Car Biz

iTrader: (1)

Yup. Ran the motors up to 3500 (advance was all in at 3200 though) set it @ 35 tighten up dist. done.

Scorpion Paul

The reason Im asking is because I just put a 355 together for my 21 and its a little flat on top. I have been conservative with timing due to the compression 9.7 I have also been battling with a weber 750 that wasnt very cooperative so I put a new Holley on it but had to winterize before I had a chance to run it. It has Dart heads with vortec chambers that are supposed to be more forgiving on higher compression due to the chamber design. I may try a single plane intake as well.

Pat Ousborne

My previous boat : 1988, 272 ls1 ,twin 250 prop HP alpha 1.5-1, 23' mirage props, GPS 59-60.0 mph4450 rpms. After adding the 350 mpi/300hp and counterrotating alphas 1.47-1 ran GPS 60.0 mph. We needed to cut 1' pitch out of props to get in rpm band and 60 mph. The counterrotation did nothing for top speed nor did the added power but easier backing up and noticeably more torque /acceleration especially when many aboard. Must need big blocks to get the torque for top end?My2 cents

Scorpion Paul

Thanks Pat It looks like im gonna have to get the hp/tq up to get the speed up there.