Crankshaft centerline height

DRR Trophy

posted

Front clipping my car and thinking about lowering the engine in the car. What is a good spot to be for a 2400lb race ready car 50/50 weight bias? 632 1125hp and have the option of 1.80 or 1.65 glide, will be 4.56-4.86 rear gear 33x15 or 32x16 slick. Would it be different if running a 32x14 radial?
Thanks in advance for any input.

Posts: 481 | Location: Indiana | Registered: January 20, 2020

Larry Woodfin

DRR Pro

posted

Because you are upgrading to a powerful engine and your car is relatively lightweight, your question is valid and important. I suggest finding other cars with similar performance and weight. Plus, maybe talk with chassis builders. I think good research by experienced builders is vital. Another, I have enjoyed a good relationship with Dave Connolley at Competitive Suspensions and Tod Bevis at Modern Race Cars.

Larry Woodfin

Posts: 2086 | Location: Longview TX | Registered: March 12, 2004

Ignored post by Larry Woodfin posted

Larry Woodfin

DRR Pro

posted

Another thing, Mr. Inferno: in my experience, a 1.80 Powerglide works very well across a wide range of conditions and packages. I think you will be leaving ET on the table with a lesser ratio.

Larry Woodfin

Posts: 2086 | Location: Longview TX | Registered: March 12, 2004

Ignored post by Larry Woodfin posted

Rodney Pryor

DRR Trophy

posted

My 'fast' bracket car was a lot more efficient with 4.56 x 1.69 combination compared to 4.29 x 1.80 - the starting line ratio was basically the same, but the converter slippage out the back improved greatly - this was going 480 on HP and 430 - 445 on nitrous

Posts: 145 | Location: Richmond, VA | Registered: December 07, 2002

Ignored post by Rodney Pryor posted

DRR Trophy

posted

I'm not changing engines. I will still be running the 632 that was in it before. I have ran both the transmissions in the car. The 60'was about .02 quicker with the 1.80 but pulled better in the middle with the 1.65. Overall the 1.80 was maybe .01 quicker. I ran them both with a 4.86 gear.
With that said I was pulling some timing with the 1.80 that could probably put back in after getting the ssupension tuned in.

Posts: 481 | Location: Indiana | Registered: January 20, 2020

Ignored post by inferno camaro posted

Jonesz

DRR Sportsman

posted

quote:
Originally posted by inferno camaro:
I'm not changing engines. I will still be running the 632 that was in it before. I have ran both the transmissions in the car. The 60'was about .02 quicker with the 1.80 but pulled better in the middle with the 1.65. Overall the 1.80 was maybe .01 quicker. I ran them both with a 4.86 gear.
With that said I was pulling some timing with the 1.80 that could probably put back in after getting the ssupension tuned in.

1.80/4.86 is WAY over geared for 632 bracket car going 5.0's.

Posts: 138 | Location: Over here | Registered: November 28, 2007

Ignored post by Jonesz posted

Rodney Pryor

DRR Trophy

posted

quote:
Originally posted by Jonesz:
quote:
Originally posted by inferno camaro:
I'm not changing engines. I will still be running the 632 that was in it before. I have ran both the transmissions in the car. The 60'was about .02 quicker with the 1.80 but pulled better in the middle with the 1.65. Overall the 1.80 was maybe .01 quicker. I ran them both with a 4.86 gear.
With that said I was pulling some timing with the 1.80 that could probably put back in after getting the ssupension tuned in.

1.80/4.86 is WAY over geared for 632 bracket car going 5.0's.

I agree.

Posts: 145 | Location: Richmond, VA | Registered: December 07, 2002

Ignored post by Rodney Pryor posted

DRR Trophy

posted

Also have ran 4.57 and 4.29 gear and the 4.57 was basically no change in ET but the 4.29 slowed down roughly .07 and 2 mph. This how I ended up on the 4.86 gear with 1.65 glide.

This message has been edited. Last edited by: inferno camaro,

Posts: 481 | Location: Indiana | Registered: January 20, 2020

Ignored post by inferno camaro posted

imakehp

DRR Top Comp

posted

quote:
Originally posted by Jonesz:
quote:
Originally posted by inferno camaro:
I'm not changing engines. I will still be running the 632 that was in it before. I have ran both the transmissions in the car. The 60'was about .02 quicker with the 1.80 but pulled better in the middle with the 1.65. Overall the 1.80 was maybe .01 quicker. I ran them both with a 4.86 gear.
With that said I was pulling some timing with the 1.80 that could probably put back in after getting the ssupension tuned in.

1.80/4.86 is WAY over geared for 632 bracket car going 5.0's.

Maybe he's running 1/8th mile?

.
Dave

F J B

Posts: 4674 | Location: Earth | Registered: February 08, 2006

Ignored post by imakehp posted

Jonesz

DRR Sportsman

posted

quote:
Originally posted by imakehp:
quote:
Originally posted by Jonesz:
quote:
Originally posted by inferno camaro:
I'm not changing engines. I will still be running the 632 that was in it before. I have ran both the transmissions in the car. The 60'was about .02 quicker with the 1.80 but pulled better in the middle with the 1.65. Overall the 1.80 was maybe .01 quicker. I ran them both with a 4.86 gear.
With that said I was pulling some timing with the 1.80 that could probably put back in after getting the ssupension tuned in.

1.80/4.86 is WAY over geared for 632 bracket car going 5.0's.

Maybe he's running 1/8th mile?

Which has zero to do with having way to much starting line ratio, and alot to do with the wheel stand causing a complete rebuild.

Posts: 138 | Location: Over here | Registered: November 28, 2007

Ignored post by Jonesz posted

DRR Trophy

posted

When it wheelied, it had the 4.56 and 1.65 low gear glide in it.

Posts: 481 | Location: Indiana | Registered: January 20, 2020

Ignored post by inferno camaro posted