i jus wanted to clarify something before i go ahead with it, i got ahold of 57mm about to be installed b4 the car comes back out, so far my modifications are

WAI
upper and lower mounts
full 2.5" exhaust, magnaflow cat,
b/m shift plus kit


jus wondering, with the 57mm tb now, should i expect to notice a difference in the top end, i know it wont help trq, but im jus lookin for some insight as to how a 57mm will benefit me, thanks

not to thread jack but basically the same question....i put the HO on with the 59mm tb and wanted to see if it helped or hurt me....feels a little faster but that could be in my head

i have WAI, the TB, HO Intake mani, solid mounts, high flow cat, and the rskport boots and inserts



2007 GM Tuner Bash...HELL YEA
PA,MD,NJ,DE,NY and all states north caravan

As you stated, your torque numbers are suffering/will suffer from the lack of backpressure. The 2.5" exhaust may be what is hurting you the most (unless you're preparing to boost in the future). Backpressure is not the only important aspect, velocity and volumetric efficiency are as well. If enough air isn't being forced into your engine fast enough then its bad news for your hp and tq numbers.

The 57mm throttle body for the 2.4 (which is your engine, I'm assuming) should be fine and will help open up your motor and help your top end. TB's larger than a certain size will not move the air in with a high velocity and will, therefore, cause a power drop. TB's smaller than a certain size will not move enough air, thereby causing a power drop.



Blown.

The HO mani is supposed to be a good upgrade and it'll definitely help open up the engine. But the phrase "bigger is better" shouldn't be taken into account in this case. TB's in general have to follow a specific formula, which is outlined quite well and discussed in good detail in this thread: clicky .

The 57mm TB should be alright and the HO mani with the 59mm TB should do well, too. They'll help out in top end but don't expect big gains unless you're boosted simply because the engine can only move so much air. A boosted vehicle will move that much air and then some. TB's are supposed to flow a certain amount of air and too large or two small will hinder the engine.



Blown.

thanks man, and yes boost is in the future, as well as ive heard a lot bout 59mm being the biggest i would wanna go for now, so 57mm should be enuff to give me a nice gain, and alot of peeps say 2.5" was to big, but i noticed a nice diff so was happy with it

thanks man



2007 GM Tuner Bash...HELL YEA
PA,MD,NJ,DE,NY and all states north caravan

No problem..I hope it wasn't confusing. I'm horrible at trying to explain things.



Blown.

Good job Filip

Also a side note, it will possibly shift you powerband slightly upwards...so when he says loss of torque, that's because your powerband has shifted into higher RPMs.



www.kronosperformance.com / 732-742-8837

thanks!!

NJHK (The JBO Negro) wrote:Good job Filip

Also a side note, it will possibly shift you powerband slightly upwards...so when he says loss of torque, that's because your powerband has shifted into higher RPMs.

Thanks Adam, I appreciate it. And darn it, I knew I forgot to mention something, thanks for that bit of info!



Blown.