Throttle Body-52mm 58mm
Thread Starter
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Joined: Jul 2016
Posts: 67
Likes: 12
From: Morganville NJ
Throttle Body-52mm 58mm
I have a 1993 C4 LT1
I see there are 2 sizes of TBs. What is factory and is there an option worth doing for better performance? I also see the airfoil gadget. Snake oil?
I see there are 2 sizes of TBs. What is factory and is there an option worth doing for better performance? I also see the airfoil gadget. Snake oil?
Le Mans Master
Joined: Jun 2009
Posts: 6,528
Likes: 752
From: South Dakota
The stock one is 48mm.
Unless your car has a lot of mods, there is no need to go to the bigger throttle bodies. The gains will be minimal if any.
The airfoil is poorly thought of on the forum. It adds very little if any to the performance and adds the possibility of the retaining screw coming loose and being ingested into the motor causing a catastrophic failure. I tried one a long time ago and the seat of the pants there was no gain. However there was enough difference in flow that I got a hesitation on first throttle movement. I changed the chip and the hesitation went away. So it does do something, but not enough to feel.
In short, they both will lighten your wallet without much gain.
EDIT:
Just saw you have 2 posts. Welcome to the forum.
We like pictures too, so show us yours and tell us about it.
Unless your car has a lot of mods, there is no need to go to the bigger throttle bodies. The gains will be minimal if any.
The airfoil is poorly thought of on the forum. It adds very little if any to the performance and adds the possibility of the retaining screw coming loose and being ingested into the motor causing a catastrophic failure. I tried one a long time ago and the seat of the pants there was no gain. However there was enough difference in flow that I got a hesitation on first throttle movement. I changed the chip and the hesitation went away. So it does do something, but not enough to feel.
In short, they both will lighten your wallet without much gain.
EDIT:
Just saw you have 2 posts. Welcome to the forum.
We like pictures too, so show us yours and tell us about it.
Last edited by QCVette; Mar 11, 2018 at 10:09 AM.
Team Owner
Joined: Dec 1999
Posts: 34,873
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The OEM throttle body is a 48mm size and it will work fine for a stock motor and for motors with some mods. If you have to replace the TB on your car, then a 52mm TB will work fine.
The "airfoil" is all but worthless. Don't bother with one as you will not see anything in the way of a performance increase.
If you want some mods for your car, I would suggest starting with headers and a true dual exhaust system. Do you have to have any sort of emissions testing where you live? With long tube headers, you can remove the cats and center resonator and install true dual exhaust with an X-pipe.
Also, it can't hurt to replace the plug wires and spark plugs. MSD and Taylor make good 8mm wire sets. Use Iridium plugs such as those from NGK or even AC Delco.
The "airfoil" is all but worthless. Don't bother with one as you will not see anything in the way of a performance increase.
If you want some mods for your car, I would suggest starting with headers and a true dual exhaust system. Do you have to have any sort of emissions testing where you live? With long tube headers, you can remove the cats and center resonator and install true dual exhaust with an X-pipe.
Also, it can't hurt to replace the plug wires and spark plugs. MSD and Taylor make good 8mm wire sets. Use Iridium plugs such as those from NGK or even AC Delco.
Thread Starter
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Joined: Jul 2016
Posts: 67
Likes: 12
From: Morganville NJ
Thanks for the answers. The car runs pretty good. It has 67k on it and is stock. I'm in the middle of getting it back to a reliable condition like replacing hoses, lines, and tune up parts. And in NJ we don't do inspections on vehicles over than like 20 years so I could get away with certain mods. Building a garage this summer so I can work more comfortably on it.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I could send you $1 and still be within the "UP TO" stipulation. Good stuff isn't cheap because it doesn't have to be. Cheap stuff isn't good because it can't be. General rule I live by.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Thanks for the answers. The car runs pretty good. It has 67k on it and is stock. I'm in the middle of getting it back to a reliable condition like replacing hoses, lines, and tune up parts. And in NJ we don't do inspections on vehicles over than like 20 years so I could get away with certain mods. Building a garage this summer so I can work more comfortably on it.
As the priest joke goes, I'm asking this for a friend.
My $0.02, get the plugs, done with something decent but not exotic. Change them every couple of years. Flush anything fluid. Spray a fine mist around the plug wires when it is cold and when it is hot in a dark garage to see if there is any leaking. Check fuel pressure. Change brake hoses. I dump all my injectors when I get a new car for reman units because they will have some build up that I don't trust snake oil to remove.
Last edited by aklim; Mar 11, 2018 at 10:31 PM.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
He did threaten to make me walk home if he heard another word about it on the way home. So funny. Never heard it being faster any more. Bought it from him later when mine was having issues. All for a song.
Last edited by aklim; Mar 12, 2018 at 09:17 AM.
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Advanced
Joined: Oct 2017
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Thanks for the answers. The car runs pretty good. It has 67k on it and is stock. I'm in the middle of getting it back to a reliable condition like replacing hoses, lines, and tune up parts. And in NJ we don't do inspections on vehicles over than like 20 years so I could get away with certain mods. Building a garage this summer so I can work more comfortably on it.
Le Mans Master
Joined: Sep 2013
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From: near the thumb in the mitten
If the engine only requires 600 cfm installing 750 cfm may cause a loss of performance. ECM calibration will be off a little, on initial acceleration due extra air. The main performance benefits are at 85% + throttle, when requires maximum airflow. One other possible situation is the outside of throttle body is usually larger than the stock one. Many times the stock air filter ducting won't fit over it.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
If the engine only requires 600 cfm installing 750 cfm may cause a loss of performance. ECM calibration will be off a little, on initial acceleration due extra air. The main performance benefits are at 85% + throttle, when requires maximum airflow. One other possible situation is the outside of throttle body is usually larger than the stock one. Many times the stock air filter ducting won't fit over it.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
I do not. I do have a 52mm on an LT4 intake I don't know who made it(don't have it's cover) but it's too big. I have read of others who have had similar condition with the larger throttle body.
Team Owner
Joined: Jul 2004
Posts: 28,475
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From: Hartford WI
I have a K&N 5050 conical filter so it is a c-hair looser but you just got me worried that if the bore were large enough, it too might not fit and who knows if they will still make what I have that does fit.