carb and fuel set up? for a straight 6, 82 fairmont 1bbl.

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ryan11

New member
carb and fuel set up? for a 1bbl holley 1946, straight 6 82 fairmont.

looking to boost a carbed 82 fairmont straight 6, cheaply on low boost, a small turbo and run blow thru style.

a little bit about my boost history,,,, i have boost alot of fuel injected cars, and have built all kinds of different set-ups,mostly homebrewed set-ups,,ranging from fmu's to megasquirts and also safcs, logs to ramhorn manifolds,small and bigger turbos,ect,ect. (also look at my 1st post in the intro forum to read more about me.)
so i have been in the turbo game for a while, but never even thought about a carbed set-up and have not really searched about it untill a few days ago.

so to the fairmont project, plans are keep the 1bbl holley 1946, and run a small
.42/.48 t3 only looking to go 8-10 psi,make a carb hat,run a boost ref. fuel regulator and a efi pump and run the return line back to the fuel tank filler neck, and lock the dizzy at a safe time.

from what i have read the 1bbl holley 1946 has a float that is fine for boost, so is there anything else i need to do to to make the carb ready for boost?
with running the carb hat and boost ref regulator also.

is there anything else im missing, carb and fuel wise to make this work?
 
wallaka":2jwluwsp said:
Have you read the sticky at the top of the forum? He details your scenario exactly.
Click to expand...

yes i have, along with others carbed turbo post on here and the turboforums in the carbed section.
im new to carbs let alone modding them for boost, or anything carbed+boost related, fuel injected boosted cars i have done for some time now, its just the whole carb deal im new too..
thanks
 
Google holley carb tuning.

It will mostly be about 4bbls, but the same principle applies for the 1946.

Basically, the hardest thing to do is get the power valve mixture set correctly so it gives you the right amount of fuel under boost. If your looking to run 10psi, run an external EFI pump, with a regultor and return. Its less of a job to do that than to replace the HG because you leaned out from not getting enough fuel from the referenced fuel pump.

Other than that, running a blowthrough setup is dirt easy.

Make sure you limit timing via the centrifugal advance slots on in the distributor, you only want about 22* or so of advance at 10 psi. So putting a 12L or 10L slot in the distributor and running 10 or 12* base in the dist will give you that, make sure you leave the vacuum advance off the dist.

Anything beyond those two is pretty much the same as any other turbo setup.
 
Running a 10L or 12L centrifical slot will yield too much mechanical advance, as the slot values are doubled at the crank.. A 10L slot is 20 degrees crank rotation degrees, and a 12L is 24 degrees. As done in another turbo post, I suggest measuring the slot length, or find the reference within this forum, weld and file the slot to yield 10 degrees advance. I did this with my 13L, it was well under half the original slot length, and I’m running 16 degrees static with a Mr. Gasket 925 spring kit installed, but only running 7 PSI currently. As the others said, the 1946 set-up for blow-through has been detailed in other posts, should be very easy for an EFI guy, make sure you block off all the vacuum ports, I epoxied mine. Plan on drilling your jet out to get a safe tune, and definitely plan on purchasing a wideband, don’t try without one, otherwise you will very likely cause damage. Make your carb hat as unrestrictive as possible, no smaller opening than your carb venturi, and avoid sharp inlet angles. I would also plan on an intercooler if you are going 10 PSI. I would even run a smaller turbo since you have a 200 and only shooting for 8-10 PSI, perhaps a T28 or Mitsubishi 16G. These I6 engines really do not rev very high and it is nice have near zero lag, it makes the engine much more efficient , even when your still running on the vacuum side of the gauge. Sorry these responses do not directly relate to your carb question, good luck have fun!
 
thanks alot guys, i really appreciated it,,right now im finishing up a restoration on my 88 mazda 323 gtx awd.
yesterday i epoxy primed all the susp. parts + some other parts and did the hole bottom of the car. i built this cool car tilter out of wood and have the car tilted on its side.

but back to the mont, right now im just gauging roughly how much this project will cost 1st.
by the looks of it i could probably build everything for around 3-400ish or less which is good, i have a extra i.c.,bov,turbo and a bunch of exh. pipe leftovers from other projects.

i will not be building this untill spring, 1 cause i have to finish the gtx, and 2 i live in wi and the car is in the backyard covered in snow and behind a wooden fenced in area.

i had planed on locking the dizzy down, i will have to do some more reseach about carb hat size, and general info about the I6, i don't even know when the motor runs out of steam, but i figured it wasn't a high rever. and yes i want instant/low rpm boost so i figured the .48 t3 should spool pretty quick.

how many of you dd your boost carb car and what the mileage like?

what years did the I6 not come with the cated exhaust manifold and are they hard to find? i could just serach for this myself if no ones wants to bother.
 
