What type of tune up are you using
Mine
632 Alum block 18* Big Chief Heads, terminator with #1 pump, 39 nozzles, 110 return pill. Goes high 4.40’s in good air but slows to high 50’s in the heat.
08 American Dragster 1980 lbs race ready on the starting line.
Any others find it different to tune a 18* motor over a conventional headed motor??????
Any suggestions will be appreciated
On gas carb I have been 4.45 @ 155 and 7.10 @ 190 in the 1/4 mile. Only run 1/8th tho
Thx in advance

I don't have a 632 but I can tell you when I built the 582 and went with the 18* heads. I sized the pump up to a 1 and used 39 nozzle jets. The main stayed around the same as my conventional headed 555. Pill was in the mid to upper 80's range in the heat. Mind you I only had six passes on this deal before I wrecked but that was my starting point tune up wise. What kind of timing and egt you running?

This message has been edited. Last edited by: JP Miller,

I have a 572 conventional head BBC with a toilet and I have a 80a pump 40 nozzles with a 80 pill. Your way to lean that's why its slowing up. Keep putting fuel to you slow down. Put a 90 pill in it and reset barrel valve for that pill

Conventional heads are tuned different. I tune a 632 head hunter motor and it runs low 4.40’s in a dragster.

quote:

Originally posted by 00 DEAD ON:
Conventional heads are tuned different. I tune a 632 head hunter motor and it runs low 4.40’s in a dragster.

So Brian, what was your tune up with the conventional motor pump/timing/pill/injection system/ thnx

Terminator #1 pump 38 nozzles 100 return pill. 32* of timing. Shift @ 7400 stalls 6800 fallsback to 6900 after shift

quote:

Originally posted by 00 DEAD ON:
Terminator #1 pump 38 nozzles 100 return pill. 32* of timing. Shift @ 7400 stalls 6800 fallsback to 6900 after shift

Ok I have a 1/2 pump 37 nozzles 78 pill same timing shift @ 7200 stall about 6400 not sure of fall back just haven't gotten this engine maximized.

Take the engine and fuel system to Pat Donavan's dyno. It will be the best $600 you have spent.

Go to FIE(Fuel Injection Enterprise) web site he has a tune up calculator.You enter few numbers and it gives real good idea of where you should be on jet. You can change nozzle sizes and see what pressure you will have(well close) and what jet change needed to get you same fuel to motor. You could do all the math,but web site deal is lot easier. http://www.fuelinjectionent.com/

quote:

Originally posted by Brandon Davis:
Take the engine and fuel system to Pat Donavan's dyno. It will be the best $600 you have spent.

I agree with this but two things I would add.
1. Probably will not cost anywhere near that much to dyno.
2. Make sure you go to someone who knows how to work with and tune mechanical injection and is set up for it.

With mechanical injection you have the ability to to tune each cylinder different. But you need to know what each cylinder is doing. There is probably 8 engine dyno close to my house. I go three hours each way to dyno my motors because my guy specializes in mechanical injection. He knows what to look for and can get the tune up right in just a few pulls.

This is the reason I specifically called out Pat Donavan's dyno, just happens to be close to him as well.

quote:

Originally posted by 00 DEAD ON:
Terminator #1 pump 38 nozzles 100 return pill. 32* of timing. Shift @ 7400 stalls 6800 fallsback to 6900 after shift

what does your car weigh with you in it?

There is no reason to need to bring this type of motor to a so call MFI specialist. If the dyno operator doesn't know how to tune one of these then they can't do carbs either.

MFI is the simplest system out there.

And BTW most think these deals have a dry intake (No fuel), far from that! So tuning the motor by changing nozzles on a static dyno is not the same as what goes on racing on a track in the dynamic world.

When I ran my Duke stuff on my 588 injected we were 40/78ish +or- a few I think you are quite lean.

quote:

Originally posted by Bob Payton:
When I ran my Duke stuff on my 588 injected we were 40/78ish +or- a few I think you are quite lean.

Bob Was that with a #1 pump?????

That was a twin gear rons pump. Do you guys have an 02 on that thing?

No we do not Bob. I bet that Twin Gear pump was a 0 1/2 pump. I have tried smaller pills but then it’s way to fat.

Call James Monroe he can tell you where you need to be with it

# 1 Black pump 39 noz 86 pill Gray Barrel valve seems to work good on my 565 con head motor

Not the fastest but an 18 degree engine on a enderel single “toilet”; so here is my “story”.

2004 race tech dragster at 1975 pounds after a run on Norwalk scales. Dart iron block, dart 18 degree heads, 14:1 compression, Q16 pistons, dart manifold (all out of the box with no porting), 5” toilet, 0.5 pump, 34 nozzles, 100 main pill, no high speed leanout., torque converter brake stalls at 6000, shift at 7200 fall back is right around 6200.

Average day performance is 7.60’s and 4.67 in the eight. ¼ mile trap speed is 179; 144 at the 1/8th

bob