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I'm trying to evaluate a V8 engine for transplant, but I am wholly ignorant and need some help. This is for my 85 El Camino 305V8 with (I think) 200c trans.

I need to replace the current 305 V8. Not looking for max power here, just a good cruising engine that gets reasonable gas mileage and is very streetable. I won't be racing it or towing anything.

My mechanic has a 1975 2 bolt 350 (I'll get the date code and stamping info to confirm) that he pulled a few months ago from a customer's car and replaced with a crate engine. It's a short block, more questions about that in a bit.

He says it has about 2K on the clock, customer ran it too hard and caused damage to #2 piston skirt. It's bored .060 over and balanced. No ridging on the top of the cylinders, the bores look very clean. Mechanic says he'll replace the piston. It's a steel crank, don't know if it's forged or cast, I'll find that out, is either one OK?

One of my concerns is overheating because it's .060 over. Among the freeze plugs installed during the build, one of them has a lead insert that would melt if the engine ever overheated, and it's intact. I've never heard of this type of freeze plug, is this for real? Is a .060 overbore inherently prone to overheating?

About the short block: mechanic says using the 305 heads on the 350 is a good combination for power and he'll grind the valves on my heads. He also says the 305 4 BBL carb and intake will work well on the 350, and can be later switched over to a FI system easily. True?

Lastly, I'll probably be ditching my current 200C transmission and getting a 700r4, in case this makes a difference on the 350.

Thanks in advance for any and all help!
 

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There are real experts here who can fill you in on the details.

Before we go too far...what price is he offering you the short block for?

Sixty over is a lot of overbore, but not outside the realm of dependability. That would make it...what...about a 364?

All the stuff on your engine should fit on that block. Again, that's the advantage to Chevy engines over Ford engines. The 305 heads will work, but it won't be zippy. I doubt it needs a valve job, but that will be up to you. It could probably use new valve seals. Those heads should have hardened valve seats to work with unleaded gas, so that's not a problem. The intake manifold, carb, etc., are all the same. Even the flex plate should be fine.

Now...if he was the mechanic who built the short block in the first place, I'd be a little nervous. I'd worry that the new piston wouldn't match, or would have some other problem.

Again, the price he's offering the short block to you would be critical. If he's talking a couple hundred dollars, that's one thing. Keep in mind you can buy a new crate motor long block for about $1500, delivered.
 

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I'm not to sure I'd like the bored over 60 thing, that’s a pretty big bore. 30 over would be more to my liking. And your mechanic saying (he ran it to hard) aint a good thing to hear either.
I'll let others speak up that’s just my thoughts!!
Donny
 

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Welcome to our site; I'm sure you'll get a lot of suggestions on this.

Here's what I did; The GM 350 crate engine is a great deal at $1499 and I did see JEG'S had these w/free shipping just a few wks ago. I did the 260 hp w/ Holley 670 and it is sweat. I'd also just run your trans for a while. When you start rebuilding/along with head work you're heading in the wrong direction. Do you homework and work your plan. Hope this helps// Dale
 

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a .060 overbore is still a good bore, that makes it 362c.i.''
yes the freeze plug described is used by reman shops to tell if a engine was damamged by overheating the lil metal tag will fall off or it will turn colors
as stated all your accs will bolt up to the new motor, i run a 362 combo with no issues as far as overheating or anything else. as far as replacing one piston i had to do the same thing about 7yrs ago and as long as its the same brand ect ect you should be fine, i would have it balalnced while its apart it makes a big difference just my 2cents but hey what do i know - i run a wore out truck motor
 

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With the 60 over bore may over heat if you have AC. The engine that I have in my 81 would with the AC on at stop lights.
 

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Lucky???? Yeah. I'd think about a long block with a good warranty before going with this deal, UNLESS, it's just one "ya can't refuse". Also, ya gonna do the swap yourself, or have a mech do it fur ya?? You're gonna have a "good" time with a 350 over a 305 iffin' you're runnin' ECM. Ya gonna hafta change that to a 350 ECM for the q-jet and distro. OR, get away from the stock and use a non-ECM q-jet and distro.

AND, it's good to see ya on hear!!! (Yes, I know him).
 

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Jalapeno - check out this thread and photo bucket pics. I did your swap on my 85. Also kept the 200c and had it rebuilt. Love it, runs great!
 

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I don't see the logic of spending money on a block that has been bored so big. There are too many great deals available for crate motors that arrive new with a warrantee. Just say "no" and walk away.
 

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I too am not particularly keen on the overbore, a sonic test would be a good recommendation. If the piston skirt on #2 was damaged, one has to ask what damaged the skirt? remember the only thing the skirt is in contact with is the bore and a damaged skirt is fairly likely to scratch or scuff a cylinder, which could require cleaning up the bore with a hone.

I dont like replacing individual pistons without rebalancing the system. Nor would I use a 305 head on the 350.

Truely by the time a sonic test is done, might as well have the block magnafluxed while its all apart, so then the new piston is installed, the rotating assembly is balanced then having the valve job done on the 305 heads. Add to that the cost of the short from the guy....I really think you should be looking at that crate mentioned earlier.
 

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if you arnt after more power just have your 305 rebuilt. at 60 over there is not much life left in it and if the cooling system isnt up to it it may well run hot.personally i never run one over 40.also the early motor will have the dipstick on the wrong side of the engine, on a 75 it is on the driver side and is covered up by the exhaust manifold.
 
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