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gonna build a race truck

well i know that kennedy diesel makes splayed mains for. and yes i would have to build up the lower end but when you start going for proformance you normaly have to start building up the whole thing or it will have a view port in the side

Why don't you start with the GEP P 400 with forged crank and main bearing girdle. That should be bullet proof for any boost level you want to throw at it. Then throw twin ATTs with spooler valves and crank the tune to the max. Don't forget the GoPro video camera.
 
ARP studs should keep the heads on.
Twin turbo's will allow for a more efficient exhaust manifold/header design and dual exhaust to let the sucker really breath and exhale which is win win from rooter to tooter.
P-400 heads were tested in Afghanistan where service members were routinely destroying them. After the new heads proved near bullet proof to drivers who were known to be motor killers (long story), the team went after the rest of the motor which is the current design marketed. You'd be fine with it if that is your choice.
Are you going to run 1/4 only or longer distances?
This will be a great project to follow, thanks.
 
ARP studs should keep the heads on.
Twin turbo's will allow for a more efficient exhaust manifold/header design and dual exhaust to let the sucker really breath and exhale which is win win from rooter to tooter.
P-400 heads were tested in Afghanistan where service members were routinely destroying them. After the new heads proved near bullet proof to drivers who were known to be motor killers (long story), the team went after the rest of the motor which is the current design marketed. You'd be fine with it if that is your choice.
Are you going to run 1/4 only or longer distances?
This will be a great project to follow, thanks.

how about that long story?
 
The thing a lot of you keep seeming to forget is that the 6.2/6.5 was designed from the ground up as a LIGHT duty diesel engine. The 5.9/6.7 Cummins, Ford 6.0/6.4/6.7 Powerstroke and 6.6 Duramax were all designed as MEDIUM duty diesel engines. A STOCK 5.9 Cummins bottom end and block can routinely handle 700-1,000 HP with no problems, yet a stock 6.2/6.5 bottom end and block has problems much past the 300-350 range without something breaking.

If you are serious about trying to compete with the Dodges, Fords and Duramaxes with a 6.5, at least start with a P400 short block and a forged steel crank as your foundation, run about 16-16.5:1 compression and go from there. Consider, also, the inherent limitations of the precup IDI engine design vs. the combustion chamber integral piston DI design. Flame front travel out of the precup will be greatly affected at the high boost levels needed to reach 600 HP and that needs to be accounted for, too. Again, the fueling limitations of the injectors/IP will be your biggest hurdle, perhaps looking at an 8 cylinder version of the Bosch P 7000 style IP would over come the short comings of the Stanadyne DB/DS, but then you're looking at some serious $$$$ again for the custom machining, engineering and fabrication - even if you DIY - to pull this off.

Not being a Negative Nellie, but I am giving a serious Reality Check to the daydream. Anything is possible if you throw enough money at it, and this would become a serious money pit quickly, especially without lots of free machine shop (your own) access and corporate sponsorship for high dollar parts and one-offs.
 
Not to mention dealing with three times the heat generated vs. a stock 6.5. If you think the cooling system is borderline on a 190 HP stock motor, how about at 600 HP?
 
If you just want to build one to build it, but all means go for it. But if you want to be competitive, then it's a losing battle. I can't remember his name, but somebody over at comp D did build a 6.5 years back with a P7100 inline pump and all the other goodies available at the time. And was never impressed with it. He replaced it with a stock 5.9L out of a 96 and turned the pump up and added a turbo and blew the 6.5's times away like no tomorrow. This was with the same truck, same trans, and same driver. The IDI is just not going to be competitive unless all you want to do is bracket race in a lightweight truck. So be realistic with what you want to do before you go shelling out a lot of money to learn what others before you already have.
 
Find a lighter truck for starters. A K2500 isn't very light at all, even a single-cab.

I'm not so sure on the DS4's ability to do anything more than 80mm3 of fuel, especially in a 1994 with OBD-I. Not so sure on the OBD-II stuff, as I don't have the programming to modify and access that yet. But I suspect it's similar in it's limitations. I base this suspicion on the fact that you don't see Kennedy, Heath, or SS Ripoff Supply, or KoHo offering anything that's higher performance than the OBD-I stuff. Dunno...

