Will a ZZ4 shortblock work??
Thread Starter
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Could someone tell me if a ZZ4 shortblock will work in my 89 coupe? If it will work will all the parts( Heads, oil pan,Distributor,Intake manifold, off my L-98 I have now bolt right up, or will I have to modify some things. .Will I need a new chip burned if I just have the plenum and intake ported and add headers?.Thanks in advance.WW7
Last edited by WW7; Jan 4, 2009 at 03:26 PM.
Thread Starter
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Sorry I should have said ( the cam will be stock) .I have a friend in our car club that bought a ZZ4 short block for his Camaro last year and then wrecked it ,now wants to sell the block ( Cheap ).
Last edited by WW7; Jan 4, 2009 at 03:32 PM.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Should be no problem at all. You may want to have the engine balanced. I know....it is a GM brand new short block.....but they don't come from the factory balanced the way I would like it. If you want this to last....spend the extra $$ and have it balanced. You can check out one of my threads on balancing in the engine mod section.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
I am not that familar with the 89, but the ZZ4 block is a one piece rear seal. If your is not, you will need a new flex plate for an automatic.
Are you going to do all the work yourself? If you engine has a few miles on it, consider new timing chain and gears. Might freshen up the heads and have valve job (again if you have a few miles on the engine)....or go with a good set of aftermarket heads.
John
Are you going to do all the work yourself? If you engine has a few miles on it, consider new timing chain and gears. Might freshen up the heads and have valve job (again if you have a few miles on the engine)....or go with a good set of aftermarket heads.
John
Le Mans Master
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From: E. Amherst NY
Le Mans Master
Joined: Aug 2000
Posts: 8,838
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From: Australia
ZZ4 is crate motor version of L98 roller cam engine (w/4 bolt mains).
Need Vette water pump and balancer.
If all you are doing is swapping the block then no tune needed
As a note I ran the ZZ4 cam in my '89 without a tune and it ran fine.
Ran 'better" with minor tune but than was mainly adjustments to spark timing because '89 has very aggressive spark advance
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Le Mans Master
Joined: Jan 2002
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From: Edmonton AB
Perhaps the ZZ4 short block is a straight swap for an '89 L98. But
some things to consider are as follows.
The OP's '89 L98 has dished pistons. The ZZ4 he is considering has
flattop pistons with four valve reliefs.
has been appropriately balanced. The OP's existing flywheel/flexplate
may or may not be suitable - depending on whether the bob weight
for the '89 was the same as for the ZZ4. A new ZZ4 FW/FP will be
factory balanced to be within an OEM tolerance. This may be
acceptable.
If the OP proceeds with the purchase and considers balancing the
engine, before allowing work to begin he should get assurances
from the shop owner that the hypereutectic pistons can be safely
removed from the rods without damage (and a written statement
about what the shop will do to make things right if a piston is
cracked during removal.)
.
some things to consider are as follows.
The OP's '89 L98 has dished pistons. The ZZ4 he is considering has
flattop pistons with four valve reliefs.
Courtesy: Pace Performance
10159436 - ZZ4/LT1 High Performance Piston (Standard)
Parsed from an '03 post by Dr. Evil plus specifications from CAC10159436 - ZZ4/LT1 High Performance Piston (Standard)
OEM static compression changed from 9.5:1 in '89 to
10.25:1 in '90 as a consequence of a change from dished
to flattop pistons. The flattop pistons are reportedly lighter.
This increase in static compression was accompanied by
a more modest camshaft profile (which may have had the
effect of compensating by reducing dynamic compression.)
The 1-pc rear mainseal ZZ4 crank requires a flywheel/flexplate that10.25:1 in '90 as a consequence of a change from dished
to flattop pistons. The flattop pistons are reportedly lighter.
This increase in static compression was accompanied by
a more modest camshaft profile (which may have had the
effect of compensating by reducing dynamic compression.)
has been appropriately balanced. The OP's existing flywheel/flexplate
may or may not be suitable - depending on whether the bob weight
for the '89 was the same as for the ZZ4. A new ZZ4 FW/FP will be
factory balanced to be within an OEM tolerance. This may be
acceptable.
