Shift point for XR310?

[scott s]

 First, let me start off by saying that I DON'T have a full dyno chart for this engine nor do I plan on getting to the track anytime soon....that said....

 When I had KSR rebuild the 2276 in my '63 I put in a lower RPM chip and lowered my shiftlight shift point in an effort to not abuse the engine and over-rev it like I did before. (The over-rev that hurt it was unintentional and happened because of a shift light malfunction and my stupidity...doh!)
 However, even when I was shifting at ~6800, the engine was still pulling HARD. I now have DRD's hi-rev springs (supposedly good for 8K), the XR-310 cam and Jeff Denham 044's. With the shift light set at ~6450 and a 6600rpm pill, it feels like the engine is nowhere NEAR done.
 I'm guessing it's making 190HP. It made 175HP at only 5200rpm.
 The XR-310 is very similar to a K10. How much higher can I SAFELY rev it?

 Some specs:
 XR-310 cam by SLR, 268* @ .050, 310* duration, .534" lift with my SCAT 1.36 rockers, .392" @ the cam
 044's by Denham with 44x37.5 valves, good springs and correct geometry
 Berg 5-speed: 3.88R&P, 4.11, 2.47, 1.78, 1.31, 0.89
 205/65/15 Yokohama's on the rear

 With the close gears, it gets to the shift point pretty quickly but is still pulling like a freight train. Think I should put in a 6800rpm pill? A 7000 pill?

[Clinton DdK]

Your set up is not that far off of what I was running. I had a SLR XR320. This cam would easily pull to 8000rpms. I shifted at 7500 and had a 8000 chip in it. I would try shifting at 7200 and put a 8000 chip in. Not to steel this thread put I had Steve grind my cam and lifters. The lifters were the good old Scat lube a lobe that had pitted before Steve had grinded them. I just pulled this cam out of my engine and it looked great, lifters were all nice and shiny with no pitting whats so ever. This engine had seen two and a half hard seasons and plenty of street time.Good Luck

[scott s]

 Thanks for the reply Clinton. 8000 chip...brrr, that sends a chill up my spine just thinking about it! Maybe I'll start out with a 7000 chip and run it up a few hundred RPM more.
 On a side note, I tried the reground lifters once and lost an FK-87 with the. I also lost some stock SCAT lifters on an FK-8 before that. Now I'm running Udo's tool steel lifters and the SLR cam. Everything looked great on tear down but we did get some tool steel tips for the lifter end of the pushrods. They weren't pounded out yet but did show a little different wear than normal running against the tool steel lifters.

[RACECRAF]

I ran that same cam, but from Babe Erson before he passed, and was also a hard weld cam. Ran scat lifters, when I pulled it apart, the lifters were shinny, NO pits. Anyway, I used Berg 1.45's, the lift was .606 at the valve. I shifted at 6500rpm. That cam is a nice, still have it put away.

[Sparkmaster1]

I also use  that cam in a similar set up.  I shift at 7100 RPM's.... I'd also ask Darren for his advice.  Tim

[Mike Lawless]

A word of caution. Just because you CAN shift it at a high rpm, doesn't mean you should. If you're interested in longevity, keep the shift points down around 6500 and have fun for a long time. If you run it hard, get used to a heavy maintenence schedule.

[scott s]

 Mike, that's kind of my thinking right now and the reason for the 6600 rpm pill. But it just feels like the engine is nowhere near done. With that cam and the gearing I have it's still pulling HARD when it hits the rev limiter.
 I guess I'll leave the 6600 pill in there until I get a few hundred more miles on it anyway.

[Sparkmaster1]

I only shift at those RPM's when I'm at the track with.  When I'm driving it to work it rarelly see's above 5k.  Oh... and it gets about  24 mpg!!  Tim

[RACECRAF]

Thinking about selling my XR 310, hard weld cam with the lifters that was used with it, still good, but that would up to you. Any takers?? Note- Steve Long does not do hard weld anymore.

Ted