350 L-98 block questions
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
350 L-98 block questions
I've got a used L-98 block for free (still have to go and pick it up) and I
still haven't decided if I should use it for my motor build.
I have a few questions:
1. Are all L-98 blocks 2 bolt?
2. How hard is it to prepare block for 4-bolt splayed main caps?
4. Would it be better to find 4-bolt block?
still haven't decided if I should use it for my motor build.
I have a few questions:
1. Are all L-98 blocks 2 bolt?
2. How hard is it to prepare block for 4-bolt splayed main caps?
4. Would it be better to find 4-bolt block?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
If it is really an L98, then it is a 2 bolt block. There is no other difference than, possibly the main cap bolts, between the L98 and other 350 engine blocks, so maybe what you've found isn't actually an L98. Other items worth noting, depending on the year, L98 and non-L98s, can have one or two piece rear main seals, left or right dipstick openings, and be for OE roller cams, or not. Depending on your ultimate usage, 4 bolt mains, while desirable, aren't needed as often as thought. Changing main caps is a machine shop operation. At the very least the engine has to be line bored when the original main caps are replaced.
RACE ON!!!
RACE ON!!!
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
L-98
1. in 85, the block was a standard 'ol 2 bolt main small block with forged pistons, L/H dipstick, 2 piece seal, flat tappet cam.
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
Last edited by coupeguy2001; Feb 17, 2008 at 10:45 PM.
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
1. in 85, the block was a standard 'ol 2 bolt main small block with forged pistons, L/H dipstick, 2 piece seal, flat tappet cam.
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
Racer
Joined: Sep 2005
Posts: 484
Likes: 0
From: Germany
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
1. in 85, the block was a standard 'ol 2 bolt main small block with forged pistons, L/H dipstick, 2 piece seal, flat tappet cam.
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
1989 did eliminate the cold start injector.
Advanced
Joined: Feb 2005
Posts: 92
Likes: 0
From: Henderson Nv
I used my '87 L98 block. I had 4 bolt main splayed caps installed by my motor guy. The price of the caps, ARP bolts and line bored was a little over 600.00 bucks. I think it was worth it. Here are a couple of pictures.
Doug
Doug
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
Here is the whole story:
I'm still in planning phase. My first thought was to find 400 block and
build that, but it seems that finding one could be difficult task.
So, I can say that I'll go with 350 block for sure.
In a few sentences, here is what I want;
I want to build engine that will be rev happy (read 7500 redline).
It has to be N/A engine at first, but I'll go with all forged internals and
max 10.5:1 CR so maybe later I could add SC. I know that it's high CR
for boost but if I ever add SC it won't be more that 6PSI max boost.
I would like to get as much as possible out of that engine, so 383 stroker
seems good, but I'm not sure how much strokers like high rpms.
I know that there are a lot of factors to consider, but I'd like to set my
mind about what block and what CI to go with.
Please feel free to input all your thoughts and advices.
I'm still in planning phase. My first thought was to find 400 block and
build that, but it seems that finding one could be difficult task.
So, I can say that I'll go with 350 block for sure.
In a few sentences, here is what I want;
I want to build engine that will be rev happy (read 7500 redline).
It has to be N/A engine at first, but I'll go with all forged internals and
max 10.5:1 CR so maybe later I could add SC. I know that it's high CR
for boost but if I ever add SC it won't be more that 6PSI max boost.
I would like to get as much as possible out of that engine, so 383 stroker
seems good, but I'm not sure how much strokers like high rpms.
I know that there are a lot of factors to consider, but I'd like to set my
mind about what block and what CI to go with.
Please feel free to input all your thoughts and advices.
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Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
With your goals finding or building a 4 bolt block makes sense. I would stay with a 355 on a base 350 block. You can go with 10:1 but 10.5:1 does seem high for a SC engine. Just my .02
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by coupeguy2001
1. in 85, the block was a standard 'ol 2 bolt main small block with forged pistons, L/H dipstick, 2 piece seal, flat tappet cam.
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
2. in 86, it was the first year for a R/H dipstick and one piece rear main seal, 2 bolt mains, flat tappet cam, pan reinforcement strips, cast iron heads.
86 1/2.......aluminum heads
3. in '87, roller cam with cam retainer, roller lifters, engine block drilled for lifter spider, 1 piece seal, 2 bolt mains, R/H dipstick, center bolt heads, guided rockers, oil pan reinforcement strips.
4. in '88 Roller cam with cam retainer, drilled for lifter spider,1 piece rear seal, R/H dipstick, 4 bolt mains, center bolt aluminum heads, guided rockers, oil pan reinforcement strips
5. In '89 same as '88 except for 113 D port heads, elimination of the 9th injector.
6. In '90, same as '89 except elimination of maf sensor
7. In '91, same as '90
2. Not the first year of the right side dipstick. See no. 1.
3. OK. No changes to the block after 1987.
4. NO 4 bolt mains.
5. The BLOCK doesn't change because of the heads.
6. No change in the block.
All Gen I (L83 & L98) C4 engine blocks have right side dipsticks and two bolt main bearing caps. In 1986 the rear main seal was changed from the 1955 and up two piece style, to a one piece seal. 1987 was the first year the bosses for the roller lifter retainer spider were cast into the valley.
RACE ON!!!
