Help...Quest for 700 RWHP...Need 80 more..How To...

[00prowler]

Need opinions on this one. I have a 96 GTS, Roe S/C 10# pulley, **** injection, tubes & filters, Roe hi flow cats, Corsa exhaust..I just had it dynoed on a Dynojet @ 620 RWHP.. I want to use bolt ons, rather than internals like heads and cam. I guess headers and 1.7 rockers are in order, but I dont think that will get me there. Will a special airbox be worth it? What other items am I not thinking of? Is there anyone hear making 700 RWHP with a similar setup? Thanks...00PROWLER...P.S. no nitrous...

 

[Anaconda]

How about a Vec2, headers, and the rockers?

 

[00prowler]

Anaconda, The Roe S/C comes with a VEC 2...00PROWLER...

 

[99 R/T 10]

You don't have a Vec 2?

 

[Shelby3]

I think you're kind of painting yourself in a corner here. An airbox ain't gonna do much of anything. Headers and rockers will help but not likely that much. Tiny very safe shot of juice and you're more than there. Do not resist the juice.

 

[Anaconda]

Anaconda, The Roe S/C comes with a VEC 2...00PROWLER...

Oh, whoops. I didn't know that (obviously).

 

[STUGOTS]

did you have it dyno tuned? like Vos or somewhere??

Headers and rockers together will do 50 - 60 at the most.

Maybe go to a 12 Psi pully?

 

[00prowler]

Stu, I had it dynoed locally and sent the graphs to Sean Roe for tweaking. I have been having a huge problem with pinging on my particular car. I am finally rid of it. Sean gave me a larger **** injector for one side which seemed to work, as well as bringing the **** on sooner...00PROWLER...

 

[plumcrazy]

spray it

 

[IEATVETS]

You will easily get there with a shot of nitrous.

 

[Russ M]

Headers/Rockers/no cats

An airbox while not beneficial on an NA car may give you a considerable boost with a super charger. The only way to know is test before and after on a dyno.

I would also think that you are at the limit of the factory fuel pump. Have you asked Sean Roe if you can make any more power with your current fuel system?

 

[JUCD VPR]

open up the heads LOL along with those other little bolt ons.

 

[onerareviper]

What did Sean say? At 10 lbs. with the ****. inj. + add headers/catless/1.7 rr I would imagine you could reach the 700 RWHP mark. It seems with the forced induction it is all in the tune. And being Larry at M2 seems to be the wizard with the Roe units, you need to make a phone call.....

 

[davem]

Hello,
Rockers will get you 20hp (I've done a back to back before/after dyno test to prove this). Make sure you drive the car fairly hard for a few hundred miles and re-adjust them. Headers, and no cats should buy you another 20hp on top of this.

I think your tune may be conservative, similarly prepared cars to yours that we have done are making closer to 670whp, this is on 93 octane, and relatively cool weather (60-70 degrees) at sea level, corrected.

So first thing I would do is to try to find out where your knock is coming from, get rid of it, and add some more timing back in, this should be good for another 20-40 hp. Where are you running the crankcase vent hose? If your running this back into the intake this is likely the cause of your knock, dump it to a catch can. You could have carbon in the cylinders that are creating hot spots that are creating the knock too, maybe try some sort of cylinder decarboning spray? I'm sure your running colder plugs already.

All of the above, some 104 octane and a new vec 2 tune to take advantage of the better knock threshould should get you there without opening the motor....

good luck,
Dave.

 

[00prowler]

What did Sean say? At 10 lbs. with the ****. inj. + add headers/catless/1.7 rr I would imagine you could reach the 700 RWHP mark. It seems with the forced induction it is all in the tune. And being Larry at M2 seems to be the wizard with the Roe units, you need to make a phone call.....

He is in Florida isnt he? Wouldn't it be hard for him to dial it in without having the car?...Thanks...00PROWLER...

 

[00prowler]

Hello,
Rockers will get you 20hp (I've done a back to back before/after dyno test to prove this). Make sure you drive the car fairly hard for a few hundred miles and re-adjust them. Headers, and no cats should buy you another 20hp on top of this.

I think your tune may be conservative, similarly prepared cars to yours that we have done are making closer to 670whp, this is on 93 octane, and relatively cool weather (60-70 degrees) at sea level, corrected.

So first thing I would do is to try to find out where your knock is coming from, get rid of it, and add some more timing back in, this should be good for another 20-40 hp. Where are you running the crankcase vent hose? If your running this back into the intake this is likely the cause of your knock, dump it to a catch can. You could have carbon in the cylinders that are creating hot spots that are creating the knock too, maybe try some sort of cylinder decarboning spray? I'm sure your running colder plugs already.

All of the above, some 104 octane and a new vec 2 tune to take advantage of the better knock threshould should get you there without opening the motor....

