Need to identify a CS771 camshaft

I am trying to tune my 1984 Corvette Crossfire 5.7L engine with a cam that I can only identify as a CS771. It is supposed to be a little hotter than the original Corvette was. The engine was built in 1992 but has zero miles. I have modified the Crossfire TBs by installing matched 5235206s. I removed and capped off the original regulator and accumulator and feeding both in parrallel with a Mallory regulator. Am now trying to tune the 1227747 ECM and having trouble with setting spark to zero and getting a decent idle. Googling CS771 camshaft netted me several different cams.
My main purpose for this inquiry is to rule out the cam as the problem. Any help is welcomed. The engine is in a 1949 GM pick-up with no EGR and no cats yet. Bob

Correction: Built in 2002.

So I type in CS771 camshaft and Google immediately comes up with Sealed Power CS-771 camshaft. What's the trick? Then I realize... many of the listings are for 7.3 Ford engines. No problem, the number CS-771 is for a cam family. You can call Sealed Power / Federal Mogul tech support and they'll give you the specs! You could also:

1) Ask this guy for cam specs:
http://www.ebay.com/itm/McFaddens-Se...JVefbi&vxp=mtr

2) Trust this Ebay auction that says CS771 is the same as CS766 and go with the listed CS766 specs:
http://www.ebay.com/itm/Engine-Camsh...-/191674229890

FWIW this seems like a fairly mild cam.

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Originally Posted by 1project2many

So I type in CS771 camshaft and Google immediately comes up with Sealed Power CS-771 camshaft. What's the trick? Then I realize... many of the listings are for 7.3 Ford engines. No problem, the number CS-771 is for a cam family. You can call Sealed Power / Federal Mogul tech support and they'll give you the specs! You could also:

1) Ask this guy for cam specs:
http://www.ebay.com/itm/McFaddens-Se...JVefbi&vxp=mtr

2) Trust this Ebay auction that says CS771 is the same as CS766 and go with the listed CS766 specs:
http://www.ebay.com/itm/Engine-Camsh...-/191674229890

FWIW this seems like a fairly mild cam.

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Thanks 1P This was more than I hoped for. I can eliminate the cam and concentrate on tuning. Still have to find out why it needs so much spark to start. Getting a little exhaust smoke and plugs are fouling fast. Put in the Moates adapter and using AHAK but have yet to get the laptop connected. But IT RUNS!

Are you using the stock '84 heads? They are old heads that will require a fair amount of advance compared to the heads most likely used with the TBI 7747 truck. Also, have you adjusted the injector constant? Switching to the larger injectors will mean more fuel delivered per pulse. IIRC the original injector constant was smaller than a 5.7 truck or van.

[QUOTE=1project2many;61410]Are you using the stock '84 heads? They are old heads that will require a fair amount of advance compared to the TBI heads most Also, have you adjusted the injector constant? ]
Heads are original. That answers the advance question. Thanks
Haven't changed the injector constant yet. Is that BPW? BPW is at 135 now. This would explain how I got it to a decent idle last time it ran by dropping the fuel pressure way down. Less than 9 psi IIRC. It's at 12 psi right now and getting smoky ex. Plugs are pretty black too.
Really appreciate your help with this.
Bob

Yes, BPW is the base fuel constant.

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Originally Posted by 1project2many

Yes, BPW is the base fuel constant.

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Thanks 1p I re-ran the BPW calculator and still came up with 135.
From what I've found in searching for injector flow rates on 84 CFI the flow rates are
about the same as the new injectors but the new ones are matched.
What am I missing on BPW? Is the small TB diameter a problem?
Another question. What plugs would you recommend for this set-up?

I believe I ended up around 128 when I put the 7747 into my pickup. I'll see if I have a copy of that file handy.

I'd run a standard reach Delco plug in the "45" heat range.

Quote:

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Originally Posted by 1project2many

I believe I ended up around 128 when I put the 7747 into my pickup. I'll see if I have a copy of that file handy.

I'd run a standard reach Delco plug in the "45" heat range.

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Thanks again 1P. O'Reilly's is getting me a set of AC-Delco R45TS plugs tomorrow and the recommended gap is .045.
I'll try 128 unless you come back with something better.
Just talked to our local hot-rod guru and he recommends about 8 to 10 degrees of advance to begin with. See what I can come up with.
Guess I should look in my storage and find my scope. This project is really getting to be fun.
Bob