Looking for feedback on GT40P Heads

[1Quick91]

I have a chance to pick up a set of GT40P heads with 5 angle valve job, .550 spring kit, Larger 1.90x1.60 Stainless intake and exhaust valves with guides for $700.00 brand new.

Would like to know what the board thinks of these heads. I am thinking of replaceing my GT40 heads and have been told that the GT40P flow much better and top end would be much improved as well.

My GT40 Heads are using 1.85 intake and 1.54 exhaust with .500 spring kit. The heads have been extrude honed though.

Also what is this heart shape combustion chamber that the GT40P heads have and the GT40 do not.

What is a 5 angle valve job? I have heard of a 3 angle valve job but not a 5 angle.

[StangNut86]

first, what kind of motor and what displacement will these heads go on?

the larger intake and exhaust valves will help you, but only if you have a came that's suited to these heads and your application (turbo, blower, nos, etc).

the P heads are nice because they have no emissions passages in them (although i could have that backwards with other gt40 heads)

when you talk about heart-shaped combustion chamber, you get into complicated topics like quench. as long as you dont' have domed pistons specifically designed for normal chambers you shoudl be fine, although you're gonna have to look into the compression you're gonna make here. i personally think those chambers would help you out a little.

most normal engines have only 1 angle in their valve seats, because they're not performance engines and dont' need more than that. average guys will put three angles in the seats (30, 46, and 61 degrees if memory serves) to improve heat dissipation from the valves themselves and improve flow. a 5 angle valve job is not going to substantially improve your performance numbers, it's more for people who are trying to pick up a few small fractions of a second. it improves flow a small amount. i believe it adds 2 angles to the numbers i specified before, 1 smaller and 1 steeper.

hope that helps

[eillob]

I dont think thats a bad deal, it were me though for $700. bucks I think I would spend another $300 to $375 and go with an aluminum edelbrock head or twisted wedge and not only benefit from better flow but also gain from better weight reduction from a lighter head. Just my

[StangNut86]

Originally Posted by eillob

I dont think thats a bad deal, it were me though for $700. bucks I think I would spend another $300 to $375 and go with an aluminum edelbrock head or twisted wedge and not only benefit from better flow but also gain from better weight reduction from a lighter head. Just my

i totally agree, a set of trick flow twisted wedge type r heads go for something like 8 or 9 hundred each, complete with valves and springs. i'd go for that (and probably will)

i've heard that using twisted wedge heads can have a big effect on pushrod wear, but not if you use good pushrod guides. is this true?

[1Quick91]

Originally Posted by StangNut86

first, what kind of motor and what displacement will these heads go on?

the larger intake and exhaust valves will help you, but only if you have a came that's suited to these heads and your application (turbo, blower, nos, etc).

the P heads are nice because they have no emissions passages in them (although i could have that backwards with other gt40 heads)

when you talk about heart-shaped combustion chamber, you get into complicated topics like quench. as long as you dont' have domed pistons specifically designed for normal chambers you shoudl be fine, although you're gonna have to look into the compression you're gonna make here. i personally think those chambers would help you out a little.

most normal engines have only 1 angle in their valve seats, because they're not performance engines and dont' need more than that. average guys will put three angles in the seats (30, 46, and 61 degrees if memory serves) to improve heat dissipation from the valves themselves and improve flow. a 5 angle valve job is not going to substantially improve your performance numbers, it's more for people who are trying to pick up a few small fractions of a second. it improves flow a small amount. i believe it adds 2 angles to the numbers i specified before, 1 smaller and 1 steeper.

hope that helps

Sorry I thought the board already knew what my specs were. Here they are listed...

My Mustang Mods are Coast High Performance 347 short block, new Anderson Motorsports N41 cam, Professional Products Typhoon Manifold ported and polished by Anderson Ford Motorsports and GT 40 heads, 1.7 rockers, 77mm Mass Air, 70 mm Throttle body, 30 pound injectors, a new 9 PSI ATI Pro charger with intercooler, Mac Shorty Headers, Flowmasters, Art Carr Street/Strip AOD transmission, 3:73 gears, 3000 stall convertor ...18inch Cobra R Rims and Nitto Drag tires, 5 Lug conversion and 4 wheel disk brakes.

My car already runs 11 seconds, I am just looking for a little more breathing... I would like to increase my boost to 14 PSI and I will need better flowing heads than the stock GT40's...I have... Also would not mind saving a buck...

I figure I could sell my old heads on ebay for $300-400...

[1Quick91]

Originally Posted by StangNut86

i totally agree, a set of trick flow twisted wedge type r heads go for something like 8 or 9 hundred each, complete with valves and springs. i'd go for that (and probably will)

i've heard that using twisted wedge heads can have a big effect on pushrod wear, but not if you use good pushrod guides. is this true?

