twcblackhand6970

I plan on buying a gm847 or similar cam soon and want to know exactly how high you can rev a stock rotating assembly with good springs a 1.6 rr without affecting its reliability. I also plan on getting le2 heads in the summer so i know the whole "not going to get full potential until heads are ported". I just don't want to have to spend money buying two cams (one now and one after I get heads ported) and as long as the gm847 is a step up from the stock cam, I'm happy. I will get the PCM retuned by Madz28 after the cam is installed.

So to restate the question. How high can you safely rev a stock lt1 without affecting its reliability because it is my DD and I don't want to blow something out.

Also how much would the cam bring my city/hw gas mileage down. And if the 847 is too big, how about the cc306?

..DAMN..

I have mine set to shift at 6k and it feel's like it makes no power up that high! Now i am running a stock cam so that must have alot to do with it but i wouldnt run it any higher than 6k.

twcblackhand6970

I think my comp is set to shift no higher than 5900RPMs right now.

Aside from that, besides getting springs and rockers for the new cam, what else should I replace? Pushrods and Lifters?
Any part numbers for them too would be helpful.

rskrause

There should be no problem up to around 6,500.

Rich

Z-RATED94

My small cam likes 6400 as the shift points NA. But since I'm stressing out a few important pieces (stock shortblock, trans, rearend) I have the shift points set at 6200 on the nitrous.
I agree with Rich. I woundn't spin it past 64-6500rpm.

twcblackhand6970

so stock shortblock can spin 6400rpm safely without affecting its long lifespan of 100,000miles plus.

KajunKadillac

6K is what im going to set my max RPM when i do my 383 build on a lt4 hotcam. Check the rpm range of the cam you want/have and determine it from there.

twcblackhand6970

yea, I want the a cam that'll go from 2000-6200ish. I was just worried about the shortblock not handling the spin.

twcblackhand6970

so could I spin it to say 6200rpm with a cam similar to the cc306 and gm847

Z-RATED94

Both of those cams would want more rpms. My small cam peaks around 6k, and the shift points are 6400 NA and 6200 on the bottle. You need to think a little smaller. Then again you need to think a little bigger on your converter.

wrd1972

Of course you could, but you wont reach peak HP. Take that to the bank. Those cams want ~6.6K RPM to reach peak HP.
All things being equal and shifting at 6.2K, a CC503 would smoke the CC306.

Stock short block reving over 6.3K is a crap shoot. Some make it, others dont. Depends on the condition of the internals and how well the motor was taken care of.

LSWHO

On stock heads those cams peak before 6k rpms. 6500 is plenty.

wrd1972

Yeah, I would agree with that.
Still a bad choice on stock heads.

twcblackhand6970

I plan on getting LE2 heads in the summer and don't want to buy a second cam when I get heads. What would be the biggest cam you suggest to rev to 6.2k and have a big lope to it. And I've got the small stall because it's my DD, I don't plan on launching out of red lights/stop signs at 3k.

wrd1972

My LE1 shifts at 6.3K and has a good lope to it. Talk to LE.