brain

I think a 108 is too tight unless you just want it to cam a lot. If I recall, my car trapped around 110 shifting at 6200, and went 113 shifting at 6600. 110 is no slouch in my book for a cam only LT1. You'll be lucky to see that with the 224/230 from what I've seen of the cars with that cam.

FWIW, I did degree my cam when I installed it. It doesn't give you anything but assurance that it was installed correctly and that all the stuff is right. Why wonder if theres something wrong down the road?

Kevin Blown 95 TA

"want it to cam a lot" - WTF does that mean?

JoeliusZ28

"Cam alot" = lope, surge, kick-in-the-*** top end.

this would be achieved by overlap, which is determined by duration and lobe seperation angle.

And i want my car to "cam alot" so thats exactly why i want a tighter LSA.

brain

Yes, lope. The tight LSA will do that, but that duration you chose won't do much in the kick-in-the-*** top end. I think the 847 is a much better choice for your application. 108 is real tight. Isn't the Hot cam a 110? It "cams" or lopes about the same as the 847 IMHO.

JoeliusZ28

i thought the hotcam was a 112... could be wrong though.

to quote zigroid:
a 108 LSA 224/230 would have significantly less overlap than an 847. Remember im using stock heads, so its better to make the power where i can use it - which is under 6200 rpm. I would agree that it wont make the same peak power, but it will probably have much more in the useable power band.

I only know of one person who has done the 110 and he not only liked it, he recommended to me a 110 +4 or 108 +4 (this was a while back). I personally dont see why not give something different a try.

brain

But it won't make more power in the useable power band, I hate to say. I've compared MANY a dyno chart, and none come close to the 847 in overall power under the cuve, even if you limit your range to 6200. I'll do some searching to see if I can demonstrate it.

JoeliusZ28

im interested in seeing what you find.

Zigroid

here are two graphs. 1st is brain's GM847 and bolt on dyno, 2nd is a custom cam by bret bauer and his bolt on dyno from this thread.

brain's


jon A's


here are the two graphs overlayed the best I can:


cz28.com kinda squishes the image. right click and hit properties then copy and paste the link to your browser window for a better view.

JoeliusZ28

the custom cam appears to have the exact same curve... just less power up top. but i dont know how to compare this since i dont know the specs on the BB cam.

Rising Phoenix

Interesting to see this dyno graph. Comparing it with my car (stock exhaust, cold air, rockers, tune, lightly hand ported heads) the power and torque at 1500-2000 are about the same as mine, and then of course the difference grows as you rev past that. Also interesting that the peak power is made only about 400 rpms higher than mine which appears to peak at about 5400.

Thanks for posting that.

Zigroid

GM847 actually makes more power sooner. Bret's cam looks more liveable down low but its hard to say.

JoeliusZ28

i wish i knew what the specs of that cam were... cause thats just making me want to get an 847 again.