I thought of the trick flow heads, except they are stud mount rockers, I have pedastal mount also the heads take 1/2 inch bolts instead of 7/16 to bolt to the block. I would have to retap the block for 1/2in studs or use the ARP 7/16 head bolt with 1/2 in sleeves... This is not very strong... also the heads are not ported or polished...

So the extra $300 turns into like an extra $1200 with the purchase of bolts, machining, rockers etc...

The only reason I was thinking of adding the GT40P heads was for the better flow at an inexpensive price...

I am mostly looking for anyone who has run these heads at the track and what type of performance are they getting.

[GTStang]

With your set-up your throwing more money into shit that isn't cutting it with what you have. A blown 347 you should be looking at AFR's 185's or worked over TFS high ports. I wouldn't even waste my money on those heads cause they would still be the a weak link in your chain just like the one's you already have on there.

[1Quick91]

Originally Posted by GTStang

With your set-up your throwing more money into shit that isn't cutting it with what you have. A blown 347 you should be looking at AFR's 185's or worked over TFS high ports. I wouldn't even waste my money on those heads cause they would still be the a weak link in your chain just like the one's you already have on there.

So you are saying a set of AFR 185, I researched the AFR 185 Heads They have 2.025 intake and the same 1.60 exhaust valve. They also have 61cc combustion chambers compared to the Ported GT40P with 58cc combustion chamber. The AFR 185 flow 236cfm @28" of H20 the GT40P will Flow 221cfm @ 28" of H20. Also both heads have a .550 spring lift. Ported and polished the GT40p heads should flow around 255 cfm or so I am told by the shop selling these heads. Not sure what the AFRs' will flow ported and polished. If I stick with the GT40P heads my compression ratio will remain at 9.5 if I go the AFR route it is going to increase to about 10.5 to 1. I am concerned how this will effect my supercharger.

Will be making a new head purchase in the very near future because I relize my setup needs to breath better it is just trying to decide which heads to go with...

[StangNut86]

i'd say base compression should be your biggest concern here. i might even go as far as to suggest having whatever heads you buy milled out, and getting lower-compression pistons as well. remember, it's not boost that makes power, it's volumetric efficiency.

i think the trick flow heads will end up costing you less. just because of the lower base price. i think they have bigger comb. chambers too.

when i go FI on my windsor, i'm going to change pistons to get a ratio of 7.0:1. big power =D

[GTStang]

How will going to heads with a 61CC combustion chamber going to raise your compression to 10.5:1 if the same engine with 58CC combustion chamber heads is 9.5:1?

Next you can buy AFR 185's in 58CC or 61CC Combustion chamber set-ups. And your flow numbers are for at what lift?

http://www.airflowresearch.com/ Take a look and get informed

[Matts50]

Originally Posted by 1Quick91

Coast High Performance 347 short block, new Anderson Motorsports N41 cam, Professional Products Typhoon Manifold ported and polished by Anderson Ford Motorsports and GT 40 heads, 1.7 rockers, 77mm Mass Air, 70 mm Throttle body, 30 pound injectors, a new 9 PSI ATI Pro charger with intercooler, Mac Shorty Headers, Flowmasters, Art Carr Street/Strip AOD transmission, 3:73 gears, 3000 stall convertor ...18inch Cobra R Rims and Nitto Drag tires, 5 Lug conversion and 4 wheel disk brakes.

My car already runs 11 seconds, I am just looking for a little more breathing... I would like to increase my boost to 14 PSI and I will need better flowing heads than the stock GT40's...I have... Also would not mind saving a buck

A blown 347 ONLY running 11's? Why does that sound so slow to me? I'm pretty sure I've seen N/A 347's in the 10's.


Matt

[boosted331]

Originally Posted by Matts50

A blown 347 ONLY running 11's? Why does that sound so slow to me? I'm pretty sure I've seen N/A 347's in the 10's.


Matt

I'm also 110% sure earlier on here he said he had a zex kit on his car and his car has gone low 10's Not to mention the 18" nitto drag radials arn't even out yet I'd take this post with a grain of salt.....

Keep in mind this is the dude that said "the gt40 heads are far from crap as they have been professionally ported and flow better than windsor jr's. If you new anything about 5.0 stangs you would know the gt40 is one of the best heads for this engine..." GT40P's: 237CFM AFR 185's: 277 CFM.

GT40P's: 237CFM AFR 185's: 277 CFM. Yes, GT40's are one of the best heads for 5.0's This assbag also posted that he spins his STOCK BLOCk 347 with a hydraulic E-cam to 6700 RPM's, and that he has gone 10.729 @ 125.89 with his unrelased 18" nitto drag radials cutting a 1.56 60 foot. Give it up buddy, you arn't fooling ANYONE.

