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Fri Oct 24, 2008 1:27 pm

Has anyone tried to put together a small cc, high revving, N/A, ACVW engine for drag racing just to see if it can be done successfully? If so, what were the results? Short stroke,64mm or less, 94mm cylinders to put the maximum amount of valve in the head. Stroker pistons to keep the engine and push rods as short as possible. High compression. Titanium rods,valves,keepers,pins. Intriques me. A sure sign of too much time on my hands!

Fri Oct 24, 2008 2:26 pm

Been done, but the oversquare RPM-monster has always been my favorite engine to build. I think turtle racer has a small engine similar to what you describe, he's a Frenchman if I remember correctly.
One thing- you mention 'keeping the engine and push rods as short as possible'; in a high-RPM engine, you want the opposite. Long rods are what you're after to slow the piston down.

http://www.thesamba.com/vw/forum/album_page.php?pic_id=311773

Fri Oct 24, 2008 2:40 pm

I did not mean connecting rods but rather push rods to keep flexing and weight to a minimum.

Fri Oct 24, 2008 2:52 pm

It was done all the time in the 70's & 80's in NHRA class racing. Gary Berg and others were turning 10,000 RPM in little engines.

It was also done in Midget circle track racing back when everybody was using VW engines.

Fri Oct 24, 2008 4:32 pm

Rocket Jim wrote: I did not mean connecting rods but rather push rods to keep flexing and weight to a minimum.

Pushrods are the least of your worries. They make steel p-rods that will take just about anything you can dish out. The biggest thing with high-RPM engines, is keeping the rod bearings oiled.

Fri Oct 24, 2008 6:59 pm

Where do you get a 64mm crank though?

Fri Oct 24, 2008 7:08 pm

buggpower wrote: Where do you get a 64mm crank though?

64mm is stock 1200cc 40 HP engine. DPR can counterweight them.

Fri Oct 24, 2008 8:07 pm

Here is a 1500cc engine that makes north of 180 HP..
http://www.youtube.com/watch?v=irnnTvn_iW0

It uses a cam smaller than most street cars and a set of 40X35.5 heads.. It is now twin plugged and has held the H/ GALT LSR record since 2003 and has broken the record 7 times.

I LOVE building high strung super small engines, but the challenges are abundant and not typically experienced here on the forums... This engine is 1/2" more narrow than a stock 1600 :-)