major differences between 52mm and 58mm TB?
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,961
Likes: 2
From: Fort Knox
lol, not like I can do that bro. remember the slight "living in another country" problem I have 
I'll just buy a 52 mm, that way I won't have to worry about it. Sounds like from what everyone is saying that it's not worth the effort.
I'll just buy a 52 mm, that way I won't have to worry about it. Sounds like from what everyone is saying that it's not worth the effort.
Burning Brakes
Joined: Oct 2004
Posts: 1,019
Likes: 1
From: Weymouth Dorset
Hi there, one of our cars that we run here has a 383 in there afr 195 heads and a CC306 cam, amongst other things and that is running the stock TB and making over 400 bhp, bigger is not always better
Adrian
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,961
Likes: 2
From: Fort Knox
Burning Brakes
Joined: May 2009
Posts: 1,014
Likes: 7
From: Ft Wayne IN
There is a formula for all this.
It is a matter of cylinder volume and rpm's And yes a 383 will benifit from a 52mm. You could run a 48mm and be fine or a 58mm and be ok but in my mind for what it's worth a 52mm is idea. If you do a search there is more info on this subject. but the basic rule of thumb is the volume of air and how fast do you want to move it.
('http://golenengineservice.com/calc/calccarb.htm')
And yes a 383 will benifit from a 52mm. You could run a 48mm and be fine or a 58mm and be ok but in my mind for what it's worth a 52mm is idea. If you do a search there is more info on this subject. but the basic rule of thumb is the volume of air and how fast do you want to move it. ('http://golenengineservice.com/calc/calccarb.htm')
Racer
Joined: Apr 2003
Posts: 426
Likes: 0
From: Detroit MI
I have the Holley 52mm on my 86. It is a very nice piece. 
It replaced a very worn out stock unit that I decided not to rebuild.
To get the bellow back on the front of the Holley was a major pain.
You can search for the ways members here have gotten it to connect.
I used the boil it in water method.
Tip of the day--> put it on before you mount the throttle body on the car you need to move quick before it cools.
It replaced a very worn out stock unit that I decided not to rebuild.
To get the bellow back on the front of the Holley was a major pain.
You can search for the ways members here have gotten it to connect.
I used the boil it in water method.
Tip of the day--> put it on before you mount the throttle body on the car you need to move quick before it cools.
Last edited by -js-; Feb 25, 2010 at 08:23 PM. Reason: Added replacement for worn stock TB.
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
When I had my former late 86,I tried the 52 and 58 MM and was not happy.
The stock 48 flows more than enough air to sustain the TPI system and engine.It took a bunch of trial and errors to come to the conclusion that for everyday driving,the stock feels and runs best.
If you race the car and want every tenth on that drag time slip sheet,then maybe a larger TB might work for ya.But in everyday driving,you may even feel a slight loss of torque off line.
If you choose to use a larger TB,be SURE to set the minimum air adjustment,iac/tps and etc to make it work.If you dont,you will get a code 33 and the car will run like crap.You may have to trial and error it if it doesnt work the first few times.The code 33 wont be a MAF code,but a unrealistic airflow into the engine.
The stock 48 flows more than enough air to sustain the TPI system and engine.It took a bunch of trial and errors to come to the conclusion that for everyday driving,the stock feels and runs best.
If you race the car and want every tenth on that drag time slip sheet,then maybe a larger TB might work for ya.But in everyday driving,you may even feel a slight loss of torque off line.
If you choose to use a larger TB,be SURE to set the minimum air adjustment,iac/tps and etc to make it work.If you dont,you will get a code 33 and the car will run like crap.You may have to trial and error it if it doesnt work the first few times.The code 33 wont be a MAF code,but a unrealistic airflow into the engine.
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Burning Brakes
Joined: Oct 2004
Posts: 1,019
Likes: 1
From: Weymouth Dorset
It is a matter of cylinder volume and rpm's And yes a 383 will benifit from a 52mm. You could run a 48mm and be fine or a 58mm and be ok but in my mind for what it's worth a 52mm is idea. If you do a search there is more info on this subject. but the basic rule of thumb is the volume of air and how fast do you want to move it.
('http://golenengineservice.com/calc/calccarb.htm')
And yes a 383 will benifit from a 52mm. You could run a 48mm and be fine or a 58mm and be ok but in my mind for what it's worth a 52mm is idea. If you do a search there is more info on this subject. but the basic rule of thumb is the volume of air and how fast do you want to move it. ('http://golenengineservice.com/calc/calccarb.htm')
I know all about TB sizing, and FWIW I am running a Arizona Speed and Marine 54mm Billet TB on my 383, so in this case shiny is better as well
Adrian
Thread Starter
Drifting
Joined: Sep 2004
Posts: 1,961
Likes: 2
From: Fort Knox
If you choose to use a larger TB,be SURE to set the minimum air adjustment,iac/tps and etc to make it work.If you dont,you will get a code 33 and the car will run like crap.You may have to trial and error it if it doesnt work the first few times.The code 33 wont be a MAF code,but a unrealistic airflow into the engine.
Drifting
Joined: Feb 2008
Posts: 1,267
Likes: 27
From: Texas
I changed out my 48mm for a 58mm along with a bigger cam and HSR so I dont know what caused it but my throttle response is insane now.
I dont know if it gained any power but 1/10th throttle means 70mph now so easier on the foot lol
I dont know if it gained any power but 1/10th throttle means 70mph now so easier on the foot lol
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
http://www.thirdgen.org/tpimod2
Oh! and did somebody say shiny.. Sorry couldn't help myself
Advanced
Joined: Nov 2009
Posts: 56
Likes: 0
From: Louisville Ky
I installed a 52mm on my 86 L98. To get a quicker throttle response adjust the throttle position switch voltage to .64 no more than that or you'll get a check engine light. I have a few bolt on mods but thats it. I have not dyno yet after all the mods but it seems when I drive now there is a big WOW factor. There is a book by a division of Cottrell Racing Engines called TPIS that has all the info on test of the different size throttle bodies.