[1Quick91]

Originally Posted by boosted331

I'm also 110% sure earlier on here he said he had a zex kit on his car and his car has gone low 10's Not to mention the 18" nitto drag radials arn't even out yet I'd take this post with a grain of salt.....

Keep in mind this is the dude that said "the gt40 heads are far from crap as they have been professionally ported and flow better than windsor jr's. If you new anything about 5.0 stangs you would know the gt40 is one of the best heads for this engine..." GT40P's: 237CFM AFR 185's: 277 CFM.

GT40P's: 237CFM AFR 185's: 277 CFM. Yes, GT40's are one of the best heads for 5.0's This assbag also posted that he spins his STOCK BLOCk 347 with a hydraulic E-cam to 6700 RPM's, and that he has gone 10.729 @ 125.89 with his unrelased 18" nitto drag radials cutting a 1.56 60 foot. Give it up buddy, you arn't fooling ANYONE.

Man, you are a complete idiot... I do not know where you get off calling me a liar. I have run 10.729 with the Zex kit and I run 11's without the gas. I am no longer running the Zex kit because it was just to much. The last time at the track I blew my head gasket when I was running the Juice. So when I replaced my head gasket I removed the Zex Kit from my car. I am also running Nitto Drag Radials and I have been for about 4 months now. The Model of tire is Nitto NT 555 R and the tire size is 285/35 ZR18. These tires can be ordered from any reputable tire dealer. I am also running a complete Hotchkis Drag suspension kit with Eibach Drag Springs. My rear is an 8.8 inch ford with an Eaton Posi-Traction Differential and 31 spline axles with C clip eliminators. So I have no problems with launches. I also have a QA1 Tubular K member with QA1 Front control arms.

So butt-much you can remove your foot from your mouth now.

I have also posted my time slip on this board for all to see. What do you think they sell those time slips at the track for souveniers, No you only get them when you complete a run.

Not my fault you have a slow car and are jelous of my Stang... My car is a sleeper and I like it that way. This way assholes like you will get smoked on a regular basis.

Yes GT40's are some of the best heads for 5.0 Fords. The Gt 40P's are much better and flow alot more. A good set of ported and polished GT40p heads with 1.90 intake and 1.60 exhaust with a .550 spring kit at 120lbs will flow 255 cfm or so I am told by the Shop building this head. I am considering these heads over my GT40's because of the higher flow rate and larger intake and exhaust valves. Also I am not spending 1500.00 for a set of aftermarket heads. These GT40p heads are half the price.

I am also not running an E-cam any longer. I just changed it out for the Anderson Motorsport N41 cam which is a blower cam.

So next time you want to butt in on things you have no idea about, do us all a favor and DON'T...

What an Ass!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[1Quick91]

Originally Posted by Matts50

A blown 347 ONLY running 11's? Why does that sound so slow to me? I'm pretty sure I've seen N/A 347's in the 10's.


Matt

Getting into the 10 second zone is really hard, I have only done it once and that was with Nitrous... I also ended up blowing my head gasket when I was trying to back up the 10 second time with another run...

[SIKCRX]

Originally Posted by 1Quick91

Man, you are a complete idiot... I do not know where you get off calling me a liar. I have run 10.729 with the Zex kit and I run 11's without the gas. I am no longer running the Zex kit because it was just to much. The last time at the track I blew my head gasket when I was running the Juice. So when I replaced my head gasket I removed the Zex Kit from my car. I am also running Nitto Drag Radials and I have been for about 4 months now. The Model of tire is Nitto NT 555 R and the tire size is 285/35 ZR18. These are special order tires and can be ordered from any reputable dealer. I am also running a complete Hotchkis Drag suspension kit with Eibach Drag Springs. My rear is an 8.8 inch ford with an Eaton Posi-Traction Differential and 31 spline axles with C clip eliminators. So I have no problems with launches. I also have a QA1 Tubular K member with QA1 Front control arms.

So butt-much you can remove your foot from your mouth now.

I have also posted my time slip on this board for all to see. What do you think they sell those time slips at the track for souveniers, No you only get them when you complete a run.

Not my fault you have a slow car and are jelous of my Stang... My car is a sleeper and I like it that way. This way assholes like you will get smoked on a regular basis.

Yes GT40's are some of the best heads for 5.0 Fords. The Gt 40P's are much better and flow alot more. A good set of ported and polished GT40p heads with 1.90 intake and 1.60 exhaust with a .550 spring kit at 120lbs will flow 255 cfm or so I am told by the Shop building this head. I am considering these heads over my GT40's because of the higher flow rate and larger intake and exhaust valves. Also I am not spending 1500.00 for a set of aftermarket heads. These GT40p heads are half the price.

I am also not running an E-cam any longer. I just changed it out for the Anderson Motorsport N41 cam which is a blower cam.

So next time you want to but in on things you have no idea about, do us all a favor and DON'T...

What an Ass!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

OWNED!!!