Any demo derby guys here? GM 4.1 question...

[85Bowtie]

I picked up an '84 Cadillac with the 4.1 motor, and I mean I just picked it up....haven't even had time to look through it thoroughly other than a quick check to make sure it ran and drove.

It looks to have a throttle body on it, and I'm assuming an electric fuel pump as well.

The class I run is stock, no mods to the motors except maybe a throttle body to factory style carb swap.

Does anyone know how you run these cars with throttle bodies and electric fuel pumps? What I mean is, what do you do for a fuel pump when you eliminate the gas tank? I use a 5 gallon boat tank strapped to the back seat location which works great with a mechanical fuel pump.

So I guess my questions are:

1) How do you deal with losing the electric fuel pump when removing the gas tank?

2) Do you run into any problems in your derbies using a throttle body?

3) Is there a carb that will bolt to the intake in place of the throttle body?

4) If replacing the TB with a carb, what do you use for a fuel pump...inline electric? How would you mount it safely?

5) Are 4.1's even good motors for derbies?

6) Is there a "kill switch" for the fuel pump in the event the car is in an accident and how would I eliminate it to run the car in the derby?

Thanks

[Benelli]

Originally Posted by 85Bowtie

I picked up an '84 Cadillac with the 4.1 motor, and I mean I just picked it up....haven't even had time to look through it thoroughly other than a quick check to make sure it ran and drove.

It looks to have a throttle body on it, and I'm assuming an electric fuel pump as well.

The class I run is stock, no mods to the motors except maybe a throttle body to factory style carb swap.

Does anyone know how you run these cars with throttle bodies and electric fuel pumps? What I mean is, what do you do for a fuel pump when you eliminate the gas tank? I use a 5 gallon boat tank strapped to the back seat location which works great with a mechanical fuel pump.

So I guess my questions are:

1) How do you deal with losing the electric fuel pump when removing the gas tank?

2) Do you run into any problems in your derbies using a throttle body?

3) Is there a carb that will bolt to the intake in place of the throttle body?

4) If replacing the TB with a carb, what do you use for a fuel pump...inline electric? How would you mount it safely?

5) Are 4.1's even good motors for derbies?

6) Is there a "kill switch" for the fuel pump in the event the car is in an accident and how would I eliminate it to run the car in the derby?

Thanks

1 - The problem with running EFI is the high fuel pressure they take, but throttle body is not as bad as direct injection. (It takes roughly 12-15psi)

2 - Never ran TBI or know someone well enough who ran one.

3. There might be an adapter, however with a Caddy motor it might not be available.

4. Yes, inline electric. The best thing you can do is mount it so that you can see it. If you bolt it down correctly somewhere out of the way of the sides of the car you Should be ok.

5. Never heard of/seen one ran.

6. Inertia switch, I couldn't say where it is or how to bypass it.

www.wecrash.com is an excellent resource.

Good luck.

[68C15]

I think I can solve all your questions by adressing #5. NO, a 4100 will over heat very easy. VERY easy. plus they are low on power.
find a 472, 500, or even a 425 and swap it in. then just hope the 2004R tranny will hold up.

[Benelli]

Originally Posted by 68C15

I think I can solve all your questions by adressing #5. NO, a 4100 will over heat very easy. VERY easy. plus they are low on power.
find a 472, 500, or even a 425 and swap it in. then just hope the 2004R tranny will hold up.

He might as well get a different car then, a lot of people don't want to let go of BB Caddy motors for cheap.

[85Bowtie]

I had a 425 in a '79. Wish I would have yanked it out before I crushed hte car but it was so wrecked from the derby it would have been a PITA.

Looks like I'm either going to do a 307 or Olds 350 swap. I didn't know that 4.1 was that big of a POS.

Will a 307 swap right in as far as wiring, transmission linkage etc? I know dimensionally it fits, but is it a straight forward swap?

Thanks again