Ok, I have a 00' EX Civic with a SRI, HP Racing header, 2.25" exhaust, 9.3mm plug wires and NGK plugs. Im guessing that Im pushing maybe around 145hp at the most. The car comes stock with 127hp. Im thinking about getting a TB spacer, AEM underdrive pulleys, and a test pipe. Would that help me any...? If not then please tell me some small things like that I could get to help me out a little for now. Thanks guys

 

u can try a cai and a intake manifold u can change the spark wires and fuel rails also as far as the aem pulleys i have a 2000 si and i read that the unorthodox pulleys have better results than the aem just from what i read u can check it out to they r more expensive but i heard it does a better job.

 

yea I already have changed the spark plug wires, I have 9.3mm over the 7mm that comes on there. I really don't think an intake manifold is going to do that much for me without some kind of forced induction but I dunno. I might. Thanks for the info anyway man...know anything about the throttle body spacer or the test pipe tho? How much hp do they add?

 

i don't know much about test pipes so i am not going to lie and tb i heard the bigger u get the more hp and i know with the intake maifold the claims it at like 10-12 hp but i have a dohc so i don't know the results 4 a sohc

 

k cool thanks. I'll check on it

 

You really won't see enough of a gain from a test pipe to warrant polluting with no cat. They make high flow cats and they only cost a little more, look into those if you are set on replacing the cat, unless you only want it for the track then go for it. Right now I think your best bet would be a new throttle body and intake manifold. Skunk2 has dynos at +12 Hp to the wheels with their IM. If you but a big bore TB on there you could be looking at 17-18. Throttle body spacers are a cheap bolt-on but I wouldn't expect more than 1-2 Hp from them. The "swirling effect" that they supposedly produce actually restricts airflow, but it increases volume and more importantly cools the incoming air. If you do get one I would grind it smooth.

 

thats true what sniper said cause i did the same thing with the grinding on my tb and it helped a bit and after u get a intake manifold and db u should see around 15-18 well thats what i got when i dyno it i still have some work going on with these issues but what kind of maifold and tb was u thinking of

 

I meant grinding the TB spacer smooth so it didn't have those swirly ridges, but port matching the TB is a good idea too.

 

Sniper, if you grind off the ridges that swirl the air, how does the TB spacer do any good? I'm not bashin you, I'm just curios cause I thought that's the purpose, to swirl the air and mix the air with the fuel better.

 

I read this from an idependant dyno test that measured airflow as well as Hp. The ridges actually restricted the airflow by like 6% but the increased volume and cooling effect it had increased the Hp by about 2Hp. After they ground down the edges a bit to make them smooth the air flowed better and they got another 2-3 Horse from it. Lemme see if I can find the link. It was on a Jeep but airflow is airflow.

EDIT: here it is. Good stuff. TB Dyno