 237 degrees on exhaust. Lobe separation is 111 degrees.

Making 375 hp and torque will be real nice. You'll notice that kind of an increase right out of the box.

That's my goal for this motor. I figure that I can get another 25+ HP out of mine with a less restrictive intake. Just gotta get it to breath better after 5000 RPM. I'm looking at the Edlebrock Pro Flow XT. But that's the next mod for later this sumer.

Thanks Jerry. When you measure the lengths, have a look and see if the headers are stepped in diameter, I suspect they may be. If they are can you provide initial and stepped diameters (i.e. may be say 1 5/8" up to 1 3/4").

Your power curve is interesting for the amount of cam you are running Jerry (my cam is a custom Comp Cams grind with .550/.565 lift and 224/232 @ .050 but with tighter lobe separation for running with carb).

I would be interested to see how your engine would perform with a carb setup. I suspect that you would also be around 375/375 with the likes of an Edelbrock performer RPM manifold and a good 650cfm carb. Had you considered swapping to carb? Other option would be an Edelbrock Victor manifold but this is likely to sacrifice some low end torque for top end hp and require higher running rpm.


Assume your Canfield heads are around 190cc port volume?

Kel.

Thanks Jerry. When you measure the lengths, have a look and see if the headers are stepped in diameter, I suspect they may be. If they are can you provide initial and stepped diameters (i.e. may be say 1 5/8" up to 1 3/4").

Your power curve is interesting for the amount of cam you are running Jerry (my cam is a custom Comp Cams grind with .550/.565 lift and 224/232 @ .050 but with tighter lobe separation for running with carb).

I would be interested to see how your engine would perform with a carb setup. I suspect that you would also be around 375/375 with the likes of an Edelbrock performer RPM manifold and a good 650cfm carb. Had you considered swapping to carb? Other option would be an Edelbrock Victor manifold but this is likely to sacrifice some low end torque for top end hp and require higher running rpm.


Assume your Canfield heads are around 190cc port volume?

Kel.

Kel;

Finally was able to get to the headers and make the measurements you requested. Sorry for the delay. THe header tubes are 24" long from the flange to the collector. They are equal length. The tube diameter does change. THe first 3" is pressed into a more retangular cross section, and is 1.5" OD, and the remaining length is 1.75 OD.

Yes it would be interesting to run the motor with a carb, and I bet your right that it would be 375 square. But I'm sticking with EFI for now. I'm gonna try a new intake manifold by Edlebrock. IT's a Pro Flow XT. Looks a lot like an LT1 intake. Should flow better at high rpms.

You can certainly run the 351W headers on a 5.0. You may have to move the oil filter etc on the GTRA, but the steering etc. is the same as the GTS etc.

We now run 351W aluminum heads (old set from our GTS) on the stock 5.0 Explorer motor and it runs great with carb and new Performer manifold too. Got tired of the blasted fuel injection running like crap so went simple. Tossed out tons of wires and FI crap. Now same set up as our GTS with carb, MSD 6AN? etc. We were at 235rwhp seems like we gained about 50hp with the head and carb swap.

So yes you can use 351W stuff.

Kevin
GTS and GTRA

Kel;

Finally was able to get to the headers and make the measurements you requested. Sorry for the delay. THe header tubes are 24" long from the flange to the collector. They are equal length. The tube diameter does change. THe first 3" is pressed into a more retangular cross section, and is 1.5" OD, and the remaining length is 1.75 OD.

Yes it would be interesting to run the motor with a carb, and I bet your right that it would be 375 square. But I'm sticking with EFI for now. I'm gonna try a new intake manifold by Edlebrock. IT's a Pro Flow XT. Looks a lot like an LT1 intake. Should flow better at high rpms.

Jerry, the primary length of the GTS header is interesting at 24" for the 5.0. 24" is to short to make optimal power & torque at reasonable rpm (see Performance Tuning in Theory & Practice by A. Graeme Bell page 115).

This length primary for a 5.0 with the sort of cam duration we run (approx 220 - 235 deg at .050") is designed to make peak power up around 7500 - 8000rpm. The primary lengths on my headers are around 36" for this reason, to get the peak torque and hp down around 4500 - 6000rpm.

It will be really interesting to see where peak torque and hp end up when you change your manifold over. I expect that they will be at higher rpm than at present.

