[AG]

Wow, that is a light race weight for a '70. My '65 had a race weight of 3758 lb with a TH400.

[SD455DJ]

Originally Posted by AG

Wow, that is a light race weight for a '70. My '65 had a race weight of 3758 lb with a TH400.

I was expecting about 3650 lbs. with a half tank of fuel with the spare tire in place. My brother Dan's '71 T-37 455HO weighs 3675 in the same configuration...TH400, 3.55 12-bolt rear, dual exhaust, no PS/PB, taxi cab interior...a stripper. It is what it is...

Dennis

[KSZR]

I did get a set of manifolds. Had to settle for 2.25", so sign of 2.5" available anywhere.

[SD455DJ]

You'll be fine with the 2.25" outlets. My stock 455HO did pretty good on the dyno (430 hp @ 4900 rpm/535 lb-ft @ 3500 rpm) with factory original RA manifolds with 2.0625"/2.125" outlets, so your larger outlet RA manifolds will work fine on your 400.

Dennis

[KSZR]

Originally Posted by SD455DJ

You'll be fine with the 2.25" outlets. My stock 455HO did pretty good on the dyno (430 hp @ 4900 rpm/535 lb-ft @ 3500 rpm) with factory original RA manifolds with 2.0625"/2.125" outlets, so your larger outlet RA manifolds will work fine on your 400.

Dennis

Cool! I'll have to measure mine.

The Parts Place had a few sets on eBay. Next morning they were sold out. Not sure you can find 2.25" now either.

[KSZR]

Originally Posted by SD455DJ

You'll be fine with the 2.25" outlets. My stock 455HO did pretty good on the dyno (430 hp @ 4900 rpm/535 lb-ft @ 3500 rpm) with factory original RA manifolds with 2.0625"/2.125" outlets, so your larger outlet RA manifolds will work fine on your 400.

Dennis

Did you have to grind down the lip of the head pipe that connects to the manifold? Mine is wider than the flange bolts.

My first exhaust job and want to do it correctly!

[SD455DJ]

Originally Posted by KSZR

Did you have to grind down the lip of the head pipe that connects to the manifold? Mine is wider than the flange bolts.

My first exhaust job and want to do it correctly!

Yes, just at the studs when using the factory RA manifolds or the non-oversized repop RA manifolds when mating the Pypes 2-1/2" head pipe flared end. The 2-1/2" oversized RA manifolds must have the studs set a bit further out to fit the 2-1/2" flared end of the head pipe as we never needed to grind clearance with them like we do with the factory and other non-oversized repops. We just used a rat-tail file to do that.

Dennis

[KSZR]

What is your method. to get such a good 60' time?

[SD455DJ]

Originally Posted by KSZR

What is your method. to get such a good 60' time?

Kent, We pump up the front tires to 45 lbs. to reduce rolling resistance and the rears to 35-40 lbs. for the most consistent tread patch from a small burnout at the tracks back-40 return roads, not to mention less rolling resistance down the track. I just power brake to 1200 rpm to reduce wheel spin (it will go up in smoke mashing the throttle off idle) by reducing convertor flash. The track is prepped with 'glue' and I try to find a fresh area that hasn't been used-up by cars ahead of me. With more work to the front suspension, the 60' times could be in the 1.85 area easily. A lot of racers at the Pure Stock Drags are in the low 1.80's/high 1.70's on repop belted tires.

Dennis