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Old 04-20-2017, 10:35 PM   #1
bautino95
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402 cam help

Hi, I have a 71 lwb c10 402 engine and th400 tranny. I already pulled the engine and had the machine shop go through the heads (#3993820). The block was in good shape so I just gave it a hone, new cam bearings, freeze plugs, new rings, and new main and rod bearings. I plan on adding a Edelbrock performer intake and 750 carb. And maybe headers at some point. So my question is what cam do you think I should put in it. I want to be able to run with my stock valve springs so going too big is out of the question. I was thinking of a comp cam 260H or Lunati 250/256 or 256/262 Also would it be worth changing the torque converter at this point too? if so what stall speed? Trying to do this on a budget so no roller cam on this rebuild. Thanks
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Old 04-21-2017, 07:42 AM   #2
hugger6933
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Re: 402 cam help

Call Comp cams[ 1 800 CAM HELP] and ask them I have had great luck [in small blocks ] with the 268H and I think they work just as well in big blocks.Keep in mind that when most talk about a big block cam they are thinking 454 and not 402. A cam that is just right in a 454 will be a shade too big in a 402. But since you are wanting to stay on the small side I still think in the 268 range is just where you will want to be.
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Old 04-21-2017, 07:59 AM   #3
Mike C
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Re: 402 cam help

Calling Comp a great idea. But the 260h is a great choice as well. I prefer straight pattern cams, but as you can see most current grinders use split patterns. The 260 should not require a converter change.
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Old 04-21-2017, 09:06 AM   #4
engineer_gregh
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Re: 402 cam help

I'm running 268H in mine and love it. I did put a 2200 B&M Hole Shot stall in as well.
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Old 04-21-2017, 10:03 AM   #5
weq92f
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Re: 402 cam help

Quote:
Originally Posted by engineer_gregh View Post
I'm running 268H in mine and love it. I did put a 2200 B&M Hole Shot stall in as well.
How does it idle?

-klb
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Old 04-21-2017, 10:32 AM   #6
engineer_gregh
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Re: 402 cam help

https://www.facebook.com/10001020027...4410215575653/
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Old 04-22-2017, 02:32 PM   #7
bautino95
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Re: 402 cam help

thanks for the input everyone. My brain is going to explode with all the options out there. So I'm down to these options to run with stock valve springs:
1.Comp recommended the 260H cam P/N 11-203-3
2. Lunati recommended the 262/272 high efficiency cam P/N 10110212
3. And I thought I could get the Summit racing cam SUM-K1300, its close in the specs but they recommend new valve spring. I think there just covering there butt by recommending the valve springs.
Sorry I dont know how to make links to the different cam pages.
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Old 04-22-2017, 04:07 PM   #8
68Gold/white
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Re: 402 cam help

268H, absolutely! Just make sure it is NOT the X/E version!!!

Knowing the chamber volume would help determine things better. Flat top pistons? zero decked?
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Old 04-22-2017, 06:07 PM   #9
bautino95
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Re: 402 cam help

heads are 113cc (3993820 casting) pistons are stock domed, and the block has not been deck. now I called Competition Products today because there the only ones open on saturday for teck support. and they recommended this:

Elgin, Hydraulic Flat Tappet Camshaft, Chevrolet Big Block, 208/218 @ .050, .475/.500, 112 LC
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Old 04-22-2017, 07:09 PM   #10
Mike C
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Re: 402 cam help

210 at .050 is what the Comp 260 is and 218 is what the 268 is, so that is basically a split pattern cam with the 260 intake and the 268 exhaust. But 112 instead of 110 lobe center. Would be good for FI in the future.
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64 Corvette Coupe
68 Camaro 'vert LT1 & TH700
69 Z/28 355 12.6's @110
72 Jimmy 4WD 4spd 4" & 35's
72 240Z-2.9l L6, triple Del'Lortos, T5, 12mm R200 LSD
85 FJ1100 & 01 XR400
86 Kawasaki X2 & 89 SX650 w/PJS cylinder and dual carbs
02 GMC 2500HD 4x4 Duramax
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