I have found this engine for sale for $150. Any input or comments about dropping this one in my '86 (after a rebuild of course) are welcomed. The engine is disassembled and the owner said the cylinder walls are in great shape (only a small lip at the top). My tranny is the 700R.

 

It's a 350 block. Not much to say one way or another. Not a particularly great price, but not bad either; that seems to be near about the going rate.

You'll have to get a flex plate for a 2-piece rear main seal crank, and the dipstick will be on the driver's side, which will absolutely not work in your 86 if it has manifolds. Headers would of course be the cure, which you'll wnat anyway to take advantage of the increased flow which manifolds are already choking off with your LG4. They're one of the biggest reasons why those are so much weaker than some other 305s in the first place.

 

maybe this is a dumb question, but is the flex plate a big deal or a common thing?
this will be my first rebuild and engine swap

 

I did basically the same with my '83 (79 Z28 motor)

There are only 2 major problems if i remember correctly

1. With a T5 (not sure about auto), you need to drill a hole in the block for a 305 starter to mount to because a 350 starter is too big for the belhousing.

2. The dipstick is on the drivers side. The easiest way around this is to get some headers because the stock manifolds bolt to the heads right above the stick. OR you can carefully bend the tube (careful not to kink it) to come out from under the manifold and make a custom dipstick with a cable instead of a regular dipstick blade (like on my car. i know for a fact this is possible). If you install headers, don't worry about the dipstick.

 

A flex plate is a common thing, they aren't very exspensive. Summit has one from TCI for about $70. Are you just using the block or are you reusing most of the old parts?

 

I plan to use as many of the old parts as I can. I do not want to sink ALOT of money in it. BUT, I do not want to have a wimpy engine either. I hope to find a happy medium (decent power without a whole lot of expense). I plan on running headers so that will eliminate the dipstick problem. I guess "shorty" headers will be my best bet?

 

You'll want to get shorty headers unless you plan on running custom or dual exhaust. Are you building it yourself or having a shop rebuild it? Is this the first time you've rebuilt a motor?

 

Yes, this will be my first rebuild. I plan on doing as much as I can myself.

 

If you want the most performance out of the motor on a budget, here's a few things I would do. When you have the block at the machine shop, have it bored and honed w/ a deck plate and also have it line bored and honed. You'll need new pistons so I would reccomend TRW forged pistons (they're cheap) or some hypereuctic pistons (Keith Black makes good ones). You can stuff bigger valves in the heads for some more flow, and do some port work. Sitting Bull has a thread about porting 305 heads, but the same ideas apply to 350 heads. It's not hard to do and the gains are worth it. Since you will probably be reusing the rods, have them magnafluxed and shot peened (stress relieved) and get NEW rod bolts otherwise you're asking to for the old ones to break. I would reccomend the book How to build the Small Block Chevy, and also Max performance Chevy's on a budget. Another good book if you get into porting is by David Vizard, it's called something like Chevy Small Block Cylinder Heads, or something of that nature I can't remember exactly.

 

Another thought, those 78 350 heads are smog era heads. I'd reccomend getting a set of 305 heads (081 casting I think). Once they're ported they flow about the same as Vortecs. Another good thing about them is that they have 58cc combustion chambers which is good for performance. The also benefit greatly with 1.94/1.60 valves.

 

Again, this being my first rebuild, I hope this is an intelligent question. Can I have the heads on my LG4 ported and use them?

 

Yes you can use them. They are the same heads that I mentioned above that flow like vortechs after porting. When you have them rebuilt, have 1.94/1.60 valves put in them because the stock valves suck. I think they're like 1.84/1.46ish, they're terrible.

 

The increase in compression alone from the 58cc stock heads will make them better heads to use. The stock compression ratio of the 78 350 is like 8 to 1. They will probably flow only slightly less than the 350s from the 78 in stock form.

I had a 78 z28. It was a heavy car and I was able to run 15.3s at 91MPH in the quarter with an open differential 3.42 geared rear end and open circle RV cam (264 adv duration, .464 inch lift). That was with a 8 to 1 compression ratio. Something like the XE268 cam and 9.5 to 1 compression ratio and good exhaust should be fun to drive for very little money.

 

I too have basically the same engine (stock '79 Z28 motor)

I may be able to get some L69 heads.. would they be good for my 350?

 

The Z28 engine your looking at is 8.5:1 (72 cc heads)compression and isnt a very impressive piece like mentioned. The 58cc heads would be a good way to bump the compression up cheap but DO NOT go with flat top pistons plain jane stock dished pistons will do fine. The LG4 manifolds will work to point, the dipstick tube will have to be smashed a little and a dipstick will have to be cut and marked with 5 full quarts of oil in the engine.

Have fun!