Engine Setback

On a alcohol funny car, what's the common engine setback? (ie center of rear axle to motor plate)

 

Engine location Funnycar

I usually put the engine at 63" from the center of the rearend to the engine side of the rear motor plate.

Hope this helps

 

In my point of view, 63" is back to far. It might be ok if all your going to run is division tracks with so, so starting lines. Otherwise it needs to be 65 or better. 63 back is also going to make the car not so tuner friendly.

 

This dimension should always be referenced at crankshaft centerline continuing back through the differential pinion centerline. This dimension is taken from the axel shaft centerline to the engine side of the rear motorplate / midplate

Joe

 

You make a very good point about the setback being to much. I'll have to try putting the engine at 65" the next one I build to see if there is any difference.

Thanks

 

The hot setup would be to have a moveabel engine. for N/E set to 65 in for D/R setat 64in.

 

You could extend the length of the shoulder hoop tube at the first slip tube to accept the different engine positions but you have to weld in the rear motor mount tabs. Thats the only thing that would cause any problems. I don't think they would allow spacers behind the rear motor plate. The front would just clamp to the chassis in the various positions.

 

Also might have an issue of the body hitting the injector when you put it down, depending on the size of the opening...

 

Engine set back

If your body is very tight against the injector, ya that would be a problem, but if you were going between 64-66" I guess you could clearance for it. I don't know how that would affect the dynamics of the body. Plus it might not look that good if there is a big gap.

 

Might be able to make a plate or something like that so you could move the injector forward or back to fit through the hole in the body correctly....might take some work.

 

I've seen the same thing with no tech issues.

 

Bedtime story time again

OK kids, I'm old, but being of a curious nature, I try things.
In 1979, I built four F/C's with the rearend housing movable, with three positions, 122"-123"-125" wheelbase.
The thought was the whole car including driver moves.
Why? Because many respected "Tuners" (not chassis builders) when asked why they moved the motor back 1", will tell you "to pick up 100 lbs. on the rearend".
My barnyard logic says: if the motor goes back 1", you probably have to rebuild the car! If you put the front end on scales, then grab the headers and lift the motor 1" forward, it'll give you a real good idea of the change you're planning. A true fact: The legendary Leonard Abbott and I did exactly that + 7 more times, for a total of 8" farther out, guess what, the front end gained 90 lbs. TOTAL!!
Now here's the question kids, "How much lighter was the rearend"
Moral of the story is: balance = crankbolt, not distance!
And no I'm not retired yet, so I won't explain it, just the hint!
And for those wondering about the pain in the butt to build three position housing, it worked best all the way back, so I never bothered again. Of course the next car I built was Tim Grose's Skoal Bandit (first 5.40 Nitro F/C)(which lasted 10 years on the tour, with 4 bodies)but I went to long cars only for 20 years! I'm finally over it now.............(thanks Tim)

 

So then, the next question is, what's the distance from the ground to the crankbolt on most cars?

 

9 1/2 inch screw car