Hi, i purshased rsm's 62mm throttle body and ported inatke manifold for my 98 sunfire 2200 automatic a few months back, it cost me alot of money and i dont notice any power gains, actually i think i lost power.
When i come on to the car, like give her off the line it boggs out bad, like it's sucked out or not getting the gas or something, like the car is really holding back; this should not be, i am suppose to gain power not loose power.
I had a garage professionally install these parts and i took it back to them and they put it on the scanner, could not find anything wrong, i reset my computer a few times by disconnecting the battery, it has been a bit better then the first day i got the stuff put in, but it still holds back when i give er; anyone exsperience this with rsm's tb and im on a 2200, or does anyone know what could be causeing this problem i am having?
thanks.




98 j-body sedan

yea.... if you read alot of the tb posts, thats what the subject is...

your car can only take in so much air... so adding a bigger opening does nothing but slow down velocity...

adding huge tb;s and such, slow down velocity....

sure you might get a higher hp number in the top end range, but you totally lose your low and mid range power, meaning you lose overall.


our cars dont have alot of power to begin with, if you shift your powerband to all top end, and you arent driving at 4000+ rpm ALL THE TIME

then you really arent taking advantage of the high torque or any of the hp.....



do a search on volumetric efficiency post its prob on page 2 or 3 now, or just use the search button and read most of the 2.2 TB posts...

Get a turbo kit and come back with a big smile!


N2O + Bolt-ons = 220Hp/250Tq

Coming Soon:HpTunersPro, EagleConnectingRods, WiescoPistons, 13sec2200

in a nutshell, bigger is NOT always better....

and like shown, you lost pretty much all your low end....


but like jamal said... good thing for boost, but n/a, not really practical to use..

Event is right if you search you will find a post called ::::::TB POLL:::::: i made a while back lots of people gave info on their personal set ups ei engine type, trans and, tb size and what they thought of it. I lost low end on my 2200 but one day it will help when i go boost ...but for now i just squeeze my bottle..........

Well terry denomme, What you are discribing in youre first post there, I am running a stock throttle body, I am getting the same results, I am running 01 cavalier 4 spd auto 2.2L as well, I notice even when I am going 40-65 mph I am getting a bog or lost power, Ive got 124,000 km's on my engine. Ive had my cavalier in the dealer to get 1 recall taken care of. They scanned the computer for codes, Nothing came up, The Gm mechanic took it out for a road test they say it nothing wrong with it.

I dont know.

you put a 62 mm TB on a 2200? or a 2.2 with nothing else done?

rich weeks wrote:Well terry denomme, What you are discribing in youre first post there, I am running a stock throttle body, I am getting the same results, I am running 01 cavalier 4 spd auto 2.2L as well, I notice even when I am going 40-65 mph I am getting a bog or lost power, Ive got 124,000 km's on my engine. Ive had my cavalier in the dealer to get 1 recall taken care of. They scanned the computer for codes, Nothing came up, The Gm mechanic took it out for a road test they say it nothing wrong with it.

I dont know.

yours might be something as simple as maintainence needs, plugs wires, icm, coil packs, etc...

mainly because yours is mid range which would normally be a loss of spark or something..




terry's is off the line which is very normal with stock engines and oversized TB....