Sounds like choke flow to me somewhere in the exhaust. The o2 would be my first bet.

What dyno brand?

I assume you're saying 23 lbs flat across the board? As well as 20 both equate to 397?

People typically quote peak boost which is not coincidental with peak hp. Close to torque though

 

Hey there -- thanks for the reply 211ratsbud. The dyno is a Mustang Dyno. I went to PURE tuning in Toledo. I've been thinking about this ALL NIGHT. He, the tuner, suggested a choking point somewhere. I've been thinking about my exhaust (HKS Hi Power Cat Back with Megan Racing Downpipe -- nothing restrictive there), the cams GSC S2 -- I can't see how those would be it?? I was told by GSC that is there latest grind, the 02 housing sure since it's stock and my intake is a AEM.

No matter what we did with the boost nothing would change on the top end. At 20 lbs we did see a little taper by the end. At 23 we saw an improvement below at 5,500 (again we had taper) but nothing up top. I'm really baffled. This build should be producing WAY MORE power than that.


It was suggested I look into Kelford 272's, Nvidia o2 housing and I'm still waiting for CBRD to get back to me about their intake for this turbo (i have the anti-surge cover so that makes the inlet 3.5" in diameter). I'm just scratching my head here..

Below is my dyno sheet... ideas????

 

Your numbers seem fairly close to me. How many lb min?

Edit search came up with 57 lb min.

I firmly believe the cams are not it.

What kind of power are you anticipating?

 

This almost the most ridiculous thread I have ever seen. People are asking about cams yet they don't even have a basic understanding of how they work. Cams affect engine efficiency so if a car makes a little more or less power at the same boost is what bigger of smaller cams will affect. However cams will not restrict you to a certain power level. Many people have made 700 plus HP on S2 cams. The single most important thing is to degree the cams. If you don't do that then you are short changing yourself. If you understand what changing the overlap does and you are on a Dyno you can try to modify the powerband to your liking. If you are limited to a certain power level well below normal there is something mechanical restricting flow. To go changing cams is your tuner juicing you for labor and parts money.

 

Are you sure that you have cam timing correct? With the taller 2.4 block, its pretty easy to get the cams one tooth off.

On my 2.4 block IX I made >600 on an fpblack and set of S2 cams. ( after I got the cam timing correct )

John-

 

I was told that this build should put me mid 400's. I'm thinking the same thing with the cams. I'd believe it's the intake or 02 housing before the cams. I haven't seen ANYONE post that the cams are the problem on their build. But I will still be contacting GSC today.

 

The engine was not built by me. The cams were degreed in by the builder. If I look at the cam gears the settings are dead on every other picture I've seen on here. I can take a picture if you'd like to see it.

As I mentioned above I'm hesitant to believe it's the cams. That's why I'll be contacting GSC for assistance.

 

your issue is not the s2 cams. probably better off starting a new thread.

 

you need to get the exhaust opened up and see what happens. The S2 cams can move a lot of air, much more than the stock O2 housing can support. If everything else in the graph looks that good, there is no issue with the cams or cam timing. Also what valve springs do you have? didnt see it in the previous posts.

 

The GSC S2s just need a fine tuning to get the car running perfectly.

 

Stock O2 housing doesnt flow past 400whp. I am kind of amazed that you think it could be anything else. It is shaped like this - ?

Making more than a 90* turn with occluded flow doesnt make for much power. Since it cant flow, it gets hot, when it gets hot the propensity for knock is higher and that is a killer on gas. You didnt say what fuel you were using but I am presuming for how low the boost is you arent on E85?

 

I've never seen a stock o2 housing but for 100$ you can get a Megan one, I think that's the best bang for the buck until you step to a one piece o2/dp combo.

 

i have newer style s2's and love them, numbers are in my sig stock bottom end over 110k miles and pump gas, definatley is not the cams, tuner or the o2 housing, i personally run a buschur one