Slo_240sx

iTrader: (17)

I know 98' blocks have confirmed oiling problems. I didnt know this until later on when I started studying LSx engines more. I have a 98' block I am building myself due to a spun rod bearing. Will a ported LS6 pump be sufficent enough to cure the 98' problem? I would hate to finish the engine only to spin another bearing. Any cures or tips for these 98' problems? Thanks!
-Alex

ineedashortblock

iTrader: (3)

Depends on your goals. Going to take it up to 7k often? Probaly not going to help with that ls6 oil pump. Taking it to the factory 6200? Then you should be fine.

777

iTrader: (21)

You have misinformation. The 98 block doesn't have an oiling problem. It's the stock oil pump. Simple fix is you get a ported ls6 oil pump (got mine from Texas Speed). The 98 block can't be bored out past .005" but that's about it. So you are good to go.

Put good bearings and rod bolts in it and you should be good to go to 7500rpms.

PREDATOR-Z

I do not quite agree on the 7500 rpm bit.
98 blocks have been revised to facilitate oiling passage functions, they were found to suffer from high rpm oil starvation on the crank and rod bearings.
Unless you are doing an all out race motor, then rebuilding your 98 should be fine.

98A4LS1

iTrader: (1)

^^^ I agree. Also, a stock GM L6 oil pump is sufficient for a street car to replace the '98 oil pump.

jdustu

iTrader: (2)

i didn't take any chances and went with a katech blueprinted ported and polished ls6 pump.....only a few bucks more than a new gm ls6 pump

DrkPhx

iTrader: (15)

Actually there's truth to what he posted. The early 97-98 LS1 blocks do have a different oiling system compared to the 99-up blocks. Even though it was slight, it was still significant enough for GM to change the design on the later blocks.

When looking at the back of the bare block you can clearly see the difference between the two. Looking at the lifter galley holes on the early block you can see they are flush with the block itself. On the later blocks the holes are located in a deep crossover "pocket" which is cast into the block (the early block galley holes were drilled). This allows much better oil flow from the left galley to the right to prevent oil starvation at high, sustained rpm's.

I found this link (excellent source of Gen III tech info) with some pictures to help out. Scroll down and you will see exactly what I'm talking about.

http://www.automotiverebuilder.com/ar/eb040538.htm

FWIW - I always ran 6 quarts of oil at the track to prevent oil starvation at WOT. If I didn't the oil pressure would drop dangerously low to around 20 psi because the oiling system simply couldn't flow the oil fast enough. A ported oil pump did little to change this.

BlkHwk

iTrader: (8)

I have a 98 block and the rear oil passage was ported to allow better flow to the opposite bank. The block is not here with me but I'll try and post up a pic later this week. I plan to run 6qts. in mine as well.

I have a melling HV oil pump for mine I just hope it clears the Rollmaster dual roller.

Slo_240sx

iTrader: (17)

Thanks for the response guys. I am using Clevite-77 P bearings and plan on using a Lingenfelter LS6 ported pump. Is that a good pump choice? All clearances have been checked and are within spec. Its going to be driven a couple of times a week with a F14 cam, not a big race engine, just a fast street car. How hard is it to port the rear of the block? Any other tips?
-Alex

Slo_240sx

iTrader: (17)

Bumpity for the night, I love the info on this site but absolutely hate how fast post move to page 2!

Davy_Baby9

iTrader: (23)

I would be very interested in pics also.

MiaSSmaro98

iTrader: (9)

pics will be nice i plan on rebuilding mines as well next year even tough it runs fine but remember its a 98 which will be turbo soon so cant risk nothing

Slo_240sx

iTrader: (17)

Any pics on the porting yet?

OJmobileII

iTrader: (3)

also interested in the pics.

i recently tried installing the Rollmaster Adjustable Dual Roller Timing Chain and the Melling HV/HP Pump. i couldnt find a way to make the pump clear the chain while still fitting under the front cover. i tried grinding down the part #'s which were on the chain side of the pump and more shimming but the setup would not work for me.

maybe u will have better luck, but take my advice and if it doesnt fit right away dont try modifying it to make it fit so u can still return it. i went with a ported LS6 pump.

Blktie8

iTrader: (1)

I Agree i went with Katech on my 2000 c5
Great pressure with the reliability of Katech

BlkHwk

iTrader: (8)

Just got back with the pics. Came out kinda fuzzy. I was told I should apply some sealer to make sure it seals.


We're gonna try the Melling pump tomorrow if we can't make it work I'll go with the LS6. I was afraid we were gonna have probs with it. Thanks for the info on prev. attempts @ intalling the Melling pump.

ssbodyman

I went with the LS6 ported oil pump on mine and it seems to work just fine. I run mine to 6800rpm's with no oil pressure loss so as long as your not looking to build a 600HP motor or doing auto cross where you are staying way up there in the rpm's for long periods or time, the 98 block should work just fine. Just my 2cents.

Slo_240sx

iTrader: (17)

Thats a nice looking port job. Did you have a machine shop do that or did you take a dremel to it? How deep is it? looks about 3/8"?

smokin t/a 600

hey alex what's up, this is kevin with the black SS. I came to your shop a week ago cause I broke my rearend and am doing heads and cam....I ended up going with monkey wrench to do the install...we should go cruisin some time, i will have the car back in a few weeks.

BlkHwk

iTrader: (8)

No dremeling. Done by the supplier of the block.