Ya, I wouldn't buy gaskets before checking what it's got. That's just common sense isn't it?

 

0.015" ... damn thats thin. That alone will add some crank. Hmmm...

Also, the pistons are down, what? about .030" from the deck on the average truck engine? Thats well within the 'decent' quench range...

I'd be a very happy man if i could get around .045" quench without touching the high-mile shortblock...

In the Mopar world, pistons are almost an eighth-inch down the bore...

 

.025" down the bore in a stock chevy 350. This is the advantage of a stock deck with the .015" shim gasket, good quench.

 

Even less? Is that ALL ov them? Like every one? I'm guessing the piston dish volume on a typical "8.2-8.5:1" 350 is about 5cc?

 

Same here... Only it was me who swapped in a 4 bolt truck block from a 76 c10 truck.. I put in .030 over flat tops without decking and .015 steel shim gaskets (for a .039-.041 quench if I remember right) with 64cc heads as well. My cam choices actually started to become limited at this point due to compression. I guess I played with fire and didnt get burned... Swapping to aluminum heads this spring as soon as its warm enough in the garage.and will be doing what Reelav8r did with copper coat as I used with the iron heads. I did measure my head chambers with the syringe because I bought them used and wanted to see what I really had but I have not yet done this with my aluminum heads.

@Pale Roader, my advise is to see what you have. A compression tester can give you a good idea. If you havent seen your pistons you dont really know if they are original or dished, flat tops or?

There are some good deals to be found from folks that just want the space back in their garage. I found my short block on craigslist for $300.. It supposedly had one summers use on a fresh rebuild. the shop that sold it to me swapped a 383 in the truck for the customer. In the end I did replace the crank and bearings because I saw some minor grooves (Shop told me they had a issue with a broken ring but it somehow didnt cause any block damage and all the crosshatching was still there.. Still, I lightly rehoned and reassembled using plastigauge and you tube videos and that was 9 years ago. Never did get the assemble rebalanced with the new scat crank but Ive had no issues. Found used 64cc iron eagle heads loaded with 1.6 RR (also $300) and I was able to through an engine together on a pretty small budget. If I had to do it again I may have gone 383 myself.

 

read the thread I linked above and you'll find out how big the dish in the piston is on a low compression 70's chevy 350.

5cc's would only be enough for valve cutouts on a flat top piston, and small ones.

 

i bbelieve the flat piston with 4 valve reliefs is 4ccs. the 8.2 to 8.5 engine is about a 12cc dish.

 

Google found this. So to answer you question, yes all of them, unless it's been decked. Another possibility is if the pistons are "rebuilder" pistons then the Compression height is different from the stock 1.56". Typically .020 lower to accommodate a decked block something like 1.54".
If those were installed and the block was not decked .020" then the pistons will reside .020" farther down the bore.

To find correct compression height take 1/2 the stroke add it to the connecting rod length and subtract that from your deck height, then subtract how far down the bore the piston is and you get your CH.

1/2 X 3.48=1.74

1.74+5.7=7.44

9.025-7.44=1.585

1.585-.025=1.56

1.56 being the standard CH putting the piston .025 in the hole with a stock piston with the stock deck.

If the block has been decked it may be any variation of distance between 9.0" and 9.25". How far in the hole the piston is may give you an indication of how much was removed. Otherwise it would have to me measured. Can't do it with a tape measure.

 

If you got the funds you can angle mill a 64cc head to a pretty small chamber if it's got enough thickness to do it.
Might have to check with a machinist or the manufacturer of the head to see if it's thick enough.

I'm running mine @55.5cs' with angle milling, 11cc dish pistons, .023" in the hole and the .015" felpro shim head gasket. Comes to 10.6 CR.

 

I only got 5cc's by using a simple CR calculator and reverse engineering. 16cc's... damn.

Kinda looks like i'm damned now, or damned later. I can either buy aluminum heads to make my old truck mess run, or i can buy some that will work... but with low CR, and hope to build a real engine with them someday.

 

Yeah, thats all on the option list too... but it adds up. Man everything adds up. Small block Chevy is supposed to be cheap! I'm not finding this very cheap at all.

THE ENTIRE POINT... ov this particular car, is to swap in a modern, all-aluminum V8, with all the tricks they come with. Now THAT... isn't gonna be cheap. If i can make this 350 move the car for under 2K, i will, but over that and i might as well just save up for the new plant.

I JUST missed out on a set ov used 195 AFR's here, for a decent price. Now, if something like that falls into my lap i might delay that new engine plan, but that doesn't happen often... even in Chevyland where i live.

 

2k is pretty tight.

Good deal on used heads or junkyard vortecs looks to be the best avenue for that.

 

That was my original 'interim' plan. But those L31's go for a lot ov money here. Its probably cheaper to buy the whole truck. Further, they're bloody hard to find used. Again, the only ones i've seen were still powering vehicles. Besides... thats STILL a $2500-3000 bill. They dont just bolt in. Thats one problem with owning a Chevy in Chevyland... everyone else here is scrounging for the same damn parts...

 

I agree with Stormin Normin on the Dual Plane Intake!

Rick

 

Here's a cheap aluminum head. Are you ready to roll those dice?

Flo-Tek 102505 Assembled S/B Chevy Aluminum Head, Straight Plug (speedwaymotors.com)

Scotty

 

Anything i buy, from cheapo Chinese suspicion heads to new AFR's is going under my engine guy's microscope regardless. As long as he doesn't need $200+ to fix whatever's wrong, i'm good. 240/180cfm seems hardly impressive though. Edelbrock was pushing that through a 'cheap' street head 25 years ago.

There is also this head, a supposed AFR Enforcer casting, assembled, 64cc, for about the same price, on Ebay ($615US). They were linked in another recent thread. They look decent too, and i'd imagine, if they ARE the same casting as the AFR, they'll flow better and have a nice chamber.

 

tpi421vette in the C4 section can get you a killer deal as hes an afr dealer. Just got a set for a forum member last month.
Cheaper than summit..give him your cam specs the springs will be set up for it. They can mill if need be, pretty reasonable
They use pac springs and the 8mm lightweight valves. Got a few bare sets of those but use std size stems

Anyway his name is Jim Barth if you need his # pm me


Edit: wondering if you could get enough for your take off heads to grab a set of iron Dart iron eagles?

 

I agree wholeheartedly, bought a set from him this winter. Great guy !!

 

Good to know!

As for iron... if i'm pulling the heads, i'm saving 40lbs. Otherwise i wont bother. 40lbs is literally as important to me as 40HP. I found some used Vortecs nearby... but they're still iron.

 

You can buy those casting AFR and Blueprint uses, bare on amazon or ebay for like $325- 350 a pair. Thats what I did so I could experiment with porting them. Then I bought the shims comp seals,springs, retainers guides & gatorman valves. I had a machine shop recut the exhaust seats to work better with the valves I purchased and it all still was under 800.. just something to consider because ive read on other forums the springs included in the cheaper preloaded heads are really weak (although maybe thats what you want for certain flat tappet applications)..

If I were looking for cheap preloaded versions of these I would feel comfortable buying these for a bit more. https://www.ebay.com/itm/33391577918...QAAOSwZQxW2LMx Skip has been selling these for years and I think he was the first honestly. It sounds like the forum member above is a good option too since he can tailor to your cam choice.

I found those 58cc aluminum heads you talked about earlier but I havent seen them in a while.

Ill be selling my old iron eagles this summer but they arent exactly economical to ship anywhere