Throttle body upgrade question?
Thread Starter
Instructor
Joined: Nov 2003
Posts: 130
Likes: 1
From: Warren MI
Throttle body upgrade question?
I am thinking of going to a 52MM throttle body should I buy an aftermarket or get a redone stock one. What brands are good and which are no good and who gives the most for the money? Thanks to all in advance.
Large Impressive Member
Joined: Jul 2003
Posts: 65,811
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Re: Throttle body upgrade question? (Rottweiler)
:lurk: Curious myself, haven't seen this subject hashed out for a while on here. What's your current mod level?
Team Owner
Joined: Jul 2003
Posts: 24,650
Likes: 8
Re: Throttle body upgrade question? (Corvette Kid NC)
As Ive been told, unless youve dont all the porting, polishing on the intake/runners/heads, as well as free flowing exhaust mods, it will only hurt your performance. The stock size is 48mm fyi.
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Re: Throttle body upgrade question? (RED-85-Z51)
As Ive been told, unless youve dont all the porting, polishing on the intake/runners/heads, as well as free flowing exhaust mods, it will only hurt your performance. The stock size is 48mm fyi.
Unless you have done some intake and exhaust mods to help it breath, I doubt you'll see any benefit from a larger throttle body.
Racer
Joined: Feb 2004
Posts: 445
Likes: 1
From: Atlanta GA
Re: Throttle body upgrade question? (Rottweiler)
I tried the 52mm throttle body upgrade on my 89 with only exhaust mods...took it off and put the stock TB right back on. I have no intentions of putting it back on until the intake work is done.
Now, I see that you have long-tube headers, so I can't really speak from experience when using a 52mm TB with long-tubes. Maybe there is a difference....I'm sure that others will chime in.
Now, I see that you have long-tube headers, so I can't really speak from experience when using a 52mm TB with long-tubes. Maybe there is a difference....I'm sure that others will chime in.
Burning Brakes
Joined: Jul 2002
Posts: 871
Likes: 0
From: Costa Mesa CA
Re: Throttle body upgrade question? (Rottweiler)
I got one from a guy who machines the stock ones out to 52mm and replaces the TB plates on an exchange deal for about $200. He did a nice job and I am pleased with the results. But unless you have other porting done, the 52mm TB only eliminates that part or the intake system as the bottle-neck. Without at least grinding away that barn-door in the plenum and larger runners (or porting the stock ones) I think you'll just spend your money needlessly and have idling probs to boot.
Do some more porting, get a good cam then get the new TB. You'll probably have to reset your TPS to 7.4V like I did to get it to idle properly.
You might even run into a stumble off idle that I attribute to a higher volume of air flowing past the throttle plates at that time causing a vacuum and holding them closed more than normal. A little helper spring will fix that.
BIG JIM
Do some more porting, get a good cam then get the new TB. You'll probably have to reset your TPS to 7.4V like I did to get it to idle properly.
You might even run into a stumble off idle that I attribute to a higher volume of air flowing past the throttle plates at that time causing a vacuum and holding them closed more than normal. A little helper spring will fix that.
BIG JIM
Pro
Joined: Sep 2003
Posts: 670
Likes: 1
From: charlotte nc
Re: Throttle body upgrade question? (Rottweiler)
I had mine bored to 52 mm because the throttle shaft was worn out and it was leaking air and sticking. My engine is stock and I can't tell any difference as I expected. I figured it was the most cost effective way to fix the TB and if additional mods are done in the future, I'll be set. BTW, you can have it bored to 50mm ifyou want. Car runs great now, fantastic idle, and excellent throttle response with no sticky throttle. :cheers:
[Modified by dwestsr, 12:06 AM 4/5/2004]
[Modified by dwestsr, 12:06 AM 4/5/2004]
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Burning Brakes
Joined: Nov 2003
Posts: 935
Likes: 2
From: Beverly, NJ
Re: Throttle body upgrade question? (BIG JIM 54)
I got one from a guy who machines the stock ones out to 52mm and replaces the TB plates on an exchange deal for about $200. He did a nice job and I am pleased with the results. But unless you have other porting done, the 52mm TB only eliminates that part or the intake system as the bottle-neck. Without at least grinding away that barn-door in the plenum and larger runners (or porting the stock ones) I think you'll just spend your money needlessly and have idling probs to boot.
Do some more porting, get a good cam then get the new TB. You'll probably have to reset your TPS to 7.4V like I did to get it to idle properly.
You might even run into a stumble off idle that I attribute to a higher volume of air flowing past the throttle plates at that time causing a vacuum and holding them closed more than normal. A little helper spring will fix that.
BIG JIM
Do some more porting, get a good cam then get the new TB. You'll probably have to reset your TPS to 7.4V like I did to get it to idle properly.
You might even run into a stumble off idle that I attribute to a higher volume of air flowing past the throttle plates at that time causing a vacuum and holding them closed more than normal. A little helper spring will fix that.
BIG JIM
:cheers:
Le Mans Master
Joined: Apr 2000
Posts: 6,341
Likes: 1
From: Shelton CT
Re: Throttle body upgrade question? (darkman5001)
I upgraded to an AS&M 52mm TB and could feeel a bit better throttle response off idle. No idea of any gains or losses as I did a lot of mods at the same time, but doing these pushed me from 13.3@103mph to 12.3@113.5mph
New dart iron eagle race heads
Breathless Air pump elim. kit
AS&M 52mm TB
New dart iron eagle race heads
Breathless Air pump elim. kit
AS&M 52mm TB
