if you get the A/F in the low 11's where it should be (ie tuning via piggyback) - you would easily see 375HP... the reflash is really the only thing holding me back - if the "tuner" version is somewhat cheaper, I might consider it, but until then I think I'm holding off...

 

That dyno chart is interesting. It does look like you might ne running about a 1/2-1 PSI lower then you should. Have you verified theres no boost leaks anywhere? What does your boost gauge read. The power numbers seem about right for that amount of boost and AFR. Taurran is right however. Typically a N/A header can show lower power numbers when used with boost. This is mainly due to the size of the runners. Typically with bigger runners the velocity of the exhaust gas is reduced...

 

Does it appear to anyone else that there might be a very small boost leak in play here? The A/F is a little rich and the boost is low. I think most people are pulling between 8.5 and 9 PSI of boost (I'm a little over 10 PSI). If there were a leak and it were fixed, it would increase manifold pressure and raise the A/F ratio. It would also increase your power a bit. What octane gas do you have up there in NY? If you get 93, I believe you should be closer to 370, but I'm no expert. In any case, the kit sure is just fun as hell, isn't it?

EDIT: Just saw your post above MIA....Guess we're thinking down the same road.

 

Can you point me out how to check for a boost leak? I'm running 93 octane here. TIA.


PAtrick

 

Well a couple things to look at. First ensure the boost sginal line goes to the upper Blow off valve port. Second check all the silicone couplers along the intake tract and ensure there no cuts or tears anywhere.

 

Well, for a boost leak to be affecting A/F, it would have to be post-MAF, so check all of the pipes/fitting/T-bolt clamps from the MAF to the plenum to make sure that you have good seats. I think someone said to spray carb cleaner around the plenum seat and listen for idle RPM changes. If the RPM changes, then the carb cleaner is getting sucked under vaccuum into the intake through the leak.

Anyone more mechanically inclined want to add?

 

Ok Guys! Just dropped off my car to switch out the Stillen headers and put the stockers back on. Also bought some heat wraps to wrap up all the pipes. Also Ask the guys to check out some vibration too, like when you shift gear...there is a vibration. Also when you let off the gas and clutch while in motion and in gear, and the car slow down which create a vibration that It's really bothers me.

Dyno? heheheh...it's gonna be another $55 for 3 pulls. If each of you chip in like $10 each then Will dyno it this week and post the result :LOL:

PS: Also put in 1 step colder plugs in yesterday. it was fun putting them in Car runs the same as before.

 

Sounds good. I'm VERY interested in seeing some side by side comparisons with/without the headers. I'm taking my stock manifolds in tomorrow for some high temp coating, and I'm going to be swapping out the headers as soon as I can get the car in the shop. I just wish I had a garage of my own to do it.

I'm not sure what might be causing a vibration. Does it sound like it's coming from down around the driver's side foot well? If so, then it might be your downpipe. Also make sure that the pipe isn't contacting the body further down. Mine was rattling a bit and making noise when I first had the kit installed so we put it on a lift and beat the body back a little to give it some clearance.

 

I have this same vibration, but it existed before the S/T kit went in.....sometimes when I am decelerating in gear, I get a vibration that is very strong, felt primarily through the shift lever, but can also feel it in the seat. I never thought much of it, but I guess I should.

 

I feel you on the vibrations, strange too... Sounds like it is coming from the front... And it doesn't happen all the time either.

 

I get this vibration once in awhile as well...and my car is still N/A. More of a "z" thing than a turbo thing. Has something to do with the car decelerating with the transmission.

 

I never heard it before the boost, I think it may be something like the oil line hitting something on the fans plastic backing... But I don't really know since I can't be under the hood when the car is slowing down

 

Yeah, I don't know what to tell you...it's almost like the flywheel or clutch doesn't like to decelerate from high RPM's when in gear....And you feel it mostly thru the shifter. Try winding out 4th gear and letting off the gas....(yeah, I know, you'll be at 120mph++...but try it!)

 

Yeah, much different than my old high revving Honda

 

Exactly!!! That's where I feel it too....It's comforting to know that I'm not the only one who gets this...maybe that means it's normal?

 

My car has always done what you descirbe. From the day it left the lot...

 

I am not sure exactly how the ECU is reflashed but I believe it is rpm x load.The ECU cannot comprehend boost. So if he is making boost later in the rpms then it could be that the ECU is just flashed that way for a particular rpm.This means that the tuning will be off in that range.The fuel pressure is not a boost dependant rising rate system so this will have little impact if he is not making the correct amount of boost.


As far as boost leak goes....if the above case scenario is true then his boost leak could be on the exhaust side.This can be verifed with an air hose and some soapy water.

 

Guys! Just finished swapping out the Stillen headers and put the stocks back on. Can't tell a different in power. But one good thing is that the vibration that I described before is now gone. Yes! No more vibration when de-celarating when in gear. Before i drop the car off, I asked my installer to check out the vibration. He said it might be the bracket on the down pipe is not tighten enough or is not doing its job. He tighten the bracket and keep it tight and now the vibration is gone. I test drove it today and tried to manipulate the situation and there was no vibration. It's so relaxing now. Will dyno the car with the stockies and post the dyno graph side by side with the Stillen headers.

 

Sounds good. I'm not sure if you would be able to feel any power gains from the manifolds, as it would be under 10hp if anything. Can you tell a difference in how soon you're hitting boost?

Once again, I look forward to seeing your dyno comparison.

 

This kit sounds interesting too!
anybody got some numbers 0-60, 60-125 or 0-125 mph?
and how to handle the kats with this kit, would the greddy evo II exhaust also work?


thanks a lot