What size T/B
Thread Starter
Burning Brakes
Joined: Nov 2003
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From: Cape Cod Ma
What size T/B
What size throttle body should I get? I have a mini-ram, trick-flow cnc'ed heads. everything port mached. TPIS cam around .589"in, .559ex or so with the 1.6 rr. 13/4 hooker headers, all forged bottom end 4 bolt mains. Everything else is done up but I still have a stock T/B 48mm.
I think most of you guy's will say the 52mm one but places like lingenfelter, tpis say go the 58mm t/b for a high performance application.
I drive mostly on the street. Would I have too much throttle response with the 58mm one? But what is too much? Can't be that much.
I think most of you guy's will say the 52mm one but places like lingenfelter, tpis say go the 58mm t/b for a high performance application.
I drive mostly on the street. Would I have too much throttle response with the 58mm one? But what is too much? Can't be that much.
Instructor
Joined: May 1999
Posts: 206
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From: Lebanon Ohio
See now Id do a 58.... with the amount of lift of the cam...flow of the heads/mini ram Id do the 58...Even though you are slightly under what would necessitate a 58 it wont hurt you and it gives you room to grow>>
If you want the 52 MM I have a number somewhere of a shop that cheaply converts your 48 to a 52...it costs a fraction of what a new one costs.. Either way there are places all over the net that convert stockers to 52mm versions.. Its a waste to pay BBK or whoever 320 for the same thing.. Ive even seen shops that convert stockers to monoblades which a 48MM opened to a monoblade flows about the same as a twin 58... if you have them bore each to 52 then cut the center it outflows the 58>>>>Those are the ones that AS&M used to sell as well as the TPIS special order one..
If you want the 52 MM I have a number somewhere of a shop that cheaply converts your 48 to a 52...it costs a fraction of what a new one costs.. Either way there are places all over the net that convert stockers to 52mm versions.. Its a waste to pay BBK or whoever 320 for the same thing.. Ive even seen shops that convert stockers to monoblades which a 48MM opened to a monoblade flows about the same as a twin 58... if you have them bore each to 52 then cut the center it outflows the 58>>>>Those are the ones that AS&M used to sell as well as the TPIS special order one..
Thread Starter
Burning Brakes
Joined: Nov 2003
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From: Cape Cod Ma
To me the 52mm seems worthless for a high rpm motor. 48 to 52 dosnt seem like much. But I don't know i havent owned anything bigger than stock size. For the same amount of $ you could either have a 52 or 58mm t/b new. The reason I posted this is that I see mostly everyone running the 52mm version.
Instructor
Joined: May 1999
Posts: 206
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From: Lebanon Ohio
FWIW on my 400 SBC turbo GTA I use a 90MM tb one the street... I dont notice any throttle response issues... a single 90MM greatly outflows a twin 58...
I dont believe you will have any worries.. There were/are guys bolting them on essentially stock LT4 setups and showing soliid gains with them..
Again all that will happen if you buy the 52 is somewhere shortly down the road you go to mod it more and then NEED the 58 and be sorry you did not get it in the first place..
If you do the generic area formula it shows( I dont have the CFM charts handy but this illustrates what the area of the hole is )
48MM twin = 3617.28
52 mm twin = 4245.28
58 mm twin = 5281.48
And for fun
90MM single = 6358.5
looking at the numbers you are right in that the 52 is much closer to the 48 than the 58..
I dont believe you will have any worries.. There were/are guys bolting them on essentially stock LT4 setups and showing soliid gains with them..
Again all that will happen if you buy the 52 is somewhere shortly down the road you go to mod it more and then NEED the 58 and be sorry you did not get it in the first place..
If you do the generic area formula it shows( I dont have the CFM charts handy but this illustrates what the area of the hole is )
48MM twin = 3617.28
52 mm twin = 4245.28
58 mm twin = 5281.48
And for fun
90MM single = 6358.5
looking at the numbers you are right in that the 52 is much closer to the 48 than the 58..
Thread Starter
Burning Brakes
Joined: Nov 2003
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From: Cape Cod Ma
I agree with you guy's about the 58mm. But i've been told that the 58 will give me too mutch throttle response on the street. I can't see why that would be if companies make em as big, to say your 90mm one.
Thread Starter
Burning Brakes
Joined: Nov 2003
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From: Cape Cod Ma
Also to the second post ( no bad mouthin) I also didn't say my rpm ranges. But my modded 350 makes peek power at around 6,500rpm. So why would a 52mm be better on mine and a 58 be better on a 383ci. Wouldn't my engine combo choke out quicker with a 52 than the 58mm? More air+ more fuell = more power right? Or not?
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Melting Slicks
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From: What did the 5 fingers say to the face? SLAP!!
Originally Posted by redfast
places like lingenfelter, tpis say go the 58mm t/b for a high performance application.
58mm is what you need...
