Modified 6.2 turbo diesel

[6.2 turbo]

The gaskets are victor rienze ,the pistons are custom ground. I might try an external waste gate, my last test drive it was well past 60 psi boost. I would guess horsepower to be around 300, its hard to say, all the missing and surging at top end is gone,the pump still needs some work on the part throttle and idle,I might get the parts I need to make the advance work,that would help driveability a lot and would start better because it would retard the timing when starting. Here is some pictures of the turbo hose, the second one seems to hold.

 

[buddy]

You might try some constant torque clamps, or just more of what you have on the intake plenum, instead of them hose clamps. The hose clamps wont hold more than 20psi.

Can you get a video of the boost gauge reading 60 psi in that thing? It sounds so unreal that the DB2 fuel output could support that much boost.

How much did you cut off the top of the piston?

 

[6.2 turbo]

About .090 thousands to 1/4 inch from the outer edge. I might get a video of the boost gauge, before I take the motor back apart. Ive been trying for probably 2 years to get more fuel out of this pump, its been on and off the motor more times than I can count,Ive tried lots of ideas,and seized alot of pumps,and sheared cam pins,and pump drive shafts,and it still isnt near perfect but I got pretty much fuel, I think I could get more out of it, with a lift pump that makes 100 or more psi and delete the charge pump, Ive got to check charge pressure at full throttle and full load and see how far it drops, I noticed my lift pump pressure dropped from 12 psi to 6 psi at full throttle,it is a holley with 1/2 inch line to the filter, and 3/8 after,also still 3/8 pickup in the tank.

 

[schiker]

6.2 have you seen the video's of the Massey tractor with our little GM 6.? V8 and 2 DB pumps mounted on it in parallel? Thus for short times its been proven to be able to take appreciably more fuel. Another screamer Heath's 500hp legend as mentioned above somewhere.

As many people say on here it aint going to hold together for long working hard at those power levels (unless you modify the cooling significantly) but for a drag truck or sled truck it might take longer to distruct than most think.

I suspect Peninsular found that at heavy load and rated power for a sustained time the oil temperature slowly rose until it started to break down and a piston(s) gualled. They lowered compression to take away some of the thermal load on the piston. I have done a little bit of engine heat balance testing and it generally takes from cold 20 ish minutes for the ECT to stabilize at a load BUT can take up to an hour of steady state for the oil temp to stabilize. Its kind of hard to load a truck up to max for this long.
Reference....Kubota, Yanmar, and Deutz specify about 248F as max continuous oil temps (conventional dino oil) at the pan for 10,000 hrs engine life warranty and reasonable maintenance cycles etc. But oil will tolerate short times above this (breaks oil down faster). Oil temp is important but you really can't use it real world as a safety gauge like ECT it reacts too slow.

I'd suggest using Synthetic motor oil for this beast. Rock on. Look forward to reading more about it.

PS. Have you talked to Wester's they sell a special bastard IP that is suppose to increase the output of a DS pump a little (use a different model pumps cam ring with updated rotor, plungers, rollers ??? etc.). Something like the '94-95 ish era HD DS pump's camring had the tallest cam lobe???? I suspect they are probably getting it through Peninsular???? Its not going to get enough fuel for you but they may be another source for ideas/info.

 

[6.2 turbo]

I've seen the massey video,not sure if it had two pumps at that time. Never heard of Wester's. I'm running regular 20/50 oil now ,no oil cooler, or adapter,internal filter bypass blocked, and chevy 8.1 oil filter to clear the front drive shaft.

 

[reddog]

6.2 turbo,
I think I read earlier in this thread that you haven't done much to the bottom end except a girdle. Is this correct? Did you do the girdle? Did you align hone it with the girdle?

 

[6.2 turbo]

Just the girdle no align hone, as long as the girdle don't bind on the holes it should be ok, if your line honing any way it probably would be a good idea to have the girdle in place. My girdle is just 1/8 inch angle iron,and stock bolts.

 

[reddog]

thanks for that. I know the 6.2/6.5's have crack issues but it sounds like you run the piss out of yours and it's holding together.

 

[Woody35]

his engine though is not a typical 6.2/6.5

 

[6.2 turbo]

This is not a daily driver, though the bottem end seems to take alot, probably a mater of time,when I finnaly get it right is when the bottom end will come unglued, also I think my low compression saves it alittle,but I think its limiting my power somewhat , can't imagine what would happen with stock compression and 60 psi boost, and the same amount of fuel I have now, for sure it would have more low end power, I'm seriously thinking of ditching my pistons for stockers, and running around 18 - 20 to 1 compression, I think the motor would be easier to tune. It's hard to build a 6.2 that's this unusual, and I'm kinda on my own, its much easier to build a motor with a tried and proven combination. Ill be pulling the heads for the fourth time, as soon as I have time to do it.

 

[Anubis]

Just the girdle no align hone, as long as the girdle don't bind on the holes it should be ok

can you explain this in more detail. I do not understand binding in the holes ..... I can guess at what align honing is ..... no, i guess i can't....

 

[6.2 turbo]

If you make your own girdle and the bolts bind in the holes when you tighten them it will pull the bearing cap side ways, align hone is done at the machine shop if the main bearing bores are not right.

 

[Anubis]

so then if I bought the DSG kit from Kennedy ...... would that need to be align honed?

 

[6.2 turbo]

Should be fine.

 

[chevyinlinesix]

so then if I bought the DSG kit from Kennedy ...... would that need to be align honed?

It will distort the main caps. The 6.5 has relatively flimsy main webs, and it will in fact distort when you install studs and a girdle of any kind. It is common engine building knowledge that changing anything to do with the main caps causes distortion, and will require to be align honed, and possibly bored.

 

[6.2 turbo]

If you are getting a motor machined it should be checked with the girdle in place , but on a used motor with no machining and loose clearances it shouldn't mater, mine is fine.

 

[uniquediesel]

The DSG kit is intended to be installed in running engines and during rebuilds.

It will likely change the alignment, how much and how critical, dunno, worth a check. Not enuf to get worried over. I've done this girdle in several engines w/o any ill effects.

 

[SmithvilleD]

Have either of you guys run into odd main bearing wear patterns or block main registers that are significantly out of square or straight/height across the registers?

Any association/correlation btwn blocks w/ main web cracks and the main register tolerances being sloppy or shifted?

 

[Rafedial1]

one of the best threads I've read in awhile.

6.2 turbo, you still thinking of building db2 pumps with the 4 head and rotor?
I'd be in for one.

I don't mind the "quirks" of a higher output pump. so let me know when and how.

 

[Rafedial1]

Any association/correlation btwn blocks w/ main web cracks and the main register tolerances being sloppy or shifted?

would like to know this as well.