Dave, Does the catch can divert the hot vapors away from the intake charge? if so that sounds like a great idea...00PROWLER

 

[ChicagoGTS]

YIKES! I don't mean to rain on the parade here, but Prowler you need to be extremely careful here. You are already pushing the limit of your setup, and as Russ said your Fuel Pump. 650RWHP and you are walking a fine line on that build. It only takes a fraction of a second and one detonation to screw up an otherwise beautiful day (replace "day" with "engine") I'm not trying to be negative here, I'm just trying to say that if you cherish your car like the rest of us do on this board, bes safe, smart, but more importantly BE CAREFUL. Power adders are addictive.

Every 4-stroke engine goes through the same process "Intake, Compression, Combustion, Exhaust" and the same physics apply to every 4-stroke motor. Poor planning on any one of those processes can result in either serious damage and/or a $rebuild$. You are at what one would call a "bottle-neck". On top of that I don't think 96's have the same forged pistons either (not completely positive though).

As it stands you are not compensating for the "Exhaust" process in any way whatsoever. I use the term bottle-neck because your forcing more air, more fuel, and generating more heat during combustion and dispensing it through stock heads, stock valves, and a stock exhaust. The latter is probably the most alarming. The stock exhaust is VERY restrictive. I'm actually suprised you haven't blown the honeycomb's out of the cat's yet.

IMHO, the choice is simple and it kills 2 birds with one stone. Ventilate your engine it needs to breath go with Headers, Rockers, Catless, and an MSD Fuel Pump Booster. Your exhaust mods will be a little amplified thanks to the blower. That setup should put around where you want to be, but more importantly where your engine wants to be.

~Matt~

 

[GTSnake]

How about larger throttle bodies while you're at it?

 

[00prowler]

Chicago GTS, I have a MSD fuel pump booster on it now. Also 96 GTS has a forged piston motor....00PROWLER...

 

[aslowdodge]

from what i have seen here and on the alley, 700 hp probably needs heads. You can pulley up as much as you want, but the choke point is the heads, they simply cannot breath, so higher boost isn't getting you more hp. you will gain some torque, but little or no hp plus you may see your hp dropping off earlier as you pulley up and thus have lower shift points

 

[Sean Roe]

The HP graph will give an indication of how severe and where the "bottle-neck" is. If the HP starts rolling off in the upper RPM, most likely, it's an air flow issue.
As others have suggested, let the motor breath with headers (any 1&3/4" primary with 3" collector type will do), no cats, 1.7 rockers and bigger TB's. Usually, the stock TB's become a restriction (read, produce vacuum before the blower inlet due to restriction) when going over 585 RWHP.
The stock fuel pump with a voltage booster and WM injection can handle up to 700RWHP. With the mods mentioned, I'd say you'd be close to 680 RWHP and 710 RWTQ with a good tune. What is your RWTQ now?

Regards,
Sean

 

[99 R/T 10]

YIKES! I don't mean to rain on the parade here, but Prowler you need to be extremely careful here. You are already pushing the limit of your setup, and as Russ said your Fuel Pump. 650RWHP and you are walking a fine line on that build. It only takes a fraction of a second and one detonation to screw up an otherwise beautiful day (replace "day" with "engine") I'm not trying to be negative here, I'm just trying to say that if you cherish your car like the rest of us do on this board, bes safe, smart, but more importantly BE CAREFUL. Power adders are addictive.

Every 4-stroke engine goes through the same process "Intake, Compression, Combustion, Exhaust" and the same physics apply to every 4-stroke motor. Poor planning on any one of those processes can result in either serious damage and/or a $rebuild$. You are at what one would call a "bottle-neck". On top of that I don't think 96's have the same forged pistons either (not completely positive though).

As it stands you are not compensating for the "Exhaust" process in any way whatsoever. I use the term bottle-neck because your forcing more air, more fuel, and generating more heat during combustion and dispensing it through stock heads, stock valves, and a stock exhaust. The latter is probably the most alarming. The stock exhaust is VERY restrictive. I'm actually suprised you haven't blown the honeycomb's out of the cat's yet.

IMHO, the choice is simple and it kills 2 birds with one stone. Ventilate your engine it needs to breath go with Headers, Rockers, Catless, and an MSD Fuel Pump Booster. Your exhaust mods will be a little amplified thanks to the blower. That setup should put around where you want to be, but more importantly where your engine wants to be.

~Matt~

What he said, except that your car does have the forged pistons

 

[Paolo Castellano]

Need opinions on this one. I have a 96 GTS, Roe S/C 10# pulley, **** injection, tubes & filters, Roe hi flow cats, Corsa exhaust..I just had it dynoed on a Dynojet @ 620 RWHP.. I want to use bolt ons, rather than internals like heads and cam. I guess headers and 1.7 rockers are in order, but I dont think that will get me there. Will a special airbox be worth it? What other items am I not thinking of? Is there anyone hear making 700 RWHP with a similar setup? Thanks...00PROWLER...P.S. no nitrous...

Twin Turbo