I must say that I am loving the torque of the 347. Corners that we used to take in 2nd gear we can now take in 3rd and the car will still step out (slide) if to much throttle is used. Makes for a far nicer package to drive. I am finding myself short shifting a lot now as there is no need to rev the engine due to the amount of torque on tap.

Kel.

Kel,
Remind me again, what are the primary diameter on yours and the collector diameter and length before they merge.

Thanks,
Mike

Kel,
Remind me again, what are the primary diameter on yours and the collector diameter and length before they merge.

Thanks,
Mike

Mike, 1 3/4" dia x 36" long primaries (measured to the merge section of the collector), 3" dia collectors, merge into single 4" dia pipe prior to 4" superflow muffler (3.5" modified to 4") and then 4" pipe to outlet in std location on RH side of the car.

The step on the GTS header will most likely help to broaden the torque range I suspect but still a short primary for a 5.0 working in the rpm range that most of us are using.

Kel.

Kel,
Thanks. Tom and I are having a couple of sets fabed up using your example as inspiration. Hope to have some fixtures as a result so they could be more easily reproduced. We have your photos and wanted to be careful not to mess up the critical dimensions. How long are the three inch collectors? Does that matter? Suppose we went to a stepped design, how would that effect the primary length and where should the step from 1 5/8 to 1 3/4 be placed. Idea is same 6000 and below power band with 5.0 stroker and roughly the same heads, carb and cam as you are running. Thanks for the guidance.

Mike

Kel,
Thanks. Tom and I are having a couple of sets fabed up using your example as inspiration. Hope to have some fixtures as a result so they could be more easily reproduced. We have your photos and wanted to be careful not to mess up the critical dimensions. How long are the three inch collectors? Does that matter? Suppose we went to a stepped design, how would that effect the primary length and where should the step from 1 5/8 to 1 3/4 be placed. Idea is same 6000 and below power band with 5.0 stroker and roughly the same heads, carb and cam as you are running. Thanks for the guidance.

Mike

Mike, the collectors are 6" long with the tapered section being 4". The collectors are Hedman items. I have an excel spreadsheet which has all the fomulas in it that I used to calculate critical diameters and lengths of the system. Happy to share this with you. All of the formulas are straight out of the A Graham Bell book that I mentioned.

Note that I built my system to work with a 347 so the 1 3/4" primaries and 36" length are tuned for an engine of this capacity and 5600rpm to suit endurance racing. By using the formulas you can play with critical dimensiosn to suit your application.

Regards using a step in the primary pipe, I have not experimented with this. I have done some reading on the theory of stepped pipes and there is a lot of evidence to support using this approach (they use multiple steps in F1 headers). I expect that using say 1 5/8" stepping up to 1 3/4" will provide a slightly lower peak torque rpm and a broader torque curve. Having said that the 5.0 and more particularly the 347 have a very flat torque curve in the configuration that we use them so hard to say what gains you will achieve. I suspect that the stepped configuration would have more effect when longer duration camshafts were used and low speed torque was affected.

Drop me your E address by PM and I will send you the spreadsheet Mike.

Kel.

Me too me too.

[email protected]


Thanks

tom

Mike, the collectors are 6" long with the tapered section being 4". The collectors are Hedman items. I have an excel spreadsheet which has all the fomulas in it that I used to calculate critical diameters and lengths of the system. Happy to share this with you. All of the formulas are straight out of the A Graham Bell book that I mentioned.

Note that I built my system to work with a 347 so the 1 3/4" primaries and 36" length are tuned for an engine of this capacity and 5600rpm to suit endurance racing. By using the formulas you can play with critical dimensiosn to suit your application.

Regards using a step in the primary pipe, I have not experimented with this. I have done some reading on the theory of stepped pipes and there is a lot of evidence to support using this approach (they use multiple steps in F1 headers). I expect that using say 1 5/8" stepping up to 1 3/4" will provide a slightly lower peak torque rpm and a broader torque curve. Having said that the 5.0 and more particularly the 347 have a very flat torque curve in the configuration that we use them so hard to say what gains you will achieve. I suspect that the stepped configuration would have more effect when longer duration camshafts were used and low speed torque was affected.

Drop me your E address by PM and I will send you the spreadsheet Mike.

Kel.

Me too me too.

[email protected]


Thanks

tom

Tom, sent this morn. Kel.

Tom, sent this morn. Kel.

Kel,
Thanks. If Tom's got it then I've got it (we're joined at the Panoz).

Mike