Hey guys, just wondering about how much lower is the hp from a 8.6.1 b16a to lets say a 9.1 b16a. I wanted a 9.1 but ended up with an 8.6.1 ?

 

The off-boost power will be lower, but you'll be able to run higher boost on whatever grade fuel you run. I wouldn't worry about it too much though...

If the engine is still apart, you could have the block decked and head milled to recover a bit of that compression...just a thought

 

I hear a lot of people run the Wiseco's 8.8:1 for their builds and you're not that far off. Just boost another extra psi and you'll probably more than make up for the difference.

 

Ok the motors not apart i'm actually heading to get it tuned in a week or two. But i was just curious I knew that ment i would be able to boost more, but i was just wondering how much of a difference there was in the two. thanks guys

 

The naturally aspirated HP will be slightly lower, meaning the engine will make less power OUT of boost, but when you are in boost it will make little to no difference. Like Schister said, you will be able to apply more psi then someone running higher compression than you. In the end you are going to get around the same HP as 9:1, you will just have a Higher PSI #. The benefit is your tuner will have a larger margin to tune in. I have 9.8:1 in my engine and can't honestly say I notice a big difference between my car and the 9:1 cars in my group.

In the end I wouldn't stress it, just make sure your tuner knows what your C:R is (he should ask anyway).

 

I am at 8.5:1 now and it feels no different than when I was 9.0:1.

 

9.8:1 here and uber happy.



For street performance, its really not worth going so low on compression. Couldn't be more pleased with my setup.