TB size
04-03-2007, 08:31 PM
#4
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Join Date: Feb 2004
Posts: 4,800
With port injection it would be for all practical purposes be impossible to go too large. It is not like a carb where you need some velocity to atomized fuel in the intake.
That said a 58mm isn't going to do a lot for a bolton car.
That said a 58mm isn't going to do a lot for a bolton car.
04-03-2007, 11:36 PM
#6
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Last edited by Joe B; 04-03-2007 at 11:42 PM.
04-04-2007, 06:45 PM
#10
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Join Date: Feb 2004
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Since on the subject. If looking at 52mm rebore the stocker, if looking to buy skip right to 58mm.
Aftermarket TBs are not 100% bolton with TPS and IAC issues to tweak so why spend the coin for a new 52mm with those issues when for a lot less there are a lot of places that will rebore a stocker that will bolton and be ready to go.
I would honestly have a rebored stocker had I not come across the 58mm for less than a rebored stocker would have cost.
Aftermarket TBs are not 100% bolton with TPS and IAC issues to tweak so why spend the coin for a new 52mm with those issues when for a lot less there are a lot of places that will rebore a stocker that will bolton and be ready to go.
I would honestly have a rebored stocker had I not come across the 58mm for less than a rebored stocker would have cost.
04-04-2007, 09:46 PM
#11
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Location: Burlington, NJ
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no...too big a tb has THE SAME EFFECTS FOR FI AS CARB'D. you wont have any problems as you slightly go from fully closed to fully open, but try that crap with a 0 to WOT situation and you'll get bogged down. there's simply too much air for the cylinders to mix the fuel properly with. there's too much air and not enough fuel....boggin down.
04-04-2007, 10:01 PM
#12
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then i guess that's why there's no issue with "tip in hesitation" with a large or oversized throttle body? i assume that anyone who's had a stall or sputter because too big a tb was installed shpuld look into other problems?
no...too big a tb has THE SAME EFFECTS FOR FI AS CARB'D. you wont have any problems as you slightly go from fully closed to fully open, but try that crap with a 0 to WOT situation and you'll get bogged down. there's simply too much air for the cylinders to mix the fuel properly with. there's too much air and not enough fuel....boggin down.
no...too big a tb has THE SAME EFFECTS FOR FI AS CARB'D. you wont have any problems as you slightly go from fully closed to fully open, but try that crap with a 0 to WOT situation and you'll get bogged down. there's simply too much air for the cylinders to mix the fuel properly with. there's too much air and not enough fuel....boggin down.
I don't have a problem. I usually don't go from idle to WOT though on the street even from a coast that will result in the rear sliding around, on the track I try to load it up a little for slightly less shock on the drivetrain.
The MAF sees the air flow the pcm adds fuel. If you have tip-in issues first clean the MAF then double check mechanical issues and tuning. What do I know though I actually have a 58mm?
04-04-2007, 10:42 PM
#13
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Join Date: Oct 2004
Posts: 340
Actually, on our local board, a dyno test was done between stock, 54mm and 58mm throttle bodies.
The 58 actually gained i think 10rwhp and 15 tq or something like that over stock.
The 58 actually gained i think 10rwhp and 15 tq or something like that over stock.
Last edited by RedsTA; 04-04-2007 at 10:46 PM.
04-05-2007, 02:02 AM
#14
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Join Date: Oct 2005
Posts: 414
then i guess that's why there's no issue with "tip in hesitation" with a large or oversized throttle body? i assume that anyone who's had a stall or sputter because too big a tb was installed shpuld look into other problems?
no...too big a tb has THE SAME EFFECTS FOR FI AS CARB'D. you wont have any problems as you slightly go from fully closed to fully open, but try that crap with a 0 to WOT situation and you'll get bogged down. there's simply too much air for the cylinders to mix the fuel properly with. there's too much air and not enough fuel....boggin down.
no...too big a tb has THE SAME EFFECTS FOR FI AS CARB'D. you wont have any problems as you slightly go from fully closed to fully open, but try that crap with a 0 to WOT situation and you'll get bogged down. there's simply too much air for the cylinders to mix the fuel properly with. there's too much air and not enough fuel....boggin down.