QUESTION 1

Dear Tim,

First let me congratulate DRO on providing us want-to-be drag racers with such a great web site to ask dumb questions. You have probably saved more lives and caused more divorces than you will ever know.

My question: is it advisable to run front and rear motor plates on a street driven car? I am building a '62 Nova, 383 stroker, modified 700R4, 9 inch with 3.70 gears, and will see occasional dragstrip use. Is there a way to eliminate engine vibration and is it necessary to use a transmission mount when using a rear engine mount? I am concerned about oil pan, steering and header clearance.

Thank you for your reply.

John Johnson
Millville CA

John Johnson,

A front motor plate will take some of the load off of the stock rubber engine mounts and eliminate some of the vibration. The mid plate installation in that type of a car is a real headache and doesn't leave enough room for the headers so I would stay away from it. Your car should be just fine with the front motor plate only.

Good luck,

Tim

QUESTION 2

Tim,

I feel certain you can get me headed in the right direction. I need some good resources for chassis alignment. We run a 1966 Chevelle Stick Car. We have in the last year gone from 7.10 - 7.30 range to low 6's by upgrading axles, horsepower, and replacing the Gnash with a Jaycee. We are currently number 5 in the points race. As the car has picked up in ET we have developed some chassis issues. We run a ladder bar coil over setup. We consistently have 60' times around 1.35 - 1.40 depending on the track. Our car weighs 2,995 with driver and our small block is pushing around 750 HP. We leave the line at 8,100 RPM. Following is my problem

The car leaves very straight and consistent but is doglegging (crabbing) on the top end. It is not noticed until third gear - just beyond the 330' mark. Very noticeable on the top end just before the light at 660'. How can I best go about determining how much out the rear end is (you can see by eye) and then how do you suggest correcting the issue. It is my belief that our stability when shifting to third is being affected by the chassis - on a greasy track the car is very squirrelly on the second half of the track.

Any advice or resources would be appreciated. Thanks.

John Turbyfill

John,

A real quick check for rear end alignment is to stretch a string across the bulge of the rear tire all the way to the front spindle. To do this set the air pressure in the rear tires to 15 lbs. At the center of the rear tire bulge from front to back stretch a string so that it is tight and just touching the bulge at the front of the rear tire. Stretch the string all the way forward to the center of the front axle spindle. Use a tape measure and record the distance from the string to the spindle. Repeat on the other side of the car. If the alignment of the rear end is off it will show up in these numbers. Adjust the rod ends in the ladder bars to align the rear correctly. Double check all your measurements before you try the car out.

Tim

It's been a while since we had a chassis Q&A, but we now have veteran chassis builder and Pro Mod racer Tim McAmis to give you the benefit of his years of experience. So keep those questions coming to chassis@racingnetsource.com and look for the answers right here in Check Out This Chassis!

(more stories)