2 599 questions

[C.K. Piquup]

1)What year,model,application,or whatever are these motors found in? 2)Are these high-nickle?

[CleviteKid]

Jamie Avant or others can give you the exact answer, but my understanding is that the -599 was used in the 1991, 1992, 1993 time frame when both 6.2L and 6.5L engines were available, and were made from the same -599 casting. They are NOT the high nickel blocks used in 1982 or in the CUCV engines. But they ain't too shabby ! !

Dr. Lee :cool:

[Peter J. Bierman]

As a follow up question, what should be preferred, the 599 or the high nickle CUCV block?

Peter

[C.K. Piquup]

Sounds like the 599s were the latest MFIs.

[Peter J. Bierman]

I'm on to a 599 6.5 block for a resonable price.
I think I buy it and have both :D

Peter

[StephenA]

I have a '92 599 block which runs well at 225k mi, but would like to build a replacement engine before it ultimately gives out. From reading various block posts, it appears that finding a 6.2 CUCV block with no web cracks is the place to start, then I'd have both a 599 and a high nickle block to rotate every several hundred thousand miles.
My question is twofold:
1) is a 6.2 high nickel CUCV block bored out to 6.5 preferable to a 92-93 599 6.5 block?
2) are all CUCV 6.2 blocks high in nickel content, or only the ones made in '82-83?

My application will ultimately be a DB2-4911, 18:1 compression, high pop injectors, GM8 or pennisular turbo with Heath's boost controller, intercooled or misted and Heath's new BalanceFlo cooling mod.

[john8662]

1) is a 6.2 high nickel CUCV block bored out to 6.5 preferable to a 92-93 599 6.5 block?A simple answer, you can't bore a normal 6.2 CUCV block to 6.5 bore. The only block design that can is the 599, but why bore, you can make the same power out of a 6.2 as you can a 6.5 when using 6.5 components (heads included). I was told that if you leave a 599 at 6.2 bore that you have .080 thicker cylinder walls, makes me feel better!



2) are all CUCV 6.2 blocks high in nickel content, or only the ones made in '82-83?
I know for sure that the 82 blocks were cast in a higher nickel content, some of those blocks made it to the CUCV's. I've got an engine that came originally in an M1008 that has a date stamp of 82 on the back of the block, yet it was an 84 model. It was the original engine, doesn't look completly like the other 82 block I've got, but maybe they were cast using the same formula. I think thats where we get the idea that the CUCV blocks are better. I'll ask the Avants about this later this week.

[C.K. Piquup]

From what I understand,the military-spec engines in the CUCVs were required to retain the higher-nickle content as found in the first year`82s.The 599 casting is from the transitional time when GM made it`s last 6.2s and first 6.5s.For that reason the 6.2 bored blocks can be over-bored to fit 6.5 pistons.No higher-nickle,though.The only reason I would want to bore a 6.2 block to fit 6.5s would be to go to 18:1 pistons on a hi-fuel rate/hi-boost motor.You can buy 19:1s from Peninsular diesel for the 6.2.

[StephenA]

Originally posted by john8662:
</font><blockquote>quote:</font><hr />
1) is a 6.2 high nickel CUCV block bored out to 6.5 preferable to a 92-93 599 6.5 block?A simple answer, you can't bore a normal 6.2 CUCV block to 6.5 bore. The only block design that can is the 599, but why bore, you can make the same power out of a 6.2 as you can a 6.5 when using 6.5 components (heads included). I was told that if you leave a 599 at 6.2 bore that you have .080 thicker cylinder walls, makes me feel better!



