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simon
03-27-2007, 22:27
Well I am about ready to rebuilt the fried engine in my 98" see signature", but am a little confused as to what would be the best options to use as I plan on pulling a heavy loaded stock trailer from time to time.

I was thinking of getting upwards of 275 hp out of it. is it doeable without spending a fortune ? as money is as rare as square eggs around here.

I am able to buy a new AM general bare block for $1450.- cd ,and new heads for 215 a piece, the crank and rods are good and salvaged from the old engine as well as the rest of the kling ons that are needed.

Do i go with the 18-1 pistons ? Will the new block be strong enough without
a ful girdle or splayed mains.?

I probably will have to use a intercooler and bigger exhaust as well.

I have the dual thermos and the high flow waterpump.

As the airconditioner is going to be eliminated I was wondering if I could Use the cooler as transmission cooler instead of that little thing that tries to do the job now. I will be putting a bigger oil cooler in to.

What about the IP and the turbo, can I go with stock ? A chip maybe?

I most likely have missed a few things. I am well capable to put the thing together as I have done plenty others brands and sizes , but I have never souped one up as I intend on doeing now.

To all you guy's that " have been there done that" suggestions please.!!

There is so much info on this site that I can't see the forrest trough the trees no more

redbird2
03-27-2007, 23:33
I use my signiture truck to pull a 20' gooseneck livestock trailer and a flatbed with tractor on it sometimes. Here is how I build my engine however the more HP you want the more money you can send.

I started with a 94 block, had it hot tanked you starting with new is a great advantage. we bored my 20 over to take care one cylinder had block magnifluxed.

went with new heads if I where going to do it again I would have port matched the manifolds intake and exhasut to the heads just to help increase air flow into and out of cylinders.

the piston i went with Manhle pistons stock compression ratio as I did not want to have an cold start problem in the winter as I have heard happening with the 18 to 1

I had the rods upper end bushings replaced as they had 245,000 miles on them think it ran me 85.00 us to have that done cheap insurance

had the crank micro polished still able to run std bearings even with those miles

I then had the rotating assemble balanced to help run smoother.

injectors 40 hp plus ones
stock ds4 fuel pump
4" exhaust
heath maxi torque PCM
turbo master
gear to gear timing set up timing no longer issue due to wear
full gauges a must if pulling weight
after cooler added toward end of last summer build my own set up
sst oil cooler lines and big oil cooler
Kenndy fan clutch to keep it cool going over Rockies
just added differerant air cleaner set up for better flow
and mandrel bent cross over my factory one didn't flow well cause high exhaust temps better after install

good luck you will get differing ideas for everyone keep open mind and read everthing and make your mind up RJ has a nice write up on building a good engine read that as well

moondoggie
03-28-2007, 10:19
Good Day!

"I am able to buy a new AM general bare block for $1450..." Boy, are you the lucky one. There's LOTS of folks who'd like to just be able to buy one of these - apparently only folks selling complete engines (Peninsular etc.) can get them.

From what I've read here over the years, if it's truly the latest-greatest block, it should be strong enough; Peninsular (& probably others) thinks so, that's what they're using. But if I ever build a 6.5, it would be hard for me to skip getting the splayed mains, like RJ does. It's mondo expensive, but I'd hate to build one without it. The block cracking poll seems to indicate that 6.5's crack blocks due to being worked hard, whether or not they're modified for more power. I know one thing: if RJ can't break his engine, it can't be broke - he works the snot out of his & takes no prisoners. :eek:

Personally, I'm no engineer, but the stud girdle concept doesn't impress me at all. Unless the girdle had no holes in it, & it was drilled & pinned to the bottom of the block, things can still move around, & that's what allows the cracks. The problem is, it looks like an average 6.5 can pull heavy for 50K - 150K miles B4 the cracks show up or she grenades, so a guy might never know if a stud girdle helped or not - if you only pull intermittently, the 6.5 would likely have gone 200K miles or more without it. If only there was a way to be sure... :confused:

Keep us posted. It's fun to read what other folks are up to.

Blessings!

More Power
03-28-2007, 11:44
Most of the block cracks occur in the late 1996 to 2000 GM piston oil spray blocks. Those 1992-1995 no-spray blocks don't have this problem. I have heard of a couple, but not as a rule.

The 1993 model-year 599 casting used in the 6.5 Project truck was still putting power to the ground at 200k+.

Jim

ronniejoe
03-28-2007, 18:06
I have a 92 599 block downstairs with two mains cracked...

Kennedy
03-28-2007, 20:05
I'd be a bit leery of the supposed "new" block and heads. If I could buy them I would. There is only one rebuilder contracted to do remans and they receive the blocks with new camshaft and bearings installed.

I don't think $215ea will buy the cheap China head castings either.

Maybe someone has located cull/scrap engine blocks and heads???


I thought that the a good seasoned 599 block was the best also. I evn had it heat cycled and shot blasted. Less than 6k later it had 3 broken webs. I then built an oil spray 506 block with the big spray nozzle holes using my splayed caps and that one runs today at high power w/o issue...

simon
03-28-2007, 22:24
OH Boy, now what.

As for the cheap block and heads, It is actually a well known supplier selling them, but I will contact him again and get his assurance as to authenticity.
I will post again when I know for sure.

I have personally seen one of these block's at my local engine shop, and the shop owner said they are the real thing. The same folks offer short block's at 3400 bucks.

The original engine got overheated badly and has a 1" crack at the 4th web, and both heads are cracked at front and back plus 1 melted piston .

I do have a running 95 out of a chevy that i totalled last year, but figured to start with a better block in order get the most power out of it without the dreaded cracking problems. I might have to use that one after all.

AS for girdles I to question them, I personally feel the only ones that will work are the ones that incorporate the maincaps and panrail in one piece, but that is a expensive piece of machining. Splayed mains look good but the machining is probbably more than I can afford too.

What about the marine pump is that electronic, if not how does a guy bypass the ecm ??

Ronniejoe has a couple of clickable links on his post , but i do not know how to get in , it refuses my password.

Anyway keep coming with info please, I apriciate every one.

Thanks people.

More Power
03-29-2007, 11:57
Less than 6k later it had 3 broken webs.

Was this the one with the loose damper?

Kennedy
04-01-2007, 20:38
My memory is a bit vague, but IIRC, the original engine that blew to pieces is the one that the balancer was "less than tight" on, but with a 3 pc crankshaft it's hard to say whet really hapened there. The gear drive etc was beat to death in short order. The reman was done by the book and at 18:1 the first time, them splayed caps the second time...

Mark Rinker
04-01-2007, 21:58
...both my K3500s were 1994 and broke crankshafts, at under 150K miles. The first had cracks in the webs. I never saw the second apart...

The 1998 (oil spray) replacement engine has 110K total miles on it, 50K chipped and turbo turned up.

I guess only time will tell!