The small block thread, Zach rebuilds a 350 (maybe 383 one day soon) Options

[VaccaRabite]

This thread will document my teardown and rebuild of a Chevy 350 small block engine.

This may be old hat to many of you, but I have never done it before and figured some of you may be interested as well, especially if you are considering putting one of these into your 914.

The engine that I am starting with is a 4 bolt main block truck engine out of a 1985 Chevy K20 3/4 ton pickup. I am not yet sure what the engine will be when I am done with it. I want to build a 383 stroker engine. But, the parts for this engine are so nice that I may stick with stock displacement and just go with better heads and intake. The heads and intake have all the smog stuff on them, so they are not going to be used.

Enough with words. Time for pictures.

First, lay out your tools on the rear trunk of your old Porsche. Only the finest work jacket will do to keep the paint scratches to a minimum.
(IMG:http://www.914world.com/bbs2/uploads_offsite/farm6.static.flickr.com-1435-1292897321.1.jpg)
For tear down you need 4 wrench sizes (all inch sizes). 3/8, 7/16, 9/16, and 5/8th. You will want to have these sizes in deep sockets and wrenches. You will want to have at least one breaker bar to break torque on most of the 9/16 and 5/8 bolts. Also a rubber hammer, pry bar, and scraper will be needed.

The beast:
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This is the engine that I am going to be tearing down. It was pulled out of the donor truck Dec 10th and mounted on the engine stand the next day. Don't even think of trying to do this without an engine stand. This 1000 pound stand only cost $50, and it is money well spent. Fair bet my 914 has a little bit of engine envy right now....

Valve covers first.
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Valve covers need to come off first, as they impinge removing the intake. One off in the picture above. You need a 7/16 deep socket to take off the nuts that hold the valve covers on. Lots of sealant was used here.

Valve covers, carb and intake are off.
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(IMG:http://www.914world.com/bbs2/uploads_offsite/farm6.static.flickr.com-1435-1292897324.5.jpg)
Pretty easy so far. Time to go for the heads. The rods going into the block are all the push rods. They come up from the cam and operate the valves. The orange ball of fire is my heater. 70K BTU of warmth to stave off the cold, even with the garage door open. I even had to take off my warm overalls, as I started sweating with the heater and the overalls both. The intake was attached with 9/16th bolts. There was considerable sealant used, and getting the intake off was difficult. I ended up using a pry bar to get it started, and hold it up enough to get my fingers in there to pull the rest off.

First head is off.
(IMG:http://www.914world.com/bbs2/uploads_offsite/farm6.static.flickr.com-1435-1292897325.6.jpg)
This is the point where I had to do some soul searching. It was pristine! The cylinder walls look like they were just done. There was no carbon ring at the top of the cylinders, which is common for an engine with miles on it. The PO of the donor truck said the engine had been rebuilt 4000 miles ago. But given the condition of the truck and the electrical system (the spark plugs were rusted and fell apart on removal) I had my doubts. Now, though... it took a fair deal of will power to not just button the engine back up again and put new heads and intakes on it. But, I am a stubborn man at times... I am going to rebuild this engine, darn it! This is how I learn. The heads bolts were 5/8s and were heavily torqued. I needed a breaker bar to get them started.

With the heads off I took off the pulley and damper. The damper was a PAIN to get off. Lots of prying with the pry bar all over to keep it from cocking. One of those things where I probably should have used a puller, but I did not have one the right size or the desire to go and get one.

to be continued....

[messix]

the 383 build reuses the rods.

a 383 kit has the 3.75 crank and pistons that have the correct wrist pin hight for the 3.75 crank.

i doubt the p/o line bored that block, most low preformance rebuilds don't line bore.

the vortec heads will make excelent torque with an rv cam.
dollar-dollar these heads will be the best investment for power over the old heads. [read up on them] also these heads take a different intake mounting design [bolt holes are different] so make your mind up on these early before buying a intake.

shorter advertized duration with some good lift [450-475] will do good.


the ls motors are awesome but you loose the k.i.s.s for a truck like that. and there is no way you could be concerned with fuel economy with that truck!

a mild 383 built right will have big block type torque and great power, expect about 400-450 ft lbs from 2500 -3500rpm.

[ArtechnikA]

a mild 383 built right will have big block type torque and great power, expect about 400-450 ft lbs from 2500 -3500rpm.

...but too much can be as bad as too little.
More torque than the driveline is built for leads to the path of more expensive upgrades. Bigger transmission - bigger cooling to reject the additional heat of more power and driveline. Bigger driveshaft. Bigger 3rd member.

The weakest link is always - something. I prefer it be the engine making less power than the driveline can handle. This doesn't leave you parked on the shoulder of the big hill during a tow wondering how you're going to replace the rear axle or driveshaft... (Which can itself go to hell in a handbasket, because if the driveline breaks, you better have loads of confidence in your E-Brake/Parking Brake, because 'Park' in the transmission ain't gonna do diddly...)

If you're just whittling into the safety margin, that's one thing, but going over the line foreshadows nasty consequences. Yeah, I know lots of guys still run 901/914 gearboxes behind SBC's in 914's - but they are for playing, and trucks are for working... (E.g. - I'm pretty sure that cubic yard of topsoil I hauled home in the half-ton Titan was more than the 1000-lb payload it's rated for...)

[messix]

a mild 383 built right will have big block type torque and great power, expect about 400-450 ft lbs from 2500 -3500rpm.

...but too much can be as bad as too little.
More torque than the driveline is built for leads to the path of more expensive upgrades. Bigger transmission - bigger cooling to reject the additional heat of more power and driveline. Bigger driveshaft. Bigger 3rd member.

The weakest link is always - something. I prefer it be the engine making less power than the driveline can handle. This doesn't leave you parked on the shoulder of the big hill during a tow wondering how you're going to replace the rear axle or driveshaft... (Which can itself go to hell in a handbasket, because if the driveline breaks, you better have loads of confidence in your E-Brake/Parking Brake, because 'Park' in the transmission ain't gonna do diddly...)

If you're just whittling into the safety margin, that's one thing, but going over the line foreshadows nasty consequences. Yeah, I know lots of guys still run 901/914 gearboxes behind SBC's in 914's - but they are for playing, and trucks are for working... (E.g. - I'm pretty sure that cubic yard of topsoil I hauled home in the half-ton Titan was more than the 1000-lb payload it's rated for...)

well coming from some one that bought a ..... foriegn "full size pick up" (IMG:style_emoticons/default/poke.gif) (IMG:style_emoticons/default/slap.gif) .....

the engine and tranny he got came out of a real 'merican 1 ton pick up!!!!

and true the only weak link here would be the stock unrebuilt tranny, but those are very inexpensive as exchange rebuilds [around here less than $1,000 for a 700r4]

the rest of the drive train... have you looked at the truck? it's a military truck!!! he could beat the living crap out of that and not hurt the drive train!

and i wouldn't get to hung up on making low rpm power wioth the stock axles 'cause those are most like around 4.88 or bigger gears.
freeway running even with tall tires will be around 2500 rpm or so.

[ArtechnikA]

well coming from some one that bought a ..... foriegn "full size pick up"

Yes, from the distant shores of Kentucky...

the rest of the drive train... have you looked at the truck? it's a military truck!!! he could beat the living crap out of that and not hurt the drive train!

I saw that. But as this is a 'general-interest 914' thread, it was a general-interest comment.

And yes, I have built an engine so well it broke the transmission...