Wrong direction on stroke

[Little Mouse]

Some like to use steel rods others like to use aluminum, pankle rods were mentioned. Forgot to mention block is compacted graphite. Main caps 8620 steel. They feel billet aluminum blocks not cast aluminium would give them as much not flexing as the iron block, but NHRA wont let them use it. Kind of laughable if that's to save money in a corporate sponsored new world they have to live in.

[dwilliams]

Herb Adams destroked a Pontiac 400 to 303 CID to meet SCCA class limits in the late '60s. It used a 2.84 inch Moldex crank and 7.08 inch Carrillo rods.

[midnightbluS10]

Been reading about the new DRCE4 pro stock block and what there doing in pro stock. Ya the mains are the old 409 size 2.5, rod pins are Honda size 1.888. Cam can be from 70 to 80 mm. The 80 mm is 16 mm bigger the mains on the crankshaft, has 9 jurnals supporting it, compression rings are either stainless steel or carbon steel .021 with a titanium nitrate coating, oil ring 2.00 mm. Oil viscosity they use W02. Deck height as block comes 8.90 can be cut up to .300 lower. Crankshaft is 50lbs and I forget the mandated rule on the piston, pin and rod. Think the piston was 430 grams, pin 130 grams. Original bbc took somewhere in the 25 to 35 lb range to turn the rotating assembly. They only need an inch pound tq wrench to check theres. They have some special tool to check cylinders for roundness to 1 micron. All of GMs DRCE4 blocks and there nascar block are made by a company over in england or there more proper, united kingdom. Lol

If you want to do some reading, there's a 'Pro Stock Tech" thread in the NA forum at yellowbullet.com that's a known hangout for a few pro stockers. Engine builder Nick Ferri, what's his name from Madcap that goes by 'goneracin' , and one or 2 others. They regularly talk about pro stock tech there. Lots of good info in the 300+ pages of replies

https://www.yellowbullet.com/threads/pr ... 0/page-300

And afaik, RMS was the first to do that crank in that block. They were running 362ci big blocks in pro stock before anyone was running that combo anywhere afaik.

[Little Mouse]

So I'm curious how did they do it, make spacers for the mains and how is that even done.

[tenxal]

.....make spacers for the mains and how is that even done.

It's no different than putting a small journal crank in a big journal (non 400) SBC block. Most use an old set of bearings and hone them to fit the new small journal bearings.

Warren Johnson did much of the early 348 crank/BBC Pro Stock engine development, along with RMS. These engines were also very popular in the Comp and Modified classes.