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Discussion Starter · #1 ·
What street carb would you recommend for a fairly angry 383 Stroker with a 600 lift cam and about 11:1 compression? Currently it has a racing carb on it that is about 850cfm with mechanical secondaries. In this set up it like to load up and foul out plugs at idle or part cruising. Im looking to tame the car down a bit for the street, not a daily driver but a weekend warrior. Im looking for something I can install and drive out of the box with the minor adjustments..

Recommendations and why?
 

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the 850 you have is probably the correct carb.The cam you have is not what everybody likes.I have a cam like that and use a bigger carb and it behaves fine.It takes awhile to learn how to tune it.
 

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Just below 9 psi. but the car has a nascar style fuel cell with 2 fuel pumps one on each side.
Edelbrocks and Quadrajets will tolerate up to around 6 psi, but will run best with 5 to 5 1/2 psi fuel pressure. Holleys will tolerate up to around 7 psi, but will run best at 5 to 5 1/2 psi fuel pressure.

Fuel flow into the carburetor bowl is controlled by a needle and seat arrangement. Excessive fuel pressure will unload the needle and seat and blow raw fuel into the intake manifold, creating the problems you posted.

Most of you younguns have grown up with EFI, where you can make more horsepower with more fuel pressure. Carburetors are a completely different ballgame. Get your fuel pressure down to 5 to 5 1/2 psi before you do anything else.
 

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Discussion Starter · #8 ·
You do not need a new carb and you cannot buy a magic carb that will run perfect out of the box.
You need to dial in the one you got ..The problem is more if a ignition set up problem than the
carb.

What cam?

Distributor
Timing curve, timing at idle
carb model number pri jets sec jets power valve.
Fill in the blanks.
Can show you how to set it all up to run clean, not load up and not foul plugs.

Its a matter of set up details not a i need a new carb problem.
The car is not too big.
Well I just got the car and had it ideling for a while and the previous owner told me it likes to foul out plugs. The car was set up as a full road race car.I cant recall all the detailed specifics and havent taken the carb apart to see the jetting.
Carb: Dillman Racing Carb
plugs: NGK V power 7 R5671A-7
Ignition: MSD 6AL
Coil:MSD Blaster 2
Cam: Lunati #50199LUN
I have the reciepts for the engine and spoke to the engine builder. Was told it was a 383 punched out to a 389 and about 11.0:1 compression
Rear gears are :308's
Tranny is a Jerico 4 speed

Does this help?
 

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Discussion Starter · #9 ·
Edelbrocks and Quadrajets will tolerate up to around 6 psi, but will run best with 5 to 5 1/2 psi fuel pressure. Holleys will tolerate up to around 7 psi, but will run best at 5 to 5 1/2 psi fuel pressure.

Fuel flow into the carburetor bowl is controlled by a needle and seat arrangement. Excessive fuel pressure will unload the needle and seat and blow raw fuel into the intake manifold, creating the problems you posted.

Most of you younguns have grown up with EFI, where you can make more horsepower with more fuel pressure. Carburetors are a completely different ballgame. Get your fuel pressure down to 5 to 5 1/2 psi before you do anything else.
Yes, this carb is a "dillman racing carb" Never heard of them..Im guessing some sort of aftermarket shop carb. I had to clean out the needle and seats cause the car sat for 8 months and was gunked up. Keep in mind i just go the car and have no idea what the timing is set at yet, Im just having start up and runing issues at this point.
 

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Discussion Starter · #10 ·
Same guy back again looking for that magic carb.
You didn't take my advice last time.
Your last radical motor needed a specific setup which explained to you in detail
but you don;t ant to listen. This engine is going to be no different.

When you set it up right it will run right and drive fine on the street.
reread the last go around and do it this time.
The last carb I had Im convinced was screwed up and am sticking to that story. Either it would idle right and bog during acceleration, or accelerate right and load up at idle.
 

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it looks like you have a race car bolted to your race carb and race engine.what are you trying to accomplish? are you racing it? curious how you like the jerico? I considered it but with out a speedo I went with a street friendly tko.
that carb is obviously a holley thats been modified
 

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Discussion Starter · #14 ·
it looks like you have a race car bolted to your race carb and race engine.what are you trying to accomplish? are you racing it? curious how you like the jerico? I considered it but with out a speedo I went with a street friendly tko.
that carb is obviously a holley thats been modified
Im looking to tame the car down so I can take the car to local cruise nights and not have to change the plugs after driving there.I havent gotten the car out on the road yet, just picked it up and having fouling issues, plus the massive hurricane that were getting hit with up here has put a damper on my day.
 

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Im looking to tame the car down so I can take the car to local cruise nights and not have to change the plugs after driving there.I havent gotten the car out on the road yet, just picked it up and having fouling issues, plus the massive hurricane that were getting hit with up here has put a damper on my day.
Forget about less cam if that's what you have in mind. If your SCR truly is 11.00:1, then the cam that's in there now is perfectly matched to the SCR, providing a DCR of 8.53:1 with an intake closing point of 54 degrees after bottom dead center @0.050" tappet lift. Less cam will raise the DCR and render the motor inoperable on pump gas due to detonation. My best advice, build another, milder motor for cruising. Or cruise in another car, a stocker.
 

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From what I can read your cam is very close to what I have in my engine. It will be expensive to drive on the street,no doubt.Not sure what intake that is? dart?My engine makes peak power at 6500 rpm,yours will likely make peak at 7500 rpm.
your intake and carb likely work best from 3500 up,so launching the car will be a pain.Hope your 1st geat is lower.I bet that carb flows over 1,000 cfm.
I think you will need about 22 degrees initial timing and all in by 2500.about 35 degrees total.It should idle at 950 to 1000 rpm.no idea about jetting because the carb will flow more than the 850 it started with.
You will at some time need to book some time on a "mustang" chasis dyno( or another dyno that can load the engine and powertrain) dont bother with an inertia dyno.
you will need a few booster venturis,jets,air bleeds etc when you tune it. other than 0 to 15 mph it should drive fine.If you road race it then its fine. Gearing will be sugguested to you by someone and this time I will probably agree. I went to 3.50 gears but I also have o/drive so I didnt lose anything. use a speed calculator and 2500 rpm as a cruise rpm for that engine.
hard to drive race cars on the street
 

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Discussion Starter · #17 ·
Forget about less cam if that's what you have in mind. If your SCR truly is 11.00:1, then the cam that's in there now is perfectly matched to the SCR, providing a DCR of 8.53:1 with an intake closing point of 54 degrees after bottom dead center @0.050" tappet lift. Less cam will raise the DCR and render the motor inoperable on pump gas due to detonation. My best advice, build another, milder motor for cruising.
Can I cruise this motor with some carb and timing adjustment? Im ok with a slightly radical motor as I only go 5-10 miles to local car shows and not really looking to go stock..I guess I want to be able to drive this car to the track a few miles away and drive ti to local meets. Or do you think this motor is too ridiculously radical for that? I mean i have seen guys cruising big ***** blown big blocks to the meets..
 

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If it was mine I'd swap out the single plane for an air gap style dual plane intake. You'll still need to change the plugs and tune the carb, but the intake swap will really help with the idle and around town stuff.
 

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You can cruise a Fuel Funny Car if you're willing to put up with its idosyncrasies. As far as a blower motor, the blower will tame down a radical cam and make the car driveable on the street. It appears to me that you have ignored the advice of one of the sharpest tuners on this board, F-BIRD'88. Back up and re-group.
 
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