I bought a Hemi - Project Lit'lphant

[oldeskewltoy]

so back to the engine.....

Typically when you order new pistons, you plan for an overbore...




The cylinder liners are in very good condition, with no ridge at all, and only the very top of the bores no longer showing hone marks.... but the liners are likely a few ten thousandths different... so the intention at the shop now is to re-hone, and set all bores to within one ten thousandth (.0001"). With that final figure, I'll pass that along to Traum pistons so we can have the pistons made to the bores, instead of the other way around....

This was done about a week back... the results were all the liners were nominally under 87mm, so all the liners will be honed to 87.0008mm, or 3.4252"


and a bit more... note a small "squish" band around the entire piston... also note the valve reliefs are symmetrical, and yet the valves in the head are not....






Those domes are pretty shallow... estimated to be 13cc... (back in 2019)

OST Wrote:also note the valve reliefs are symmetrical, and yet the valves in the head are not....

This has everything to do with overall piston balance... if the pistons were to only have the intake relief, they would be much tougher to balance, BUT they would also be very expensive, as the engine would need 4 sets of 2 pistons. This is because the wrist pin is offset - you can see this in the side view of the piston. My new pistons will have a dome of 21cc, and the valve reliefs will be .060" deeper....




Well... word has come from Traum piston....

oldeskewltoy Wrote:Those domes are pretty shallow... estimated to be 13cc...

Actually... they were 10cc, so static CR on the 5V is(was) under 9:1....


Thank you Traum Piston - With their help, this is what my 5V will be running..... instead of 10cc, this piston has a 21cc dome




10.30-10.35:1, with slightly deeper (.060") valve pockets. Because the piston has an offset wrist pin, essentially that is 2 sets of 4.



And the last bit of news.... I spoke to the cam grinder this morning.. I have the specs on the stock 5V-EU cam.........



intake overall duration 240 ([email protected]"), and exhaust 247([email protected]") lobe lift is .240", and as I said before 110 centers.


more to come....