86ltrain

I'm looking to swap a 350 from my old pickup (newer 90's block) into my 84 Z28 / 700r4....It is currently bolted to a 700r4 as well, will it be a direct bolt in? I'm assuming yes but want to make sure...as long as the flexplate is the same size all is ok? I'm thinking it has the larger flex but won't know until I remove it. I had intended on tweaking my L69 but after removing the oil pan I found somewhere around .040 - .050 endplay. The rearmost thin part of the crank the thrust bearing runs on is REALLY wore. Didn't see that one coming, only 63K miles...

Night rider327

iTrader: (13)

You will need the flexplate from the newer 1 pc rms engine.

The two intakes are diff as well and of course you know the valve covers are diff.

86ltrain

I should have mentioned that it already has older style heads on it...am I right in thinking that all 350's are internally balanced? Only the 400's are external?

86ltrain

Just answered my own question...Only 400 needs external balance...Does anyone on here know if all truck engines use the larger flexplate? I don't have the engine out and want to get my parts ready to go.

jmd

iTrader: (4)

Any truck 86 and newer will have a 168 tooth flexplate / flyheel.

If your 84 Z28 has the original 153 tooth flexplate and starter, the starter bolts will be in line (not diagonal,) and perpendicular with the flexplate. And they will be 2 different lengths. If you have that, all you need is:

A flexplate for an 86-97 F-body. It will match the starter, and match the crank and balance of the new engine. It will bolt to the 84 700-R4 converter.
The flexplate bolts in the new engine can be re-used.

86ltrain

Never occurred to me but that makes the most sense...then I can reuse my starter rather than get one for the 168 tooth plate. Thanks

novaderrik

is that newer block drilled for the mechanical fuel pump?

bigal55

iTrader: (1)

Before you put the "new" engine in, you may want to look at the reason for the crank thrust surface wear. Check your torque convertor for ballooning. With an automatic, there should really be no forces pushing the crank forward unlike a manual trans that has clutch pressure plate forces whenever you press the clutch pedal. Just something to check so you don't end up with the same results on the "new" engine. Something to check, it's easy enough! GL with the swap!

86ltrain

You bring up a valid point, what do you mean by "ballooning"? Would it be obvious just by looking at the convertor? And yes, It is drilled for a mechanical pump, I had one installed in its previous application. Thanks for the input everyone...

Ozz1967

iTrader: (4)

double check this before you install it otherwise you will be dropping the tank to install an in-tank fuel pump like I did. Twas...unexpected to have mounting points but not have it drilled all the way through. The cost of the machine work to put a mechanical pump in for me was nearly the same as buying an in-tank pump and going that route.