Is it a cost saving? Is it tradition from the old days? Are they related to Nascar blocks in any way? Do they start life as a stock block from a manufacturer? Why don't they use a sprint car aluminum 410 in SC? If they did, could you swap the engines between a sprint car and an SC car?

I'm just uninformed and curious.

Discuss.

Is it a cost saving?
Yes.
Dart Little M lightweight iron block, $3,535.95
Brodix Aluminum Block, $5,272.95
Prices from www.summitracing.com

Tradition?
Don't know.

Are they related to Nascar blocks in any way?
Don't know diddley about Nascar

Do they start life as a stock block from a manufacturer?
They can, but the Dart block is more cost effective & is of more consistant quality.

Why don't they use a sprint car aluminum 410 in SC?
Speeds are about as fast as SC cars can "safely" crash with the 355's

If they did, could you swap the engines between a sprint car and an SC car?
Probably, but I think I would want to change the camshaft because of the track length & the car weight.

WE HAD 350 STEEL BLOCKS IN USAC SPRINTS AND CHAMP DIRT CARS FOR YEARS! THEN THE LEADERS OF USAC SAID LETS SCREW THINGS UP AND PUT A BIGGER ENGINE IN A SPRINT CAR!!!!!!!!!!!! FOR OVER 60 YEARS A SPINT CAR OR BIG CAR HAD A SMALLER ENGINE THEN A CHAMP CAR! PLUS A 410 WOULD NOT RUN 100MILE RACES WITHOUT STOPING FOR FUEL AND TIRES AND SPEND MORE MONEY!!!!!!!:checkered::headbang

The Toyota Silver Crown motor is based on the motor from the Camping World Truck Series.

A couple of issues that might arise from running 410 motors in Silver Crown cars are straightaway speed and reliability.

An interesting fact: One of the options to "save" the Silver Crown series before the new car option was on the table, was to change the Sprint Car motor rules to Silver Crown motor rules, so owners could run the same motor in both divisions.

4 bolt used steel block in wrecking yard $75!

To go along with SUPERDUKE on this is the number of 4 bolt steel blocks out there is huge. Also a 410 would never make 100 miles on 1 tank of fuel. A silvercrown motor on pavement should be able to run with a 410 sprint motor. Not sure about dirt.

Good luck on finding a GOOD steel block these days in a junkyard. They should keep the 355 cid rule but allow aluminum blocks. If a steel block cracks your ****** but if u hurt a aluminum block... u can fix em for the most part. I know the aluminum block issue has been talked about in some of the USAC meetings but they keep shooting it down.

HOW MANY YOU WANT? WHY SPEND MORE MONEY TO WIN $9000:checkered::kookoo

But then you have to add all the Machine Shop costs to make a junkyard block as race ready as a new Dart block already is. Also, the Dart block has thicker cylinder walls & a thicker deck.

As far as reliability goes, we are getting 20+ races out of a 410 and my math puts that at a little over 200 miles.

As to fuel, I am getting a little better than 2.3 miles per gallon out of the sprint motor. With a 65 gallon SC tank I could go at least 125 miles.

As to $75 junkyard blocks, yes you can get plenty at that price but the last time I asked Earl Gaerte he said you have to clean and sonic test 10 to find one that can be used for racing due to the manufacturing tolerances. Then you have to machine the block to racing specs and by the time you are done you might as well have purchased the Dart block. If you throw a rod in the Steel block you get to invest another $3,500 in a new steel block and you now have more in the motor than if you had bought an aluminum block.

As far as speed, yes the sprint car engines do have more power but it is not as great as some might think. There are SC engines pushing 800hp right now! Couple that with the fact that Sprint/SC cars are not very clean aerodynamically and you won’t see a tremendous increase in speeds.

If this was the direction USAC wanted to take, you could phase it in with a 5 year period where you could run an aluminum block 360 if you bolt 60 pounds to your firewall or 410 and run injector restrictors. The 60 pound weight option was successful in the late 80’s to convert the sprint cars without antiquating the existing engines overnight and they are experimenting with the restrictors in USAC right now on the west coast.

Just my $.02.

Rob Hoffman