Cylinder head work
Originally Posted by Ted B
I haven't seen any EVO that can demonstrate anywhere near a 60hp gain at that power level through head porting and TB porting (which by the way, hasn't shown much of anything at all). Actually, I haven't seen anything from head porting in this application that impresses me enough to even consider it, although I have seen stock heads deliver well over 500whp.
Based on my results if you are running a stockish turbo you will not notice a significant gain other than some in high end. My porting was done by a really reputable and experienced shop - they did a great job - problem is that w/ stockish turbo the head is flowing more than the turbo can support. The turbo is teh slowest part of the river so to speak. I got what most would consider a street port (ie - I did not go 1mm over).
That said, I do believe that you will see gains with a larger turbo. Depends on your application. In hindsight I would have probably done this mod last if I had to do it over again. I could have purchased a nice turbo kit for what I spent on my head. This mod is when you're looking for that last 10/10ths.
Last edited by 954DRGSR; Jun 28, 2005 at 04:57 PM.
Originally Posted by 954DRGSR
I agree on some points. I am running a ported head, larger throttle body and ported intake manifold. Running 272's all around, full ferrea valvetrain & 10.5 hotside etc etc.
Based on my results if you are running a stockish turbo you will not notice a significant gain other than some in high end. My porting was done by a really reputable and experienced shop - they did a great job - problem is that w/ stockish turbo the flowing more than the turbo can support. I got what most would consider a street port (ie - I did not go 1mm over).
That said, I do believe that you will see gains with a larger turbo. Depends on your application. In hindsight I would have probably done this mod last if I had to do it over again. I could have purchased a nice turbo kit for what I spent on my head. This mod is when you're looking for that last 10/10ths.
Based on my results if you are running a stockish turbo you will not notice a significant gain other than some in high end. My porting was done by a really reputable and experienced shop - they did a great job - problem is that w/ stockish turbo the flowing more than the turbo can support. I got what most would consider a street port (ie - I did not go 1mm over).
That said, I do believe that you will see gains with a larger turbo. Depends on your application. In hindsight I would have probably done this mod last if I had to do it over again. I could have purchased a nice turbo kit for what I spent on my head. This mod is when you're looking for that last 10/10ths.
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Yes, I believe that it depends on the application. But I still haven't driven the car yet since the head's only being installed today. Its done and started up etc and I will baby the car for 500 miles before another oil change then i will run it hard and go on a dyno.
Before this cylinder head package, I was only running a 3" downpipe, high flow cat (3" in/out) and an espelir exhaust. Although I doubt that I feel a little difference specially since i'm going from stock cams to a 274/274 setup, it has still yet to be seen. I know that this is a big difference from STOCK.
I'm going to be optimistic on this setup until I've actually driven the car and find out for myself what the difference is..
Don't knock it til you try it
Before this cylinder head package, I was only running a 3" downpipe, high flow cat (3" in/out) and an espelir exhaust. Although I doubt that I feel a little difference specially since i'm going from stock cams to a 274/274 setup, it has still yet to be seen. I know that this is a big difference from STOCK.
I'm going to be optimistic on this setup until I've actually driven the car and find out for myself what the difference is..
Don't knock it til you try it
Originally Posted by emperor_gp
Yes, I believe that it depends on the application. But I still haven't driven the car yet since the head's only being installed today. Its done and started up etc and I will baby the car for 500 miles before another oil change then i will run it hard and go on a dyno.
Before this cylinder head package, I was only running a 3" downpipe, high flow cat (3" in/out) and an espelir exhaust. Although I doubt that I feel a little difference specially since i'm going from stock cams to a 274/274 setup, it has still yet to be seen. I know that this is a big difference from STOCK.
I'm going to be optimistic on this setup until I've actually driven the car and find out for myself what the difference is..
Don't knock it til you try it
Before this cylinder head package, I was only running a 3" downpipe, high flow cat (3" in/out) and an espelir exhaust. Although I doubt that I feel a little difference specially since i'm going from stock cams to a 274/274 setup, it has still yet to be seen. I know that this is a big difference from STOCK.
I'm going to be optimistic on this setup until I've actually driven the car and find out for myself what the difference is..
Don't knock it til you try it
1. Did they take any pictures of the head?
2. Did they flow it before and after?
3. Why are you babying the car for 500 miles? Clutch?
Also my comments were not meant to dissuade you from this path, merely to indicate my experience. Also on my car the only change before and after installing the head was additional tuning - I had the cams throttle body & intake mani installed and tuned beforehand. (I had purchased another head to send out)
Last edited by 954DRGSR; Jun 28, 2005 at 07:15 PM.
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Originally Posted by mikiblueeyes
so did you at least gain 10HP with ported head?
What would you think White Rabit or 3071 rinning 25PSI would gain on Ported head vs Stock?
What would you think White Rabit or 3071 rinning 25PSI would gain on Ported head vs Stock?
All I can say is OH MY GOD! The EVO pulls hard! As soon as boost kicks in (around 2800 rpm), it just goes and pulls! The 274/274 combo wasn't as bad as I thought. Idle was just a bit different but that's all. It was hard to baby it as the engine just wants to give you more and more! It was incredible!
It took all but 10 mins of driving around to get used to the clutch. Pedal feel is just a little heavier than stock and it engages just about where the stock clutch did. Just rode it briefly and let it out. Perfect.
I'M TOTALLY HAPPY!
I'd have to say that I gained a LOT of HP from having a stock engine to now. Last night's driving experience was just UNBELIEVABLE. Considering that I was shifting at or below 5000 rpm, the engine just keeps on rewarding me with all this power. I really don't know what else to say.
After the 500 mile grace period (I am doing this to ensure the head gasket seals COMPLETELY before I do any hard runs), the oil's going to get changed then on the dyno I go. I will be posting those results as soon as it it done.
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The head job consisted of:
Ported and polished cylinder head
Racing valve grind
Ported throttle body (69 mm)
Ported intake manifold
Reground cams 274/274
Price was $1750
These guys did a great job on my head and with the cams included, is the best bang for the buck IMO.
Ported and polished cylinder head
Racing valve grind
Ported throttle body (69 mm)
Ported intake manifold
Reground cams 274/274
Price was $1750
These guys did a great job on my head and with the cams included, is the best bang for the buck IMO.