cam choice- 236 or 242

[TurboTR]

This is for my 274" S2 shortblock with GN1R heads. Solid roller. Street strip weekend warrior type application. The engine needs to run strong between about 62-6300 and 71-7200 rpm down the track. I don't want to go higher for longevity's sake. Also trying to decide on spreading the lobe separation out some. That would be good for reducing overlap, no question but also in getting the exh valve open sooner, which cylinder pressure testing seems to indicate would be a good idea. Anyone have any experience with spreading the lobe sep a little vs conventional (like say 114 vs 110)? Wondering if a 236 would get the job done in that rev range, or is the 242 better suited. Also has to run well on the street.

Right now it has a 224/224/110, installed several degrees advanced. TH400 with about 3600-3800 stall. Runs great down low right now but needs alot more past about 6000. Any input welcome! TIA!

TurboTR

 

[John Wilde]

I would go with the 242. You may need to loosen the converter up for it to spool for you. We have run Duttweiler spec cams in the 270 @ .50 range on stage 2 headed motors. One car was street driven every now and then and reved to about 7000 to 7500.

 

[10SV6]

I called Duttweiler's a few months back. He said to stay with the 236/236. If I wanted to spin more rev's than you were talking about, use a larger turbo, 76 on now. Comp with their lobe profiles weren't able to spread the LSA to 114 on the blanks they have. I ended up having them do a 236/236, 110 lsa, I don't rememer the lifts right now, using an extreme energy lobe. Quicker ramp rate than the Precision. Lash if I remember right was .014/.016.

Still not in the car yet.