If the OP proceeds with the purchase and considers balancing the
engine, before allowing work to begin he should get assurances
from the shop owner that the hypereutectic pistons can be safely
removed from the rods without damage (and a written statement
about what the shop will do to make things right if a piston is
cracked during removal.)
.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
OEM static compression changed from 9.5:1 in '89 to10.25:1 in '90 as a consequence of a change from dished
to flattop pistons. This increase in static compression was accompanied by a more modest camshaft profile (which may have had the effect of compensating by reducing dynamic compression.)
The 1-pc rear mainseal ZZ4 crank requires a flywheel/flexplate that
has been appropriately balanced. The OP's existing flywheel/flexplate
may or may not be suitable .
to flattop pistons. This increase in static compression was accompanied by a more modest camshaft profile (which may have had the effect of compensating by reducing dynamic compression.)
The 1-pc rear mainseal ZZ4 crank requires a flywheel/flexplate that
has been appropriately balanced. The OP's existing flywheel/flexplate
may or may not be suitable .
GM only list one 153 tooth flexplate (#14088765 ) for 1 pce seal cranks
"Technical Notes:
Flexplate is for 1986 and up. Engines before 1986 us a two-piece rear seal. The bolt circle on pre-1986 crankshafts is 3.58” in diameter.
For 1986 and later crankshafts the bolt circle is 3.00”.
If your engine has a crankshaft with a one-piece rear seal, you must use a flywheel (or flexplate) with a 3.00” bolt pattern and a counterweighted flywheel for proper engine balance."
Thread Starter
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Lots of great info there guys, Thanks. I was going to replace most moving parts instead of using whats on my L98,just wasn't sure if distributor and heads would work. Heads will be getting complete rebuild,What cam would you suggest if I don't go with stock.If I get a different more aggresive cam at what point will I have to get higher pound injectors, Im running 22 lb bosch now? What I would like to have when done is about 300 hp, If I have my Plenum, runners and base ported and run a set of headers what roller cam would I need to get to this HP.I was not going to reuse my L98 roller cam anyways so might as well go for a little more if I don't have to change a lot of other things because of it.My L98 has 124,000 on it so Im a little leary of using most of the moving parts. John, I will be doing the work myself with a friends help,I can use my friends lift and shop and just give him something for the use? To old to be laying on the ground.. Thanks...WW
Last edited by WW7; Jan 4, 2009 at 08:59 PM.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
,What cam would you suggest if I don't go with stock.If I get a different more aggresive cam at what point will I have to get higher pound injectors, Im running 22 lb bosch now? What I would like to have when done is about 300 hp, If I have my Plenum, runners and base ported and run a set of headers what roller cam would I need to get to this HP..... Im a little leary of using most of the moving parts.
There are better cam BUT the factory got 355Hp with a carb;
I calc mine was 315Hp ; big tubes / headers / ported plenum / siamised base on a 100K '89 engine.
Last edited by rodj; Jan 31, 2009 at 11:46 PM.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Do you have to pass SMOG where you are? If so then go with something like the Linenfelter 74211, it will pass SMOG without a problem. The 74219 can pass.....but you have to have chip and everything else dead on. Your injectors should be able to handle your conversion.
As far as HP, I was dyno'd at 284 RWHP with stock bottom end (cam/pistons) for the 85 L98 with AFR 180 heads, 1.5 & 1.6 RR, SuperRam intake, runners & plenum and a little exhaust work (no headers). The 284 RWHP is close to 350 at the crank. That was with 320,000 miles on the engine. I haven't dyno'd the ZZ4 combination yet to know what I ended up with.
If you go with RR with the cam with a higher lift, and headers you could be close to your 300 HP. A good set of aftermarket heads would push you over your goal. Your restriction may be the intake assembly even with the porting.
As far as HP, I was dyno'd at 284 RWHP with stock bottom end (cam/pistons) for the 85 L98 with AFR 180 heads, 1.5 & 1.6 RR, SuperRam intake, runners & plenum and a little exhaust work (no headers). The 284 RWHP is close to 350 at the crank. That was with 320,000 miles on the engine. I haven't dyno'd the ZZ4 combination yet to know what I ended up with.
If you go with RR with the cam with a higher lift, and headers you could be close to your 300 HP. A good set of aftermarket heads would push you over your goal. Your restriction may be the intake assembly even with the porting.
