1990 L98 Engine Block
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Joined: Mar 2007
Posts: 86
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From: Atlanta Ga
1990 L98 Engine Block
I have a 90 Vette ( i know nothing about them) and it may need a new block due to a machineing error. What should i do? Where can i get one and how much will it cost me?
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Gm sells them new. I believe summit racing does as well. If you need a used block to machine , they are quite common and easy to find. Start asking local garages what they have in the junk pile. I normally find them there. Some are happy to give them away, just to clean the clutter.
Thread Starter
Advanced
Joined: Mar 2007
Posts: 86
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From: Atlanta Ga
I'm in Atlanta! Should i use the casting numbers to cross reference when purchasing a new block? I know chevy made tons of 350's and i don't want to end up with a truck block unless it will work! Can anyone answer the question, "is it a 2 bolt or 4 bolt main?" I think the block it currently has is a 2 bolt, but i'm not sure!! Do you have the link for GM or Summit to find the block? i think its a roller, is that right? Again, its a 1990
Racer
Joined: Dec 2006
Posts: 292
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Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
A bare 4-bolt block that may be of interest is p/n #10105123.
Currently about $700 at GMPartsDirect
Currently about $700 at GMPartsDirect
DESCRIPTION: 350ci Bare Block
This engine block is used in 1986-99 Gen I heavy-duty applications. It has 4.00" diameter cylinder bores and four-bolt main bearing caps. This block is machined for a one-piece rear crankshaft seal. (Does not include rear seal or adaptor.) These blocks weigh 181lbs. Technical Notes: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for hydraulic roller and flat tappets. Crankshafts with two-piece seals can be installed with adapter P/N 10051118. (Block casting P/N 10243880 or 14093638.)
For $450 more, you could get a fitted shortblock. Take a look at This engine block is used in 1986-99 Gen I heavy-duty applications. It has 4.00" diameter cylinder bores and four-bolt main bearing caps. This block is machined for a one-piece rear crankshaft seal. (Does not include rear seal or adaptor.) These blocks weigh 181lbs. Technical Notes: Cylinder wall thickness is the same as current production engines. The lifter valley is machined for hydraulic roller and flat tappets. Crankshafts with two-piece seals can be installed with adapter P/N 10051118. (Block casting P/N 10243880 or 14093638.)
p/n #12556121
L31 350 SB Chevrolet Short Block
Manufacturer: GM Performance Parts
Block : Cast Iron 4 bolt mains
Rear Main Seal Type : 1 - Piece
Crankshaft : Nodular Iron
Stroke (inches) : 3.480"
Piston Description : Cast Dish 4VR (-13cc)
Compression Ratio : 9.0:1 w/ 64cc heads
Compression Ratio : 8.3:1 w/ 72cc heads
Factory Roller Cam Compatible
.
L31 350 SB Chevrolet Short Block
Manufacturer: GM Performance Parts
Block : Cast Iron 4 bolt mains
Rear Main Seal Type : 1 - Piece
Crankshaft : Nodular Iron
Stroke (inches) : 3.480"
Piston Description : Cast Dish 4VR (-13cc)
Compression Ratio : 9.0:1 w/ 64cc heads
Compression Ratio : 8.3:1 w/ 72cc heads
Factory Roller Cam Compatible
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
12510735 - L98/L05 350 Short Block Assembly 1 Piece Rear main,2 Bolt main, Roller Cam Provisions
Factory replacement shortblock for the following vehicles:
For 1990 - 1993 Caprice,1990-1993 Cadillac Fleetwood Brougham, 1992 - 1993 Buick Roadmaster, 1992 Olds. Custom Cruiser With 5.7L (LO5-7) 1990-1992 Camaro, Firebird & Corvette With 5.7L (L98-8).
Also a great shortblock to build a mild performance engine from!
This is the same shortblock our 12513151 crate engine is built from.
Engine Specs:
1986-2000 type 2 bolt main 1 piece crankshaft seal block with factory roller cam provisions
( NO MECHANICAL FUEL PUMP PROVISION)
Nodular iron crankshaft
Powdered metal Connecting rods
Flat top hyper- eutectic pistons
.
Factory replacement shortblock for the following vehicles:
For 1990 - 1993 Caprice,1990-1993 Cadillac Fleetwood Brougham, 1992 - 1993 Buick Roadmaster, 1992 Olds. Custom Cruiser With 5.7L (LO5-7) 1990-1992 Camaro, Firebird & Corvette With 5.7L (L98-8).
Also a great shortblock to build a mild performance engine from!
This is the same shortblock our 12513151 crate engine is built from.
Engine Specs:
1986-2000 type 2 bolt main 1 piece crankshaft seal block with factory roller cam provisions
( NO MECHANICAL FUEL PUMP PROVISION)
Nodular iron crankshaft
Powdered metal Connecting rods
Flat top hyper- eutectic pistons
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Burning Brakes
Joined: Aug 2005
Posts: 1,172
Likes: 9
From: '88 TPI L98/HotCam Powell, Ohio
Dang Slalom I thought I found a good price. :o Maybe the shipping would have equaled it out....yeah that's how I can rationalize it. 
I would have bought the 4 bolt version but the class I'm running won't let me go with a 4 bolt without considering it an engine swap. This new block will give me time to build the original the RIGHT way and I won't miss any track time. It really is hard to believe how cheap these things are now.
I would have bought the 4 bolt version but the class I'm running won't let me go with a 4 bolt without considering it an engine swap. This new block will give me time to build the original the RIGHT way and I won't miss any track time. It really is hard to believe how cheap these things are now.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
I think you did well with your price - as you mentioned, that is the
price to your door. Other members have posted about how GMPD
prices on smaller items often come with significant shipping fees, this
may also be the case on bigger items.
For me, GMPD is a standard measure. Their site has photos and details.
They are also a forum supporter. If a member happens to find the
same item for less somewhere else, well, that's free enterprise at work.
BTW, I'd like to thank you for bringing the p/n #12510735 - L98/L05
350 Short Block Assembly to my attention, I was not aware of this
assembly until your post.
Makes it hard to consider salvage engines when these are available
for the price quoted.
Thanks,
Ken R.
.
price to your door. Other members have posted about how GMPD
prices on smaller items often come with significant shipping fees, this
may also be the case on bigger items.
For me, GMPD is a standard measure. Their site has photos and details.
They are also a forum supporter. If a member happens to find the
same item for less somewhere else, well, that's free enterprise at work.
BTW, I'd like to thank you for bringing the p/n #12510735 - L98/L05
350 Short Block Assembly to my attention, I was not aware of this
assembly until your post.
Makes it hard to consider salvage engines when these are available
for the price quoted.
Thanks,
Ken R.
.
Racer
Joined: Dec 2006
Posts: 292
Likes: 0
I do not like the idea of getting an answer over the phone and then later finding out the answer was wrong.
Racer
Joined: Dec 2006
Posts: 292
Likes: 0
Since I don't want to use a dual mass factory flywheel why would I need a VIN number to get such a basic question answered?
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
Racer
Joined: Dec 2006
Posts: 292
Likes: 0
The problem is if I choose to not use the factory dual mass but instead a neutral balanced flywheel, then the answer would be wrong.
How to they cope with custom applications? I still don't understand why they cannot list a short block as internal or external balance.
How to they cope with custom applications? I still don't understand why they cannot list a short block as internal or external balance.