I've got my heads to the machine shop and I'm just getting them milled a bit, blown head gasket. I am going to install 1.6 RR and heads ported just a bit to clean them up. Stock cam as well. With this set up do I want to retard cam timing from stock to get more middle top end or leave it where it's at? Any info or help appreciated. Also, should I spend the extra $$ to get to more adjustable ie 2* increments timing chain set or???

 

This has a lot to do with where you want your power range. I noticed in your picture. You were autocrossing. If your focus is short runs with fast
acceleration uo to 3000-4500 rpm's Advance it.
If you are drag racing and want all the rpm's you can get , a
slight retard may help. I have never found this to help in my own e-t times.

 

Thanks Mike. :cheers: Anybody else?

 

I'm curious as well. :cheers:

 

Unless anyone can tell me a reason otherwise, I'm going to leave it stock. I don't want to lose anything at the upper rpm's. I wish some folks who have played w/ this would chime in.

 

me too :iagree:

 

Hey Rob, if you gotta have it torn down, this is the time of year to do it up there :seeya

I don't have any experience with that particular cam, but I do know the general rule is to advance the cam if you want more lower end, and vice versa for upper RPMs. Assuming, that is, the cam was ground zero or straight up to begin with. Check over in the engine mods section though, those guys are all over this kind of stuff. Hope it all goes well for you on this project Bud!!!:cheers:

 

Rob, the guys before are right about advancing or retarding based on what you're looking for. BUT, here's where you have me confused. You say in your sig you're going to run BSP next year. You MUST have stock cam timing in BSP. Hell a couple of years ago the HS national champion lost a protest in which his ignition timing was supposedly changed to help performance....when they checked it, it was actually advanced too much (thus slower) because the distributor bearings were worn out, but they DQ'd him anyway. If you're running BSP at any national level events where you might get protested, I'd leave it alone. The L98 doesn't breathe worth anything at high rpms more because of the intake than the weak cam. Of course, you *can* change manifolds in BSP. But, if you're not changing the intake, and not concerned about protests, if anything I'd advance it to give you more low end horsepower. You spend so little time (relatively) in the higher rpms in auto-x, it doesn't make much sense to give up the low end power.

BTW, I'm curious as my engine is a mild BSP engine (basically just exhaust...no intake mods...last rebuild took tolerances to max of BSP rules, except in bore, it's only a 0.010 over...it's an '87)...what are your RWP numbers? I'm getting 228 RWHP and 336 RWTQ.

 

I have never had the car on a dyno, so I honestly don't know. I have decided to build my car to suit me and I'm not a competitive driver even locally at BSP, so I threw the rule book away. I'll run it time only and enjoy the 99% of the time it's on the street much more. I guess it's time to ammend my sig. :seeya

 

Rob, I think you will benefit from raising the peak RPM of your power curve, even on the street. With ported 113s and a little more lift & duration in your stock cam, you should have plenty of low end torque.

You've got mail with some cam (though not stock) timing variations results.