any other mods to help ie air intake or afpr etc.. I have contemplated this but wasn't sure if it was worth it without some other mods
Installed The 52MM TB Today
Thread Starter
Team Owner
Joined: Jan 2003
Posts: 20,315
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From: Summerland B.C. Canada
Installed The 52MM TB Today
I finally got around to cleaning up the 52mm TB i bought from Draven.
Yes, i noticed a definite improvement in performance.
I bought it in the hopes that whoever bored it put in sealed bearings in the shaft bores. Draven didn't know but for the price i decided who cares. If the shaft bore is in better shape than mine and it's 52mm with a the infamous AIR FOIL, i can't cry 
The throttle plates had a little binding when closed so i took a little emery to a few spots on the edges and it works smooth now. My idle doesn't take so long to return now and the performance improvement is good. Here's a few pics
Here is the 48 with the 52
The "No turning back bypass" installed on the 52
The 52 cleaned up
Yes, i noticed a definite improvement in performance.
I bought it in the hopes that whoever bored it put in sealed bearings in the shaft bores. Draven didn't know but for the price i decided who cares. If the shaft bore is in better shape than mine and it's 52mm with a the infamous AIR FOIL, i can't cry The throttle plates had a little binding when closed so i took a little emery to a few spots on the edges and it works smooth now. My idle doesn't take so long to return now and the performance improvement is good. Here's a few pics
Here is the 48 with the 52
The "No turning back bypass" installed on the 52
The 52 cleaned up
Melting Slicks
Joined: Nov 2003
Posts: 2,679
Likes: 1
From: South Amboy NJ
looks good....how do you change the shaft bearings....they seem shot on my trans am and i was contemplating buying a new (used) tb but if i can just replace the bearing that would be a lot better.
Thread Starter
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Originally Posted by BlackRoseLT1
looks good....how do you change the shaft bearings....they seem shot on my trans am and i was contemplating buying a new (used) tb but if i can just replace the bearing that would be a lot better.
Thread Starter
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Originally Posted by Spankyellow
Looks like you got a good deal. Will you make it to the dragstrip and get some numbers for us ?
Team Owner
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Originally Posted by AGENT 86
I'm going to make it sometime this summer. Never been before so i can't compare #'s. I will take both TB's and compare
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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
I knew when I saw the first pic of the TB that before the progression of pictures was over, it'd be nice and clean. I had a 58 on my car for a while. Didn't really like it although it may have helped on the big end. I've got a modified to 52 stocker on the way and now I'm even more anxious to get it on.
I had a 58 on my car for a while. Didn't really like it although it may have helped on the big end. I've got a modified to 52 stocker on the way and now I'm even more anxious to get it on.
Drifting
Joined: Jun 2001
Posts: 1,997
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From: Lake Ozark MO
I also recommend David Koldos. His work is exceptional.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
Thread Starter
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Originally Posted by Dan Parker '96
I also recommend David Koldos. His work is exceptional.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
but i do notice a difference. I'm not saying it adds gobs of extra power but it has changed the way may car reacts. What i noticed was when stomping the pedal with the rpm in the 3000 area the engine had more grunt and would clime to 5000 rpm quicker than before. Call me crazy but when cruizing at about 50 mph and stomp it now it's almost like the feeling of the auto kickdown of my 4+3 
Drifting
Joined: Dec 2002
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From: Tracy CA
The throttle response is much faster with a larger bore throttle body. The manifold hits zero vacuum at a lower throttle position. It's a similar effect of changing the throttle body cam so that it's not linear. (4 banger cars in the 80's did this alot to make them seem more powerful than they were. The first inch of pedal opened the throttle blades 50% the remaining 4" of travel made it to 100%.)
In terms of absolute power - I've heard that they don't help at all till the mods are over the top.
Now that I've poo pooed all your hard work - it does look awesome!
In terms of absolute power - I've heard that they don't help at all till the mods are over the top.
Now that I've poo pooed all your hard work - it does look awesome!
Le Mans Master
Joined: Jul 2002
Posts: 5,818
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From: Alive and well in Burlington NC
Originally Posted by AGENT 86
It may be the placebo affect but i do notice a difference. I'm not saying it adds gobs of extra power but it has changed the way may car reacts. What i noticed was when stomping the pedal with the rpm in the 3000 area the engine had more grunt and would clime to 5000 rpm quicker than before. Call me crazy but when cruizing at about 50 mph and stomp it now it's almost like the feeling of the auto kickdown of my 4+3
but i do notice a difference. I'm not saying it adds gobs of extra power but it has changed the way may car reacts. What i noticed was when stomping the pedal with the rpm in the 3000 area the engine had more grunt and would clime to 5000 rpm quicker than before. Call me crazy but when cruizing at about 50 mph and stomp it now it's almost like the feeling of the auto kickdown of my 4+3
Le Mans Master
Joined: Jul 2001
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From: Stamford VT
Originally Posted by mitchcole
The throttle response is much faster with a larger bore throttle body. The manifold hits zero vacuum at a lower throttle position.
Safety Car
Joined: Sep 2000
Posts: 3,524
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From: Hinckley Ohio
Originally Posted by Dan Parker '96
I also recommend David Koldos. His work is exceptional.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
I really don't understand your comments.....it is still my thinking that you don't want your MAP to drop at WOT, so if a bigger tb shows an increase in MAP at WOT the bigger tb was beneficial.
A perfect intake, IMHO, would be if the MAP reading stayed constant from low rpm to max rpm, at the same value as the barometer or MAP with the motor off
???????
Safety Car
Joined: Sep 2000
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From: Hinckley Ohio
Originally Posted by Corvette Kid NC
I had a 58 on my car for a while. Didn't really like it although it may have helped on the big end. I've got a modified to 52 stocker on the way and now I'm even more anxious to get it on.
Did you bore your intake openings out to 58mm??? A 58mm tb on 52mm openings doesn't work......seems to cause turbulance in air flow making the 58 worse than the 48....
Safety Car
Joined: Jun 2004
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From: lafayette co
Originally Posted by Dan Parker '96
I also recommend David Koldos. His work is exceptional.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
As far as a performance gain going from 48mm to 52mm, you'll see none. At least as far as an LT4/Hotcam combo cares. Data logging may show a slight increase in MAP pressure but it's not realized by the rest of the package.
http://forums.corvetteforum.com/show...bk&forum_id=48
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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
Originally Posted by LT4BUD
Why didn't you like it????
Did you bore your intake openings out to 58mm??? A 58mm tb on 52mm openings doesn't work......seems to cause turbulance in air flow making the 58 worse than the 48....
Did you bore your intake openings out to 58mm??? A 58mm tb on 52mm openings doesn't work......seems to cause turbulance in air flow making the 58 worse than the 48....