2) are all CUCV 6.2 blocks high in nickel content, or only the ones made in '82-83?
I know for sure that the 82 blocks were cast in a higher nickel content, some of those blocks made it to the CUCV's. I've got an engine that came originally in an M1008 that has a date stamp of 82 on the back of the block, yet it was an 84 model. It was the original engine, doesn't look completly like the other 82 block I've got, but maybe they were cast using the same formula. I think thats where we get the idea that the CUCV blocks are better. I'll ask the Avants about this later this week. </font>[/QUOTE]Wow, if that's true about the same power, that might be one heck of a stable engine: a seasoned high nickel alloy block with no web cracks (if it was going to crack, logic has it that it already would have), thicker cylinder walls, faily easy to find, etc., etc. How many 6.2's are out there with 300 HP using the same mods as the 6.5 project engine? Do you know if the power mods make for any new block cracks? Never thought I'd be into a 6.2, but sounds quite interesting if the power can be had more reliably.

I'd be very interested in what Avant has to say about that block. Makes sense as C.K. says that the military spec would hold after 82. Do you know if Avant routinely rebuilds these high nickel blocks with 6.5 heads, 4911's & GM8's, etc?
Thanks!

[ 04-07-2005, 07:49 AM: Message edited by: StephenA ]

[StephenA]

Originally posted by C.K. Piquup:
From what I understand,the military-spec engines in the CUCVs were required to retain the higher-nickle content as found in the first year`82s.The 599 casting is from the transitional time when GM made it`s last 6.2s and first 6.5s.For that reason the 6.2 bored blocks can be over-bored to fit 6.5 pistons.No higher-nickle,though.The only reason I would want to bore a 6.2 block to fit 6.5s would be to go to 18:1 pistons on a hi-fuel rate/hi-boost motor.You can buy 19:1s from Peninsular diesel for the 6.2. 19:1's sound great- does Peninsular put their high output turbo on high nickel 6.2's?

[john8662]

According to Benny at the Diesel Depot, you can make the same power out of the 6.2 as you can a 6.5. Most of this is due to using the 6.5 heads and fuel system. The 6.5 heads supposedly flow better, I don't have any solid numbers on this.

If it were me I'd take a 599 6.2 (the one with the thickest cylinder walls), keep it 6.2 bore, install lower compression pistons. Then, because this isn't a solid high nickel block, I'd Splay the Mains, keeps the worry about cracking mains webs down to a minimum.

On the CUCV block with the higher nickel content, to drop the compression ratio, you can do several things, adjust the wrist pin height, shave the piston, or install Penn's 19:1 pistons (that are modified in the same fashon as previously mentioned). But the Penn pistons are ONLY available in stock 6.2 bore size, so no .020 or .030 oversize pistons available.

[arveetek]

Originally posted by john8662:
According to Benny at the Diesel Depot, you can make the same power out of the 6.2 as you can a 6.5........... But the Penn pistons are ONLY available in stock 6.2 bore size, so no .020 or .030 oversize pistons available. I'm currenty rebuilding my 6.2L. I'm using my original '82 red block that has been bored .030" over. I was going to mention that Peninsular pistons are only available in std. bore size, but John beat me to it! I called them and asked about oversize pistons, and they don't make them. My solution was found at the Diesel Depot, where they made me custom lower-compression, ceramic-coated pistons at a great price.

My 6.2L will also be sporting 6.5L turbo injectors and 6.5L 4911 injection pump. With a turbo putting out 14 psi (before the rebuild), I ought to have a strong runner. Should outpull and outrun any stock 6.5L pickup.

You can read about my progress in this thread. (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=2;t=003466)

Casey

[StephenA]

GREAT thread- Thanks!

[john8662]

Just an update on the status of whether CUCV blocks are higher nickle content above what the civilian ones are. The responce I received was that there hasn't been anything that can be documented to prove this this is the case. To be sure, only the 82 blocks had the higher nickle content, and that can be seen just looking at the block.

So in conclusion, it doesn't mean that the Military didn't spec the 6.2's to be a hardned block, but there is no proof that they did and that it was carried out. The main conclusion is that GM did different things throughout the production run to strengthen the blocks, different mixtures of alloys, etc.

[StephenA]

Interesting, John- where does your data on this come from?

[john8662]

Stephen,

I call The Diesel Depot out of Georgia, they specilize in these engines, I figure if anyone knows it's them. Jamie and Benny are the two sources of information that I'm aware of.