Camshaft decision help

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CHEVYS4ME

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Ok, not really decision help, but total help!

91 C1500 5.7 700R4

I have Summit shorty headers
46mm tbi base
3704 and spacer bored to 46mm
EBL Flash II (not yet installed)
Vortec Fuel Pump
Adjustable Bypass Regulator
Summit Racing 162108 Heads 62cc
1700 Stall TCI Converter
Optmum EFI billet Injector pod w/2 smaller 40-70 lb hr injectors
My guess is it will be about 8.9:1 compression ratio

Looking for a nice flat tappet camshaft that will pass CA emmissions, but yield most power, best vacuum, and possibly a slightly lopey idle. I dont care about eo number as i just bought an edelbrock cam with eo number and i can just use that number.

I have had really bad luck with the last engine I had installed. Already have metal in oil.

Im going to purchase the ATK sp03 high performance short block https://www.summitracing.com/parts/hpe-sp03

My cam, lifter, and oil pump will need to be replaced again.

I want to get this order in tonight. I have everything sorted, but camshaft choice.

Any suggestions will be greatly appreciated!

Thank you in advance...
 

CHEVYS4ME

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Yep, trying to stick with 112 which both of these cams have. Looking for specific cam advice to purchase one wihin a couple hours...

Im leaning towards the 2102 since I will be custom tuning it with the EBL Flash II I just purchased for it. I will be custom tuning after i get it on the road, and smogged.

Edelbrock 3702 vs 2102 specs

[email protected]
194/214 vs 204/214
Adv Dur
244/264 vs 278/288
Lift
.398/.442 vs .420/.442
Lobe Seperation
112 Degrees on both

I think it should run pretty good.

Im NOT a fan of Edelbrock Camshafts at all though...

Any thoughts on a good TBI cam for my setup, anybody???
 

SAATR

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You're leaving some power on the table from the start by keeping the 8.9:1 compression with the head upgrade. Bumping to at least 9.5:1 would have been better, and would have cost nothing in terms of fuel selection. Given that, you'd probably do well with a comp xe250h-10. Slightly tighter LSA at 110, but only 1 degree more than the factory Vortec cam. Also, the 206/212 should be better than the 204/214 with your heads, as I imagine they have slightly better I/E flow ratio than the factory heads and shouldn't need as wide of a duration split. Staying smog legal is the biggest impediment, but what can you do? Going to a 212/218 like the xe256h would net more power, but I can't say where it would leave you emissions wise, and may be detrimental with the lowish compression.
 

PlayingWithTBI

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I have the Lunati Voodoo 10120700LK with 1.6 rockers. It idles smooth but gives great low end power with 207/213 and .466/.484" (1.6 full roller rockers) with the same heads you have. If you want a little more you can go with the 10120701. The reason I went with those rockers is, if I don't pass emissions, I can switch back to 1.5s then swap them back.
 

PlayingWithTBI

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Why would you drop all that money on parts and put a flat tappet cam in it?
Good point but, these blocks may have come with the bosses for the spider but they probably weren't drilled and tapped for the spider (mine wasn't), let alone an additional $500 for the roller cam, lifters, dog bones, and spider. I thought about it long and hard but had a hard time justifying the added cost. After all was said and done plus ~$8000 later (including blowing my 700r4 LOL) an extra $500 doesn't look all that bad huh?
 

PlayingWithTBI

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My guess is it will be about 8.9:1 compression ratio
You're leaving some power on the table from the start by keeping the 8.9:1 compression with the head upgrade. Bumping to at least 9.5:1 would have been better, and would have cost nothing in terms of fuel selection
I don't know but, I thought the TBI 5.7L with 65cc 193 heads and 12cc dish pistons was closer to 9.5 CR, these 162108 heads are 62cc so CR should be higher, maybe closer to ~9.7?
 
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