351 celi":8lazlzkz said:
Running a 10L or 12L centrifical slot will yield too much mechanical advance, as the slot values are doubled at the crank.. A 10L slot is 20 degrees crank rotation degrees, and a 12L is 24 degrees. As done in another turbo post, I suggest measuring the slot length, or find the reference within this forum, weld and file the slot to yield 10 degrees advance. I did this with my 13L, it was well under half the original slot length, and I’m running 16 degrees static with a Mr. Gasket 925 spring kit installed, but only running 7 PSI currently. As the others said, the 1946 set-up for blow-through has been detailed in other posts, should be very easy for an EFI guy, make sure you block off all the vacuum ports, I epoxied mine. Plan on drilling your jet out to get a safe tune, and definitely plan on purchasing a wideband, don’t try without one, otherwise you will very likely cause damage. Make your carb hat as unrestrictive as possible, no smaller opening than your carb venturi, and avoid sharp inlet angles. I would also plan on an intercooler if you are going 10 PSI. I would even run a smaller turbo since you have a 200 and only shooting for 8-10 PSI, perhaps a T28 or Mitsubishi 16G. These I6 engines really do not rev very high and it is nice have near zero lag, it makes the engine much more efficient , even when your still running on the vacuum side of the gauge. Sorry these responses do not directly relate to your carb question, good luck have fun!
Click to expand...


Thanks for clarifying that, I myself remembered it was double late last night...
 
I think the .42 compressor might be on the small side.....same for the .48 exhaust.

I was running a 60/63 and had great results.

steping up to a 57 trim and 63 for the 250.
 
for guys with autos, might what did you do with the vacuum mod. on the auto tranz, i have seen some people run bleeds, or check valves, i was thinking maybe a auto tranz thunderbird turbocoupe might have one made for boost, but im not sure how there trannies are controlled.
also this would be my 1st boosted auto car also.
 
ryan11":1icfxds6 said:
for guys with autos, might what did you do with the vacuum mod. on the auto tranz, i have seen some people run bleeds, or check valves, i was thinking maybe a auto tranz thunderbird turbocoupe might have one made for boost, but im not sure how there trannies are controlled.
also this would be my 1st boosted auto car also.
Click to expand...
for guys that have boosted your stright6 what did you do or are your running a stick car?
 
Sometimes the modulators are uneffected. Try no provision first, otherwise include a check valve, or controlled bleed orifice.
 
351 celi":1equoev9 said:
Sometimes the modulators are uneffected. Try no provision first, otherwise include a check valve, or controlled bleed orifice.
Click to expand...
will do, do you happen to have a boosted 6 auto?
 
ryan11":3tytocyf said:
will do, do you happen to have a boosted 6 auto?
Click to expand...

I do, well did and the only problem I had was when I was cruising at 55-60 or so and would start to give it gas and the vacuum would drop it would want to downshift, and I wouldn't be giving it very much of a load. So if I was going up a small hill it would downshift when it didn't need to.
 
hasa68mustang":1suxh6y7 said:
ryan11":1suxh6y7 said:
will do, do you happen to have a boosted 6 auto?
Click to expand...

I do, well did and the only problem I had was when I was cruising at 55-60 or so and would start to give it gas and the vacuum would drop it would want to downshift, and I wouldn't be giving it very much of a load. So if I was going up a small hill it would downshift when it didn't need to.
Click to expand...

was that the only problem you ran into with the vac. mod seeing boost?

""""i do,well did"""" what happen to it, sold it, manual swap,ect.
also if you dont mind me asking what did your set-up consist of ?,carb,turbo size,
mac. or efi fuel pump,how much psi,stock motor,ect,ect..
 
ryan11":3esx0uxw said:
hasa68mustang":3esx0uxw said:
ryan11":3esx0uxw said:
will do, do you happen to have a boosted 6 auto?
Click to expand...

I do, well did and the only problem I had was when I was cruising at 55-60 or so and would start to give it gas and the vacuum would drop it would want to downshift, and I wouldn't be giving it very much of a load. So if I was going up a small hill it would downshift when it didn't need to.
Click to expand...

was that the only problem you ran into with the vac. mod seeing boost?

