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Discussion Starter · #1 ·
i have a set of aluminum LT1 heads. all the work will be done by me and my father. there are a few things we need to know first. we want the heads milled down a little for higher compression. i dont mind running premium grade. how much should we take off? what thickness head gaskets? and for the cam, i want the most powerful cam with the most lumpy idle i can run with 3.08's and stock stall. :( pops won't allow any stall/gear mods. i was thinking 227, ZZ3, 305? headers, 1.6 RR's, valve springs, and Herter PCM will be installed all at the same time. thanks for any info.
 
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Discussion Starter · #2 ·
would somebody explain the logic behind having a really powerful engine but leaving the rest of the drivetrain stock? :rolleyes:


Hmm, how about these lobes from Comp 3118intake/ 3109exhaust on a 108+4LSA for an idle similar to the hot cam but should stay low in the RPM range because the duration is less than the ZZ3's.
 
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Discussion Starter · #3 ·
the logic: its dad's car. i just drive it.(only 17) he says no stall/ gears, it gets no stall/gears.
i didn't say i wanted an extremely HOT cam. i just want to know what the BIGGEST cam i can run with the stock stall is. can anyone help?
 
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Discussion Starter · #4 ·
GM 845 or Comp Cams 501 XE cam are probably be the best choices for your application. Crane 227, GM ZZ3 and CC 304 are a little milder and will work fine. You will need to upgrade converter/gears with CC 305.
 
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Discussion Starter · #5 ·
If you want a cammy idle but need good low end for torque, the solution is to get a cam with a narrow lobe separation angle (LSA) but not too much duration. The narrow LSA will provide the cool idle, while the small duration will give power down low where a stock converter can take advantage of it.

A good cam to look at is the RamJet 350 cam. The lobes are only slightly larger than the stock cam, but the LSA is two degrees closer together, giving a lumpier idle. When you get the engine tuned for the new cam, turn the idle down until the idle suits you. This cam gives the the same torque down low as stock, but makes about 50 more horsepower at 5000 rpm.

Or, if that's not enough, you can get a custom cam designed that has a REAL narrow LSA - like 104 degrees or less.

HTH,
 
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Discussion Starter · #6 ·
Originally posted by 94SSman:
the logic: its dad's car. i just drive it.(only 17) he says no stall/ gears, it gets no stall/gears.
i didn't say i wanted an extremely HOT cam. i just want to know what the BIGGEST cam i can run with the stock stall is. can anyone help?
No offense to your dad, but does he know what a stall converter really does? My dad didn't and he was into hot rodding when he was younger. He didn't like it that I was putting the Vigilante in my SS. In fact, when the rear end broke, he blamed the converter :D :rolleyes:

Anyway, read what the other guys have posted. Then look at the lobe specs that I posted above. here they are again:
3118 Comp Magnum lobe for the intake, 260*advertised duration, 206*[email protected], 126*[email protected] .500" lift with 1.5 rockers, .533" w/ 1.6 rockers

Comp 3109 Magnum lobe for the exhaust, 276* advertised duration, 220*[email protected], 138*[email protected], .510" lift with 1.5 rockers, .544" w/ 1.6 rockers

If dad's an old school hot rodder tell him it's a 260/276duration cam. Overlap would be 52* @ advertisded and -3*@.050. For mild heads with stock converter and gears, it should work very well.


I might also consider this grind:
Comp Xtreme Energy 3312 lobe for the intake. 266adv, [email protected], [email protected], .488 w/1.5, .520 w/1.6.

Comp XE 3314 lobe for the exhaust. 276adv, [email protected], [email protected], .503 w/1.5, .536 w/1.6

It's a 266/276 cam with more aggressive lobes. It would give a little more overlap (55*@adv & 0*@.050) and a meaner idle. You'll lose a little low end, but you'll gain even more top end. Plus, if you do ever change the stall and gears, this cam would work better with them.

I'm suggesting going with a 108+4LSA on both so you'll have plenty of torque and a mean idle
I wouldn't suggest forced induction with this and nitrous wouldn't be optimum.
 
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Discussion Starter · #7 ·
thanks for the info. would the GM HOT cam be ok with the SLP 2500 stall? dad sounds like he may approve of a stall now. :D does anyone have any input to the heads question in the original post?
 
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Discussion Starter · #8 ·
How high do you want the compression? I feel that 11:1 is a safe zone to run in... Rule of thumb is that for every .010" you shave the heads or thinner gasket that you increase the compression by 1/3 of a point.. If you start off with 10.2:1 and shave off .020" then you will end up with a 10.8:1. The .026" gasket will give you another .003" over the factory .029" gasket increasing your compression up to around 10.9:1.

I'd fly with that.... Talk to your machine shop and see what they think.. You will also want to get your heads CC'd before anything is done to get a more exact compression figure though. I say that because they may come out as 62cc chambers instead of 64cc, so your compression is already up there a tiny little bit more.

-Tom
 
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