My stock manifold data. >pics inside<

To compare my new exhaust manifold against any gains/losses with my new one, I made this. When I get the data finished on the new manifold, I will add that information to the graph. In the mean time let's look at what we achieved with it: (By we, I mean me, and my tuner Duster360, via email rescale)

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This was done on 91 octane. (I had a great deal of KR) I wanted to see how much boost I could push, and when the Drop Off was, so I could compare it to another manifold.

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wish i could understand this

It's easy man. The small ass turbo I have is a TD04LR. It flows poorly at high RPM's because it can't flow enough air. The air it does flow is also SUPER HOT. It's basically a blow drier.

It can boost a shit ton in lower rpms, But it has to be spinning at an ungodly rpm. It goes as fast as it can, and then at 3800 rpm's it can't keep up anymore.

The green line represents the trend in the ammount of air my turbo pushes, while the blue line represents my boost trend. See how low it is at 6K. Only 12.5psi. Thats depressing crap right there. And that's maxxed out on PCM control.

goodluck with the new manifold, hopefully you and the tuner can figure out a method on how to get that dropoff after 3800rpm fixed

Im may have some bad news. I can't boost as high with the SDK manifold, and still have the same dropoff. This may not be the case with a larger turbo, but IDK. As for the stock turbo I have verified my tune is correct, I have no boost leaks and the PCM has fully learned the fuel trims. I have added 8% fuel to maintain high 11 AFR's and can barley hit 20psi. I do have some STKR and LTKR but it's no more than I had with the stock manifold. My WGDC os maxxed at 95% with no deviation.

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This does not reflect negatively on the performance of the SDK manifold. It may only elude to the poor performance of the stock turbo.

how does the car feel? from what i can see it looks like the SDK manifold takes more time for the turbo to spool up. is that correct?

The car still feels strong, but there is no way to say if its a little bit stronger, weaker, or the exact same. And yes, it takes longer to spool, which is odd, this being such a small turbo.

I am perplexed.

Could it be that small amount of difference on the cam gears?

Don't remind me


No, I dynoed 275/423 on the current cam gear timing

It seems that the trend in ported applications is to sacrifice a few TQ for a few HP. Unfortunetly the only way to know for sure is the only tool I don't have. A dyno.

Duster suggested a heavier spring. Like AGP or S2. I am gonna try and get my hands on one locally and see how much of a difference it makes. The car is still strong, just how strong compared to stock manifold is the question.

By getting a higher flowing intake, your engine can now breath easier. But you small turbo can't provide enough air fast enough. It's the the reason your torque is lower. You have to find the balance of what you want. Being front wheel drive, I would go with a turbo that will give full boost at around 4000 rpm or slightly higher. This will help with traction issues in first and second gear as set boost won't be achieved. Once third comes in, it will be a good highway killer as full boost will stay longer and well into the upper rpms.

m3boost wrote:

By getting a higher flowing intake, your engine can now breath easier. But you small turbo can't provide enough air fast enough. It's the the reason your torque is lower. You have to find the balance of what you want. Being front wheel drive, I would go with a turbo that will give full boost at around 4000 rpm or slightly higher. This will help with traction issues in first and second gear as set boost won't be achieved. Once third comes in, it will be a good highway killer as full boost will stay longer and well into the upper rpms.

It's very refreshing to talk to someone locally who seems to know what they are talking about, Tech-wise.

I use the stock intake, it's a CAI from the factory, on the stock turbo there is very small gains to be had with an aftermarket CAI. (SRI's lose power)

My Torque on last dyno is higher, by a shit ton. I dyno'd 275Hp and 423Tq.

Now the front wheel drive aspect does benifet from lower boost in the lower RPM's on the streets, I will agree to that. I can adjust my boost for wherever I want it to peak, and however slow I want it to come on. Right now I keep it under 18psi until 3K and then ~20psi from 3 to 5K. On another note, if I had to wait until 4000 rpm's for full boost I would kill myself! Right now I can achieve about 16psi by 2800 rpms, then it skyrockets into infinity if I would let it. My Waste Gate Duty Cycle is super low since I made my own wastegate and lowered the boost. On 91 I get some pretty high temperatures without Water Injection. It's not a huge concern, as my E85 tune spanks all that is ass in the FF class.

In other news, I have a 16g on order, with a 39lb wheel. The fun level is about to go way up , and the traction level is about to go way down