""""i do,well did"""" what happen to it, sold it, manual swap,ect.
also if you dont mind me asking what did your set-up consist of ?,carb,turbo size,
mac. or efi fuel pump,how much psi,stock motor,ect,ect..
Click to expand...

holley 2300 500cfm carb direct mounted, carter SBC fuel pump, mallory regulator, way too huge turbo TO4b with a s3 trim compressor (good sized) and an "O" trim turbine (1.0 ration turbine) don't get one that large :oops: ... lol. I ran 10 psi on the most recent setup, and 7 psi with a way undersized IHI turbo off a ford probe. Stock rebuilt motor, a small cam, springs and stuff. C4 with a shift kit. Under boost I always shifted it manually I don't remember if it would shift on its own under boost. Even before the turbo I shifted it manually because it always liked to shift early. with the stock carb it would shift around 4k rpms on its own. With the new carb and cam I would shift closer to 56-5800.

*edit* I missed the part when you said why I said I HAD the auto....
I broke it... lol I lost all forward gears, so drove home in reverse. then lost it in a sour deal with a tranny shop so I took the 6 cylinder out, parted it all out, and sold the motor, then put in a 4.6l mod motor and after getting it all in place someone posted up a free motor and tranny so I took it all back out and went back to the 6!
 
quote from hasa68mustang
7 psi with a way undersized IHI turbo off a ford probe. Stock rebuilt motor, a small cam, springs and stuff. C4 with a shift kit. Under boost I always shifted it manually I don't remember if it would shift on its own under boost. Even before the turbo I shifted it manually because it always liked to shift early. with the stock carb it would shift around 4k rpms on its own. With the new carb and cam I would shift closer to 56-5800.

*edit* I missed the part when you said why I said I HAD the auto....
I broke it... lol I lost all forward gears, so drove home in reverse. then lost it in a sour deal with a tranny shop so....

did you ever run the small ihi turbo set-up on a stock motor/stock everything?
what was the fuel set-up on a the small turbo set-up, ie boost ref. mech pump?,stock carb mods,ect??
 
ryan11":1zdzqr6j said:
quote from hasa68mustang
7 psi with a way undersized IHI turbo off a ford probe. Stock rebuilt motor, a small cam, springs and stuff. C4 with a shift kit. Under boost I always shifted it manually I don't remember if it would shift on its own under boost. Even before the turbo I shifted it manually because it always liked to shift early. with the stock carb it would shift around 4k rpms on its own. With the new carb and cam I would shift closer to 56-5800.

*edit* I missed the part when you said why I said I HAD the auto....
I broke it... lol I lost all forward gears, so drove home in reverse. then lost it in a sour deal with a tranny shop so....

did you ever run the small ihi turbo set-up on a stock motor/stock everything?
what was the fuel set-up on a the small turbo set-up, ie boost ref. mech pump?,stock carb mods,ect??
Click to expand...

I never ran it with the stock carb. I did run the stock mechanical pump with a boost reference though for the first setup. Doing it that way I had no problems, but I was worried about running out of fuel with more boost.
 
hasa68mustang":3a4zejs6 said:
ryan11":3a4zejs6 said:
quote from hasa68mustang
7 psi with a way undersized IHI turbo off a ford probe. Stock rebuilt motor, a small cam, springs and stuff. C4 with a shift kit. Under boost I always shifted it manually I don't remember if it would shift on its own under boost. Even before the turbo I shifted it manually because it always liked to shift early. with the stock carb it would shift around 4k rpms on its own. With the new carb and cam I would shift closer to 56-5800.

*edit* I missed the part when you said why I said I HAD the auto....
I broke it... lol I lost all forward gears, so drove home in reverse. then lost it in a sour deal with a tranny shop so....

did you ever run the small ihi turbo set-up on a stock motor/stock everything?
what was the fuel set-up on a the small turbo set-up, ie boost ref. mech pump?,stock carb mods,ect??
Click to expand...

I never ran it with the stock carb. I did run the stock mechanical pump with a boost reference though for the first setup. Doing it that way I had no problems, but I was worried about running out of fuel with more boost.
Click to expand...
cool, i think i will try to just boost ref. the stock 82 pump and go from there 1st.
 
havent been around in a while,but anyone have pics of were you taped your oil pan????
also my car came with that catted manifold,so what cars with years,, came with the non catted manifold?
 
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