3.4" to 3.2"

[Steven Monteith]

I have a 2000 GP top swap with a Gen3, xp cam, mild ported heads, 42lb injectors, HAI, headers. I switched from a 3.4 to 3.2 a while back and was always curious about how much of a power difference that makes. What do you guys think? How much HP? I'm sure its a decent gain considering I can feel a difference.


Also, I took out my CAT almost 2 years ago when doing exhaust work and the CAT sat outside on the side of my house for quite a while. Now it is time for emissions soon so I need to put it back on. Should I just get a new one in case it got clogged? If so where can I get a good OEM CAT that will not throw any codes...which is what I'm worried about.

[Nchristopherson]

Do you have a scanner? There is a cheap, effective one that involves buying a bluetooth dongle to plug into your OBD-II port and connect to an android powered device. That way you can tell if you're knocking, as well as a bunch of other stuff, including resetting DTCs. A knocking 3.2 is slower than a non-knocking 3.4.

[Bio248]

with a cam you should be able to run a 3.2 no problem.

[Steven Monteith]

Yes I have an aeroforce. I only get 2 degrees of knock around 70-80 with the weather being 110 degrees. I've been running a 3.2 for quite a while and I'm always scanning. In the winter I never got any knock. BUT my question is, around how much horsepower should I have gained going from a 3.4-3.2???? Just curious. It was putting out 256WHP with the 3.4...

[Fivefingerdeathpunch]

20?

[ctracer]

yeah you should be 270-290 depending on how your car runs with the 3.2.

[Steven Monteith]

I was thinking around 20 as well. When I was NA I did the hv3 and that was supposed to be around 20-30hp I think and it seems like the same HP gain. It runs really well in the winter. Phoenix AZ summers blow and make it seem a bit sluggish

[Steven Monteith]

Any suggestions about the CAT Converter???

[Austins01GP]

are you gonna remove the cat again when emissions are over?

mine sat around in the garage for 2 years and threw it back on and it was fine, phoenix is pretty dry id bet you could get away with it

cant hurt to look into the cat with a light and see if you can see any visible problems

[Steven Monteith]

I'll probably just leave it on. I just don't want to put it on and deal with it throwing codes.

[Slick2500]

What tests do they run? Visual? Sniffer? If they do a visual you could always get a fake cat. If they do the sniffer I would just put the cat back in.

[kamuletoe]

I feel for you on the heat bro. Not as bad as you up in Phoenix, but in Tucson we are getting around 105s. I can tell at night my car runs tons better. Ya know when the heat is not melting your face off!

[Steven Monteith]

Sniffer. Here in phx its 110 everyday. Still 100 around 11pm. Lol in the spring when the days were warming up but still had cold mornings and nights, thats when I could really tell the difference. It feels like a 20hp difference. Lol

[slimguns]

I'm NA right now but in NM with 100* temps and non-coated headers, I got 170* intake temps today! Talk about sluggish! :-/

[Steven Monteith]

Try having a supercharger then you will know what sluggish feels like. Lol when I was NA I never really felt much of a difference when it was hot

[Steven Monteith]

I put my cat back on today as well as a thrush glasspack with borla pro mufflers. I had flowmaster super 44s before which I hated!! No code is being thrown and I love the sound. Its so quiet compared to flowmasters. It has a calm rumble but not much noise when in the car driving. Now I realize how loud my supercharger is with my 3.2". Lol I love the loud whine with not much exhaust noise.

[MBruneaux]

I'm NA right now but in NM with 100* temps and non-coated headers, I got 170* intake temps today! Talk about sluggish! :-/

I always wondered if the A/C system could be routed to the intake just to drop air intake temp 10 to 20 degrees? But then it would be 130 Degrees in the car so maybe that would only be worth it at the track. Just for kicks run your
intake to your floorboard!!