L20b rebuild

[80daterpillar]

I know its been asked a billion times, just tough to find it all in one place...

 

I'm going to pull and rebuild (giving up on the swap, too much work, and just not as nostalgic!) my l20b in my 80 720 (w58 open).

 

I can just get a kit and rebuild it, but I'm a guy that likes a little more for my money.

 

So, I'm looking for no (or low) extra cost rebuild options that I'd have to do anyway... I'm going to do assembly etc myself and will have machine work done, just looking for an easy cheap way to squeeze out a few more beans out of this motor. Seriously, don't want to build a race motor guys!!! ;)

 

I believe I read mike talking about throwing in l18 pistons to get +1 to CR, maybe a little cam regrind?

 

Necessary info:

 

1980 l20b non married mani's

w58, open chamber (I believe)

weber 32/36

EGR delete

Daily driver

 

I don't really want to incur the cost of a new manifold, carbs, header, as I just got the weber.

 

Whaddya got?

[wayno]

I would find another L20b block/head to rebuild, that way the truck can be driven till the engine is ready, and you would be able to pick what you want, even go the route of an LZ23 like I did, with an early head, but that would mean you would need a square port exhaust manifold, but your intake is already divorced, so that is no big deal.

I don't like vehicles that don't move under there own power, but that is just me.

[80daterpillar]

I would find another L20b block/head to rebuild, that way the truck can be driven till the engine is ready, and you would be able to pick what you want, even go the route of an LZ23 like I did, with an early head, but that would mean you would need a square port exhaust manifold, but your intake is already divorced, so that is no big deal.

I don't like vehicles that don't move under there own power, but that is just me.

 

Should've mentioned... already in the non-running stage

[wayno]

Should've mentioned... already in the non-running stage

 

I should likely have already known this from the other thread already, sometimes I don't remember things.

[tr8er]

I put in flat top pistons, performance crank, new rings, seals, none of it was really amazing. Weber, electric ignition, good gap, and good compression. Those things made a huge difference.

[banzai510(hainz)]

I would NOT put FLattops in a L20!!!!!!!!!!!!

[bonvo]

from what ive been reading its the l18 pistons you want there dished but a much shallower dish then the l20 pistons bump your compression up to 9,2:1 if im remembering right

[80daterpillar]

I got a lead on a rebuilt u67 head for about 200$. Or I can reuse mine after inspection of course. Anyone else know whether the l18 pistons are worth it? I have about 140k on the motor and if I can reuse parts I will. I'm just trying to get it all on paper so I know what to get/do/tell the machinist.

[bonvo]

well according to my fsm the stock compression for an l20 is 8.1:1 so jumping to 9.2:1 would be a very nice gain in performance. should asl still be able to use 87 octaine as for the u67 i say go for it its the head that troy ermish likes and it comes stock with nice big ports

[80daterpillar]

Just to please to photo guys...

 

nothing to brag about!

 

:thumbup:

 

[banzai510(hainz)]

clean up the engine bay. be looking good

 

 

look good now already nice and simple

[80daterpillar]

Well, fAck it! 175-180lbs dry, I'll take my chances and save the money for my 4.3

 

Now, on to getting head!