Which heads for 500+bhp
#1
Which heads for 500+bhp
Hi,
Doing a few bits to my classic at present and thinking whilst I've got a few bit of it to rip the engine out and go for the 500bhp car I've always wanted.
Its currently running a Cosworth EJ 257 short block but running the standard uk turbo 2.0l heads.
Last had it mapped and dynoed at power station and Fuzz said it was the heads that are holding it all back to the current 400ish bhp..
Id love a set of cosworth heads but just cant fork out 6k for two heads plus all the gaskets on top..
Anyone else produce any decent heads that are more affordable?
Doing a few bits to my classic at present and thinking whilst I've got a few bit of it to rip the engine out and go for the 500bhp car I've always wanted.
Its currently running a Cosworth EJ 257 short block but running the standard uk turbo 2.0l heads.
Last had it mapped and dynoed at power station and Fuzz said it was the heads that are holding it all back to the current 400ish bhp..
Id love a set of cosworth heads but just cant fork out 6k for two heads plus all the gaskets on top..
Anyone else produce any decent heads that are more affordable?
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v5 ported to within an inch of their life. you might also benefit from a cam and valve change. of course to pull it altogether you will need adjustable pullys. not a cheap option depending on how much time someone spends porting the heads.
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#6
Just want to get to the 500bhp mark without pushing everything to the limit..Not running methanol as thats cheating
Ill gladly go way over that if things will take it, should do
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Hard to tell when you dont state what Turbo your running, i would say there is no need to go to the expense of V5 ported heads.
Folk have got results on standard heads, if your running syvecs then the answer is newage heads.
Depending on the year factor in inlet manifold changes and any wiring that may be required to use AVCS heads.
Folk have got results on standard heads, if your running syvecs then the answer is newage heads.
Depending on the year factor in inlet manifold changes and any wiring that may be required to use AVCS heads.
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Hi,
Doing a few bits to my classic at present and thinking whilst I've got a few bit of it to rip the engine out and go for the 500bhp car I've always wanted.
Its currently running a Cosworth EJ 257 short block but running the standard uk turbo 2.0l heads.
Last had it mapped and dynoed at power station and Fuzz said it was the heads that are holding it all back to the current 400ish bhp..
Id love a set of cosworth heads but just cant fork out 6k for two heads plus all the gaskets on top..
Anyone else produce any decent heads that are more affordable?
Doing a few bits to my classic at present and thinking whilst I've got a few bit of it to rip the engine out and go for the 500bhp car I've always wanted.
Its currently running a Cosworth EJ 257 short block but running the standard uk turbo 2.0l heads.
Last had it mapped and dynoed at power station and Fuzz said it was the heads that are holding it all back to the current 400ish bhp..
Id love a set of cosworth heads but just cant fork out 6k for two heads plus all the gaskets on top..
Anyone else produce any decent heads that are more affordable?
I wouldn't say that heads alone are holding your engine back to 400 bhp, as we've seen much more than that from stock heads on 2.5's. It's more about the characteristics from these, which are about a whole load of torque, with the graph dropping off just as you're beginning to enjoy yourself.
The Cosworth heads aren't any good for your car anyway being designed for US spec AVCS.
Assuming your heads are in good order, we can flow them and fit large stainless/inconel valves good enough to match the Cosworth spec from around £1500 upwards, depending on choice of retainers etc. A set of cams at £700 will add a whole stack of flow just at the point where your current set up is taking a dive.
They'll look something like this: (AVCS heads shown)
#11
Hi,
Ok maybe im being stupid as new to imprezas but whats AVCS?
The problem i currently have with mine is this:
When the car was built years back the old owner (fuzz from powerstation) ported the exhaust ports and the new headers he purchased for the car..
Ive just got hold of some RCM headers but as you can see in the pics below the holes are much smaller then the old headers ports so wll create a big lip when bolted up the heads..
So im tempted to just grind the new header ports or go all out and just get some nice new heads and go for the 500bhp..
This was my graph but i had been running it on BP Ultimate so was knocking badly so fuzz had back things off hence the 400/400..Was 440 before at the same 1.5bar
Will i have to send my headers to get ported also if i go for your heads?
Cheers
Gavin
Ok maybe im being stupid as new to imprezas but whats AVCS?
The problem i currently have with mine is this:
When the car was built years back the old owner (fuzz from powerstation) ported the exhaust ports and the new headers he purchased for the car..
Ive just got hold of some RCM headers but as you can see in the pics below the holes are much smaller then the old headers ports so wll create a big lip when bolted up the heads..
So im tempted to just grind the new header ports or go all out and just get some nice new heads and go for the 500bhp..
This was my graph but i had been running it on BP Ultimate so was knocking badly so fuzz had back things off hence the 400/400..Was 440 before at the same 1.5bar
Will i have to send my headers to get ported also if i go for your heads?
Cheers
Gavin
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Hi,
Ok maybe im being stupid as new to imprezas but whats AVCS?
The problem i currently have with mine is this:
When the car was built years back the old owner (fuzz from powerstation) ported the exhaust ports and the new headers he purchased for the car..
Ive just got hold of some RCM headers but as you can see in the pics below the holes are much smaller then the old headers ports so wll create a big lip when bolted up the heads..
So im tempted to just grind the new header ports or go all out and just get some nice new heads and go for the 500bhp..
This was my graph but i had been running it on BP Ultimate so was knocking badly so fuzz had back things off hence the 400/400..Was 440 before at the same 1.5bar
Will i have to send my headers to get ported also if i go for your heads?
Cheers
Gavin
Ok maybe im being stupid as new to imprezas but whats AVCS?
The problem i currently have with mine is this:
When the car was built years back the old owner (fuzz from powerstation) ported the exhaust ports and the new headers he purchased for the car..
Ive just got hold of some RCM headers but as you can see in the pics below the holes are much smaller then the old headers ports so wll create a big lip when bolted up the heads..
So im tempted to just grind the new header ports or go all out and just get some nice new heads and go for the 500bhp..
This was my graph but i had been running it on BP Ultimate so was knocking badly so fuzz had back things off hence the 400/400..Was 440 before at the same 1.5bar
Will i have to send my headers to get ported also if i go for your heads?
Cheers
Gavin
#13
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AVCS is the variable camshaft timing set up used on the inlet cams for STI newage.
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