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Rebuilding an '87 350

MarkD

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MarkD Senior Enthusiast

MarkD

Posted
Posted

We will be puting it in an '85(?) Chevy truck.

 

Any advice of anything specific to look for, replace?

 

He is trying to get out as cheap as possible with a reliable motor.

 

My advice so far is to replace:

 

All bearing surfaces

Full gasket/seal kit

Have crank journals polished

Magnaflux block

New cam/lifter/valvespring kit

New piston rings

New Wrist pins

Get rid of fuel injection, get 600cfm carb and aluminum intake

 

 

Any advice?

americanmuscleman Enthusiast

americanmuscleman

Posted
Posted

Sounds like a good plan. It wouldn't be hard to keep the TBI injection if you wanted to.

 

While you have it apart, I'd consider having it bored .030" to make it like new again. Just get 30-over pistons for it.

 

I'd also look at the distributor. If you can reuse it since its advanced electronically, I would check to make sure the shaft doesn't have too much play in it.

 

Depending on how many miles you have on the motor, you might look at having the valves and valve seats resurfaced.

 

I may be stating the obvious, but I'd make sure you put new valve seals in and a new timing chain and gears. I would also replace the oil pump while you have it apart.

 

Assuming its all put together properly, you'll have a great motor.

MarkD Senior Enthusiast

MarkD

Posted
  • Author
Posted

My tendency is to go overboard when building a motor.

 

I was thinking about new pistons, but trying to keep him from spending that $250.

 

Yeah, I forgot about the oil pump. I mentioned it to him, but forgot to list it.

 

I haven't seen the distributor, the motor was on a crate when I saw it. I haven't been under the hood of the truck yet.

 

Good idea on the heads, I think he may go for a valve job depending on the block machining costs.

 

Below are guesstimated prices, any ideas of where to spend more/less money?

 

All bearing surfaces - $150

Full gasket/seal kit - $100

Have crank journals polished - $ 50

Magnaflux block - $ 50

New cam/lifter/valvespring kit - $150

New piston rings - $ 45

New Wrist pins - $ 50

Get rid of fuel injection

get 600cfm carb - $200

aluminum intake - $100

Oil Pump - $ 50

 

 

Total of $950 without pistons or headwork!

MarkD Senior Enthusiast

MarkD

Posted
  • Author
Posted

Does anyone know if '91 z28 heads will fit an '87 Blazer block? Both are 350 SBC, both have iron heads.

 

Would a special intake be required?

americanmuscleman Enthusiast

americanmuscleman

Posted
Posted

I haven't visited the board lately to see your question.

 

91' TPI heads will bolt up to an 87' 350 block. The chamber volumes are obviously a lot smaller on the TPI heads, and you might have to modify the intake manifold runners to match the TPI heads. All the mounting holes and exhaust ports will match up fine.

 

As an idea if you want to gain a little power, you might throw on a set of Vortec heads with a Vortec/Carb intake.

 

As far as pricing goes, on a project like this, I always take the price I expect to pay, and double it. Every major project seems to have its setbacks and unexpected problems. Your pricing sounds pretty low. I imagine you'll spend quite a bit more than your guessing. Something closer to $1500 to complete your list.

 

Also you might want to run a 650 carb. Getting a decent carb for $200 is going to be hard too.

 

Good luck with the project!

MarkD Senior Enthusiast

MarkD

Posted
  • Author
Posted

My neighbor (owner of the motor) was hopeing to do the "minimum" or pretty close.

 

My response was that it would be a wast of time to put a gasket set on a 80k mile 350. At the very least new bearings, oil pump and lifters. Along with some machine work.

 

The reason for the carb is the truck came with an Fuel Inj. 305. I can't imagine the computer working on a 350. He may even consider a 2 bbl.

americanmuscleman Enthusiast

americanmuscleman

Posted
Posted

Actually, if the motor is running great, with only 80k on it, I bet replacing the gaskets will allow it to keep on going for a long time. TBI 350's are really good motors from the factory, and if taken care of can last 200k+ without a rebuild. If the motor ran great when he pulled it, I wouldn't tear it apart unless it leaks or you want to build it up. The stock bearings and seals should be fine at 80k. Even the timing chain

 

I've got 117k on mine now and put 95k on my previous one. Both run excellent. I've got a few friends with some high miles on some too. 235k on one, all stock. 197k on another, all stock. 187k on another. None have had any major problems. I actually don't know anyone who has had major problems with a TBI 350. I popped a head gasket a few months back on my current motor, but thats related to the fact that I put aluminum heads on it and copper racing head gaskets.

 

A TBI 305 intake and throttle body system is exactly the same as a TBI 350 one, with the exceptions being, the injectors are larger in the 350 throttle body, and the computer calibrations are different. You could install injectors and a chip from a TBI 350, and it would run great.

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