here is my goal: right now i want to build a 350 up to handle a supercharger (not sure what psi right now) and about 400-500 hp.

so i am shopping for a good block what should i look for. i found this one for $300--is it a good deal-->
"Late model bare factory 4 bolt performance block. This is a one piece rear seal and has mounts for a rollor cam. Block has had all plugs removed, thermal cleaned, and magged for cracks. Bore is standard but would need to go to .020 or .030. A nice start for a restoration or performance buildup. Casting # 14093638. Rear of block has 5.7LG / SGI with a date code of A 10 9."
This is going to go into my 87 Iroc..sorry this is all the info i have...do you need more info to answer my question..

also i would like to get it bored 30 over...who has done this and how much did it cost (i am thinking about getting it done at napa) is napa good? or are they over priced, i want it done right...thanks for any help and/or comments

 

Unless you just absolutely have to have the late model block, I would skip that one.

The best factory 4-bolt blocks are the 1969, '70 and '71s. A good source for this block is in a 4-barrel 350 Impalas, Chevelles, Camaros, Novas, 'Vettes and trucks. Generally, these 350s were known as 300 horse-350s. Most also had the 010 casting code.

These blocks are thicker, have better material and will bore to a larger oversize easier. The mid-70s and later 4-bolt blocks were lightened considerably from the factory. Not good for a blower engine.

The down side is the dip stick tube is on the driver's side, two-piece rear seal and related crankshaft and no factory provisions for roller cam.

However, if you're planning on a blower, you'll find a much better selection of cams for the early model block using regular lifters.

Also, $300 is pretty high for a block that "may" clean up at .030.

Those early blocks are out there. I've even bought the entire car for just the engine and sold the car body to demolition derby guys for enough to cover the car's initial cost.

An added bonus to the 300 horse 350s is that they have some of the better factory heads (double-humps with the bolt holes in the ends of the heads) which can be sold to help cover building costs (or you can use them yourself).
jms

[This message has been edited by jms (edited June 17, 2001).]

 

now what if i wanted to stay with TPI?? cause i want to have this car as a daily driver and i dont want the people at the local shore stop knowing me on a first name bassis?? if i get the 350 block out of a carbed engine does that mean i have to stay with carb or can i just get diff heads/intake and all (what ever i would need) to go TPI? i never really thought about that till now...butt thanks for the great info!

mike

 

The block doesn't care what kind of small block heads go on it. Just use a matched cam/intake/head set-up. In other words, don't use heads designed for 7,000 rpm with an intake designed for 5,000 rpm and a cam recommended for 4,000 rpm. Get a matched set-up with your future plans in mind.
jms

 

Any 4 bolt block is a good starting place. I like the newer one piece blocks since you can run a roller cam cheaply.

The older 4 botl blocks with the 010 and 020 castings are the best blocks in the sense of the materials used. But ask people what is the weakest link in a SBC. Usually a rod will let go. The minority of problems are from blocks. Sure there was years that were prone to cracking, but those were the mid 70's and early 80's.

If you have a factory 4 bolt with roller cam setup, that is from a truck, so it is what GM called a heavy duty block. Some even came with forged cranks and also had some secret codes equivilent to the 010 and 020 codes.

If your block checks out, then you have a good starting point. For severe duty, I would consider puting studs in the block. Run some aftermarket rods, H-beam would be nice, but costly. A forged crank is a necessity if you are running all out all the time. If it is for street use, a preped cast one that is limited to 5000 rpm will live for a while. But once you are at this point, consider a forged unit. You can use the 1 piece to 2 piece adapters that will allow you to use an old style forged crank in the newer block.

If money permits (and if you bought all the fancy stuff), balence everything.

Forged pistons are a must as well. No hyperubreakit version. They don't like pressure, well that's not entirely true. Better stated, they don't survive well under the wrong circumstances. Forged are more fogiving.

Things get expensive if you do it right. If you are not winding it up on every run, then you can certainly use a lighter duty setup. But a piece of mind is nice to have.

Hope some of this ramble is of use.
Mark.

 

In addition, if you are looking to get your block bored, any reputable machine shop should be able to do it. How they finish it might be different.

I would also ask them about squaring the block. IE. Make sure the block will yield the same deck hieght accross cylinders. It is not uncommon to see quite a variation in stock blocks. If you want to KNOW for sure, then measure your block. IF it is out, then get them to deck it so all cylinders are the same.

Go in person to a couple of local machine shops and ask them what they do when they bore a block. You will see a difference. Ask them what they recommend. Play dumb and listen, and then compare what you've learned.

$300 for a bare block is not a great price. I have bought complete short blocks for less. Some of them needed to be bored, some didn't. When you bore the block, then will clean and check it for you. It is almost better to get a block with crank and rods. Then when you take it apart, you can see how the engine was.

Mark.

 

wow...thanks for all the great info...now as far as prices. i know people dont like to give prices on this kind of thing because it is like a paint job...the better the paint job the more expensive. BUT what should i look for as far as price for:
stock engine bored 30 over
squared
hot tanked
magnafluxed
what else do you guys recommend?

i was debating on weather to buy a block that had all this done to it (off like someplace like e-bay) or go to a junkyard (or e-bay) and get a plain block and then pay to get it all done. that is why i want the prices to compare. either way i wated to keep my car drivable till the engine is done. and thanks again for everyones help

mike

 

I got my 350 4bolt 2 piece for 300.
That was already done and ready for the rotating assembly
I find it is easiest to just find a local motor rebuilder and check out what they have.
If ya need them to put it together too they might give ya a package deal.
That way you don't have to pay $100 for shipping and handling on a motor that is not worth much more.

 

rebuildable 350 go for around 225 here....That is the complete engine.

 

its best to take your pistons with you to get the block bored so they can match bore your block. forged pistons require more clearance than hyper. and cast. so its best to have everything ready before you get the block work done. only down fall is i bought 30 over pistons then had the shop match bore the block to these pistons and the block needed to go 40 due to a scratch on the cyl. wall. but they traded my block for one they had laying around so i got lucky.

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92 z28 170,000 miles 14.20 on goodyear eagles before exhaust only mods k&n and slp 13/4 headers and dual 2 1/2 exhaust
87 trans am 12.20 on motor too many mods to list