Do a mechanical injection pump. I'm doing 125cc right now on a plain ol 833 pump.

I'd recommend a true 1/2 ton, doesn't have to originally be a Diesel. I'm building up a 1992 C1500 Extended Cab Short bed from the frame up right now, cause it's light and it did have the option of a 6.2L diesel back in the day. Not for drag racing though...

My 1982 C10 does pretty good power wise but you cant put it to the ground in a single cab short bed unless you spend tons of money back halfing the truck, and then it's still a crappy hooking truck anyways (trucks suck on the dragstrip concerning traction, unless they're 4x4).
 
I really wouldnt let these guys discourage you. Like I mentioned before, ideas like this spark innovation. And everybody said that a Quick Spool Valve wouldn't work on a V8. Proved them wrong. As mentioned, you have my support.
 
I don't know, i've seen what a modified 6.5 can do and it's not that hard to make them run with a mildly modified v-8. Fueling is the hardest thing about this. When going over 300 hp on the db pumps it is hard to get them right.
 
If you build to much power with a 6.5 the rods will bend,and the pistons catch the crankshaft counter weights. So far I have bent 4 sets of rods,and blew up 6 motors. My head gaskets are blown right now on the 6.2 ,even with studs and orings. If your determined to build this I would recommend lowering the compression a lot,like 16-1 or less, and use a 6.2 bottom end,they can take more cyl psi,and won't blow up the instant it bends a rod.
 
My thoughts:

different truck. like said above, K2500HD isnt light. keep the beloved 5speed truck stock-ish for reliable towing. I vote find a C1500 shortbed/ reg cab with a v-8 and automatic, and stuff a 6.5L 4L80E in it.

and this one will blow some minds: wouldnt an auto be better? yes, I asked if an auto would be a better choice! :) I would think for drag racing the auto would do better, especially for loading up a big turbo setup to get it to spool.
 
how about that long story?

Hopefully not too off topic and not as long as most of my posts.
From the engineers at GEP a couple years back at the Salt Flats.
The heavy loads the HMMWVs in their various configurations, especially the uparmored ones, were cracking heads right and left and the the company was shipping heads to Afghanistan at a prodigious rate each month. “Containers” is the phrase I recall but the number was over a thousand per month. At the time we were still in Iraq but that was drawing down. Anyway, the engineers worked on strengthening the heads through alloys and such, put them through stateside testing and then in collaboration with selected motor pool leadership overseas, the sent more over for field testing. Each motor pool NCOIC knows who is going to blow a motor or, who has the reputation for doing so on a routine basis (stuff happens but then there’s the guys who seem to delight in the carnage). During the test period, these consistent performers were sent out with the new designed heads and none of the test units came back NMC for the heads.

A winner.

The engineers then went after the rest of the motor to try to make them more reliable as a unit, as the reputation shows, succeeded in delivering some have deemed ‘the motor GM should have fielded in the first place.’
 
Go ahead with your project

For BigBearZach: go ahead with your project :thumbsup:
Believe me or not, but my good old 6.5 is capable to stand head to head climbing a hill with a STOCK 2013 Dodge Ram 2500 6.7l Cummins (370 hp, 800 lb-ft) :cool: and easily outruns all stock ISB Cummins and Ford Super Duty PSD's empty or loaded. :D
My truck is a 1994 chevy k2500, and my mods are: DB2 mechanical injection pump turning all the way up, 100 ghp 18 psi lift pump, vented fuel cap, open intake, HX35 turbocharger running at 22 psi (stock compression), 3.5" straight pipe, 3.42 gears, NV4500 transmission.
I know that a 6.5 isn't a race engine, but with a little "affection" you will have some fun :D
 
Dynodynamics chassis dynometer.

271.9 @ 3200 rpm, 446.3 lbft @ 1900 rpm.

Crank is estimated around 300 hp.

Just getting into stock lb7 territory at that level.

You don't want to know how much money I have in it and how much is done to it.

Lets just say I could have had a very nice and lightly used DMax by now.

I was partly forced into it, partly wanted to do it.

If I had it to do again, I would not.
 
Nice torque down low. I am jealous. I was only 1100rpm above your peak torque hahaha thats ok, my engine spends most of it's life around 2500rpm+ anyways.
 
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