I have the 68mm Throttlebody from the Cobalt, 2.0L SC installed on the Ecotec 2.2. It has much improved the low to mid pull but after 5k RPM there is a loss of torque. I have a the standard head but have modified the intake and am running with a sport exhaust with a 200 Cell CAT.
Anybody any ideas why this is happening?
Power Curve
Thats kinda like what happens to the 2.2L Eco with the 62mm TB from RSM or Reveco. Except I think the gains/losses are the opposite to yours, lol. Basically, from what i've read, if you're still N/A you don't need a larger TB, only should you go with forced induction or perhaps nitrous will you need a larger TB. Thats what my understanding of the "situation" is. I'm no expert though so I'd wait for a few more responses, lol.
Not sure why you would go with such a large TB on a N/A set-up. I would think you would have more low-end loss, and maybe some gains in the top end. Remember torque does not always pull as far as HP
FU Tuning
^^^ Thats exactly what I thought, I wonder if there would be a difference between the 62 and 68mm TB's. If there is then I think I need to go to the scrapyards and look for a wrecked 2.0L SC'ed motor.
Alex wrote:^^^ Thats exactly what I thought, I wonder if there would be a difference between the 62 and 68mm TB's. If there is then I think I need to go to the scrapyards and look for a wrecked 2.0L SC'ed motor.
You cant take a ss/sc TB, theyre drive by wire.
Check out my car....
http://members.cardomain.com/o4blackfire
He has a Vauxhall...he can take a SS/SC TB and make it work. Also IIRC the Vauxhall Speedster revs to 7000+ correct? It also has a slightly different head IIRC. It feeling faster probably means it can use the added air down low but gets choked up top or something. Exactly the opposite of ours which needs more air up top. That or your butt dyno is broken
I used to race cars, now I race myself.
5K PB: 24:50
10K PB: 54:26
the lager tb isnt worth much on the bottom end unless your under boost , more so on a s/c
i think the 2.2 drive by wire and the 2.4 use a smaller tb than the 2.0 , but im not 100% sure
Team Vision Racing (aka hypsy) wrote:He has a Vauxhall...he can take a SS/SC TB and make it work. Also IIRC the Vauxhall Speedster revs to 7000+ correct? It also has a slightly different head IIRC. It feeling faster probably means it can use the added air down low but gets choked up top or something. Exactly the opposite of ours which needs more air up top. That or your butt dyno is broken
There is definitely an improvement up to 5k but she looses some torque beyond, compared to what she pulled like with the standard 52mm TB attached. I am running with a wideband plus SAFC-2 and the AFR is OK. BTW the rev limiter cuts in at 6800. I thinking of going for a JBP race head, don't want forced induction. Hopefully this will improve the top end. Can I achieve anything by a timing adjustment?
Power Curve
id go with the Patriot stage II head honestly
The one, the only, ME.
,
F$%K ILLSTREET.COM
ok.. the problem is... your car... u need to trade it for a cavalier... this way u wont have that problem.....id be more then willing to trade cars to help you out!
John H [Cavalierkid wrote:]ok.. the problem is... your car... u need to trade it for a cavalier... this way u wont have that problem.....id be more then willing to trade cars to help you out!
lol! let me think about that one :p
Who is selling the Patriot? I need a dealer who can ship over the pond!!
Power Curve
Here's an LM-1 log of a third gear pull
Power Curve
Green is the MAP sensor output
Blue is the SAFC-2 output
Red is throttle position
Black is RPM
Purple is AFR
Power Curve
afr looks on the rich side for a n/a motor , you want it close to 13.0
[quote=97cavie24ls(JDM&00s/c sedans™)]afr looks on the rich side for a n/a motor , you want it close to 13.0
I agree. I need to get something more sophisticated than the SAFC-2 to complete my tuning. If I pull the MAP sensor input back any further to try and adjust back the AFR the PCM fires a low MAP sensor volatage code and shuts down the fueling.
Power Curve
I sell the Patriot heads. It will be expensive to ship to England but I have no problem doing it if you pay the charges
I used to race cars, now I race myself.
5K PB: 24:50
10K PB: 54:26
dude your car is the @!#$...
