I just bought a longblock 350sbc (010 block).

It is a std bore with cast 12cc dish pistons
It has not been decked and has new bearings and rings.

So with the TBI 187 heads(1.84/1.5 valves, 58cc chambers) with a .040" head gasket it would be about 9.5 compression.
It currently has a summit cam (1103)
http://www.summitracing.com/int/parts/sum-1103

I also have a set of AFR 195 eliminators (65cc chamber, 2.05/1.6 valve).
With a .040" HG it would be about 8.9 compression.

This is going to be used with my LT1 intake(homebuilt mini-ram).

I just bought this engine just to get me through the season so I can cruise it.
I have a motown 400sbc block that I am building a serious engine for spring 2016.

I just don't want to sink alot of money into this engine b/c I will just sell it after the season is done anyway.

So my question is, how much more power would the AFR's be over the TBI heads?
Is it even worth it considering the 1103 cam that is in the engine?

 

Not to be mean or anything; but, do you REALLY have to ask?

You have probably the WORST flowing set of heads that EXISTS, and a set of top-of-the-line aftermarket heads. Hmmmmmm....... tough choice here...

Would you like a pile of elephant plop on your plate sir, or would you prefer the steak & lobster dinner instead?

 

Ya I would run the AFR for sure. Cant tell ya how much extra HP but they will make more. The cam will work just fine with the heads. Next time you find your self asking this question ask your self "What would Jesus do?"

 

Thanks for the replies.

So what would be the difference in HP?
30?
50?

Also, would I be better to switch back to the stock 48mm throttlebody?
I have a 58mm TB now

 

ALOT. That should be precise enough.

Does it matter exactly what the number is???

Would you screw up and use the TBI manure if the difference was only 47.6 HP; waver a little if the difference was greater than that but didn't make it to 58.1 HP; and then definitely make the right choice?

The 187s are better for other, lower-HP uses. Keeping doors open and maintaining boat location stability are 2 that come immediately to mind. In fact they would be FAR SUPERIOR TO the AFRs for either of those uses. So maybe it's true, for every thing there is a purpose...

The 48mm TB would be adequate if it was TPI. For a LT1 or similar short-runner setup, there's enough RPM capability, maybe even with that cam, that it might become The Bottleneck. In that case the 58 would allow the engine to get closer to its ultimate maximum HP potential.

 

My guess 60-70 hp, with 1.6 rocker

 

The AFR heads will pick up 70 HP over the 187 heads.

Also do not use a .040" head gasket. If block has not been decked, put a set of fel pro 1094 .015" head gaskets on it.

That will put you at 9.39:1 compression

 

The block has not been decked.

Do I need to straight-edge the block first?

How is sealing with the 1094 HG?
Is it like a copper head gasket?

 

THOROUGHLY clean the old gasket stuff off the block. THEN check with a straight-edge in 3 locations across the deck surface and diagonally in both directions (5 different placements if you're keeping track). Use a .002" feeler gague, even though the max spec is .004" out-of-flat for a SBC.

1094 will usually work fine but if there is ANY out-of-flat variance, use something with a bit more "squish". I like the GMPP .028" compressed thickness composite head gasket. They're tough as nails, they seal on spit and the price is right ($30 a set). I even use them on the mild blower motor in my Malibu. PLENTY tough. It's a good "in-between" choice between a steel shim-type gasket and the silly-fat FelPro rebuilder gaskets.

 

Could also use the Victor Reinz 5898 gaskets which are .026 compressed. Lots of LT1 guys use these to bring the compression up when they move to higher overlap cams.

 

Like damon said. Clean decks good, check for flatness.

Spray both sides of 1094 gaskets with the copper spray sealant and install.

No they are nothing like the copper gaskets. They are rubber coated steel shim gaskets