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Old 09-14-2018, 10:19 PM   #1
Domingo
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Summit heads?

Im going to be pulling the sbc 350 out of my c10, because of a flat cam lobe. While at it I was thinking on replacing my heads with some from summithttps://www.summitracing.com/parts/sum-152123 and summit's 1103 cam. The reviews at summit website are mostly 5 stars. Anyone here running them
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Old 09-15-2018, 02:48 PM   #2
geezer#99
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Re: Summit heads?

There’s more to it than just picking some heads that are priced right and have good reviews.
Those heads won’t change your compression very much. You’d be better off with some 64 cc heads.
That cam is too big for either set of heads. Yours and the summit ones.
What’s your intended purpose for your motor?
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Old 09-15-2018, 03:16 PM   #3
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Re: Summit heads?

My opinion is that will be a good setup if you need to go through the heads. I also would go with the 64cc head if they offer that.

We put the Summit 204/214 cam in my kids Jimmy motor and it's not on the road yet but I think we should have gone with the 214/224 cam you are looking at. We have broken the cam in on my engine run stand and it idles smoothly at 650 rpm.

He has 3.73 gears and a 2000 rpm converter so we could have gotten away with a little more cam I feel.

My Jimmy has a 331" small block with a Crane 266 cam (210 @ .050, .440 lift, 110 LSA) and it has plenty of low end. With the auto and more displacement I don't think the 214/224 .050 duration is out of line at all.

Based on machine shop costs in my neck of the woods, makes zero sense to R&R your OEM heads when you guy buy upgraded new ones for that kind of money. I had the 290 oval ports rebuild on my L36 427 and it cost almost $1200. I wish I had ponied up another $600 for the Edlelbrock oval ports.

edit: looks like Summit only offers the 72cc head which will give you a 1/2 point compression over stock almost. Which will also allow for the bigger cam.
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Old 09-15-2018, 04:19 PM   #4
Domingo
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Re: Summit heads?

The truck now has a sm465 with 4.10 gears and a 30 inch tire. The plan is to replace the 465 with a car 4 speed. I was thinking of 72cc and could still use cheap gas. I want to make it a daily driver. If i go with the vortec, I'm going to need a vortec intake, valve covers, rockers. Price goes up. In the case I'm better off picking some aluminum heads(blue print) are about $900.
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Old 09-15-2018, 09:59 PM   #5
Mike C
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Re: Summit heads?

You will be fine with that cam with your setup. Vortecs are great, but you are right that there are additional costs if you already have an intake.

I had a Cam Dynamics 284 cam (228@.050) when the 331 in the Jimmy used to be in my Camaro. With 4.10 gears and a 2800 rpm converter it worked well. When my Jimmy timing chain broke on the original motor at 252,000 miles I swapped the 331 in because it was just sitting in the barn.

Let me tell you, with 3.07 gears, 33" tires and the SM 465, that was NOT the right cam! LOL. I swapped the cam to the Crane 266, the Z/28 intake for a Weiand 8004 and a Q-jet. Along with 4.10 gears and 35" tires that has proven to be a good combo. That motor has been in the truck 30 years now. At some point I will go 383 with a cam between 214 and 218 at .050

That motor has 186 GM heads and TRW forged flat tops in it. 9.8:1 maybe? It runs just fine on 87 octane as well. If making max power is your goal, I'd save for the aluminum heads. Maximum torque is dictated by displacement and compression ratio.

Have you ever bought from Competition Products? They own Howards Cams (I think, or are at least in the same town) and are an Elgin dealer. Pretty sure Elgin grinds those cams from Summit. But there are more cams in the catalog that may be even better suited you may want to check out.
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Old 01-27-2019, 02:54 PM   #6
Greasey Harley
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Re: Summit heads?

Had those heads on a 383 with flat top pistons and a moderate flat tappet cam. No complaints. That thing ran like a scalded dog.
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Old 01-27-2019, 07:04 PM   #7
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Re: Summit heads?

I wouldn't go 72 cc chambered heads, your compression will drop so low you'll have a turd. 64 would be the biggest chamber, remember lower compression lower power means inefficient it will defeat the purpose, and its a truck it needs torque.
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