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hello, and need advice with too many options

S

ssgttype

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Hi, I have been lurking for a while, and reading up on the 6.2/6.5 platform, and am ready to finally swap one into my 84 k5 blazer. The problem is that I have too many engines to choose from...my uncle is a bit of a hoarder, and likes to buy military surplus stuff, so in his yard alone I have free rein at running m1008/m1009 engines, an 87 hummer 6.2, an 06 center mount 6.5 that were not sure if it runs, and a 98 civilian k3500 6.5turbo that has 12k on it...was supposedly hit by lighting and parked, doesn't run, but theyre are no burn marks anywhere on the truck, so mechanically it could be fine.

Anyway, I want to put together one engine, most likely with a turbo for my blazer, obviously the 6.2 in a m1009 is the easiest because literally everything is there, but I was looking for the forums help to put together the best combo, ie 6.5turbo heads on 6.2 block, I don't plan on towing anything huge, I only have a 4x8 trailer, and its not my daily so I'm not looking for necessarily the best MPG money can buy, just a cheap/free project to make my blazer a diesel. I also have a t3 flange turbo off of a cat 3116 engine that will probably do just fine, since I know the gmx turbos are not that great.
 
I would pull whatever engine, and check it out, most likely put 6.5 head gaskets, and ARP studs in it and go from there. I am a mechanic by trade, so I'm not worried about the work side of things, only which parts to grab.

I already know that the serp setup off the 98 will be going on, and at least the passenger side exhaust manifold, but not sure which injectors I should try, will be using the cucv pump most likely, as I don't want any unneeded electronics or wiring.

My blazer has an SM465 4 speed, np208 transfercase, dana 60f and 14bff rear with 4.56 and a Detroit, and hummer take off 37s.
 
No matter which you run, pull it apart for new gapless rings, new bearings especially cam (remember crank is select fit).
Do new oil pump. Seriously consider getting things like bearings coated, maybe pistons, cam, etc too. Adds life and drops friction.

IMPORTANT- if serp belt, make sure to use spin on fanclutch style waterpump not 4 bolt. Use block of thermostat crossover if single or if dual then get Leroys brf.
Kennedy still has the best fanclutch unless you want to copy AKdieseldriver’s electric fanclutch from the ford.

NEW oil cooler hoses.

Start with new harmonic balancer and drive pulley- AC Delco good for 100,000 miles cheap ones way less. Leroy makes billet drive pulley that is life time and fluidampr is good for 500,000 miles.

Tons more on the to do list once it is together.

Get new injectors from leroy.

What turbo you gonna run?
How will you use the rig- tow alot?
 
The 6.5 turbo manifold airflow nightmare fortunately won't clear the HVAC box for the crossover on the OBS 80's stuff. You will want a Banks manifold or do something custom.

@Burning oil You will want one of Leroy Diesel's timing gear kits to get rid of the stretched to hell in 30K miles from driving the IP chain. @Will L. is taking the fire out of my jets on Gapless rings, however, my results with cleaner oil and oil samples are a link in my signature.

The engine you use will be the one that's crack free. 6.2/6.5 more or less same thing unless you go big turbo. Then you want the 6.5 heads with 6.5 turbo precups. Hint: resale for "just an engine" is higher for a 6.5 so if they are all good use the 6.2 and sell the 6.5's. If one is an Optimizer use it as it is less prone to cracks like the GM cast stuff.

End of the day consider 210 ECT "redline" for the engine as rings turn to jello over that let alone crack risk.
 
just checked the block codes on the back of the 6.5t hummer engine, its a 12555506, dash says it only has 28xx miles on it...so I think ill start with that engine.

what is wrong with the 4 bolt style fan clutch? curious, as its what I have, trying to not spend a fortune, as its not my daily and I don't really need an all out tow rig.

the other thing is, I read that the center mount turbo heads are different from the rest of the 6.2/6.5 fleet, and as I'm pretty sure the center mount setup wont fit in my truck without major firewall surgery, id like to use the civi 6.5 side mount turbo setup, with either the gmx turbo or the cat turbo that I have...again trying to stay on the cheap. so will the civi 6.5t heads bolt up to the optimizer which I think is the 506 block that I have?

I'm thinking the best combo of what I have would be hummer 6.5t block, civi 6.5t heads/intake/turbo manifolds/injectors and then a mechanical 6.2 db2 pump?

no matter what I will put eyes on the timing chain and bearings, as well as look for cracks, but I think gapless rings, new bearings, ceramic coating things etc will break the cheap/free budget. I understand that would make for a better engine, but for my needs I think a close to stock setup should be fine. only for sure "upgrades" to the engine would be new gaskets, 6.5 head gaskets, probably felpro .010 ones, and ARPs.

also will the civi 6.5 waterpump and accessories fit the hummer optimizer? I'm assuming they will.
 
The only real differences in the heads are the center mount turbo heads have 60* intake bolts where as the truck ones are 90*. Also the precups can be different. If your gonna run a turbo ideally you want the diamond stamp precups.
On the WP the 4 bolt style can be either 90 or 130 GPM the 130 will have HO cast on it. The best version is the spin on style as it more closely balances the flow between the heads. 6.5s are kind of a heat challenged motor, it's really easy to overheat them. You really want to keep them at 210* or less to avoid cracks, losing temper in the rings etc.
That's why I went with the electro viscous fan clutch. Here in AK it's possible to overheat the engine before the fan clutch engages. So mines setup to activate via engine temp.
 
I would re-ring a 6.x engine before I would put ARP head studs in on a budget. I made your mistake twice of ARP's and not doing rings and both engines had a lot of blowby. It's slightly easier to replace the head bolts than replace overheated rings: as another member put it from an engine 'you could air up the tires with blowby'. New rings at least and consider the optional ~$90.00 gapless add on. Just glaze break the cylinder walls and new rings. GM castings are not worth machine work cost. And gapless rings + Glaze breaking gets me zero blowby and has for the past 30K miles.

A picture of the valley of the 2006 block should be posted here as we are looking for the International logo cast in it etc.
 
Whereabouts in the valley am I looking? It still has the center mount turbo setup mounted and it's in a Hummer so I can't see much of the valley easily.
 
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