cuatrokoop

Some people have been using the complete 7A (NA 4v head) in home-brew 20vt motors. However, the cams are not fully optimized and there is more power to be had by just swapping the 7A cams for 3B cams, especially in the low-end. Their EGT's and A/F ratios have all been OK with the 7A cams, so they don't worry about it.

The 30v engine may have cams that are just "OK" enough for PES to not have new grinds? I've wondered about that myself. A lot of SC engines have NA cams in the aftermarket, and don't seem to have problems (look for 302, 350, 351 kits and you'll see what I mean, a few friends have blown small blocks that do not have SC-specific cams and make PLENTY of power). I think most of those kits are in the 4-6psi range, a few are running upwards of 10psi. All of those guys end up dyno-tuning with a WBO2, and run safe #'s.

cuatrokoop

BB has been working on cam profiles so that he can get a lower dynamic CR that is safe for a turbo application on the 7A engine (that way, no need to pull the block out and use parts from the NF/NG code 10v's to drop the CR).

cuatrokoop

You'd need a bleeder or pop-off, as those can be set to open at a certain pressure.

JörgenK

But I have never heard anyone with less then 350-400 real HP consider them.

JörgenK

...seen that used in a friends street driven (sort of) 1000hp naturally aspirated bigblock. I think that the cams was 326deg duration and he gets 6mpg. It's fuel injected with a good fuel injection system and the cruise mixture is verified to be lambda=1 with a commersial wideband o2 meter.

By judging his octane reqirement he bleed off 1-2CR points with the extreme cams.