Turbo Chubby parts

[Greg Hermann]

At 8:17 PM 12/11/01, Bob Wooten wrote:
>Greg,
>
>Hope I did not step on your toes, implying that I was talking for you, that
>was not my intent.  Just trying to sort all this stuff out.

Huh?? Never thought you did.
>
>Onto topic, by negative work do you mean that when the piston comes up
>during compression it looses work (meaning that it is not free, it costs me
>something to compress the gas) & by injecting water & by it cooling the
>charge in the Cyl, it reduces the loss?

Precisely.
>
>But on the flip side that the water reduces the amount of power (positive
>work) that I would have got out of that charge if it were "dry"?

Yes.
>
>But the gain of the reduction of work is larger than the gain in the
>positive work, meaning that the NET is more HP?  If I am on track, this
>makes more sense (light bulbs coming on like a Christmas tree:)

BINGO!!
>
>Ahhhhhhhh, this makes sense.

Also makes sense as to why the bearing loads get lighter. With WI you are
not passing as much power around from one cylinder to another via the
crankshaft. Now that I state it that way--I would bet that there is some
reduction in torsional vibration in the crank, too !!
>
>So, IF I have a motor that is designed for WI I can design it around this
>net gain (& the others that you mentioned) & have a solid system that is
>going to be more efficient than one w/o it. (assuming a good state of tune
>initially)

That's my thought. Not backed up by experimentation and hardware that _I_
have done, YET.

Been busy for some time planning out a 605 cid (based on an IHC "LV" type
engine) that I think is going to end up with about 7 to 8 psi boost (over
sea level) and 10.5 to 1 or so mechanical compression. (Goal is 925 ft.
lbs., 1500--4000 rpm) Want to use full time WI to see if I can get it to
run on ULR fuel. It's going in a motor home, so water tankage is no
problem. The rev limit comes from Allison's converter. Planning to use VATN
type turbos. (Again, the lower EGT's should let the VATN's be reliable.)

Current problem is finding forged blanks for the pistons. (4-5/8" bore,
1-5/16" wrist pins, 2.4" pin CL to top). Have found blanks big enough in
6018 alloy, but _REALLY_ want to use 4032 !!! Why?? Seen, for instance,
some 4032 forged pistons for an FE Ford that spec only .0015" clearance !!!
IMO, this will give WAY better ring life for a street engine. And--I won't
have no steeeenkin' cast peeeestons, hyper or not, mon!!!

When IH christened these motors "LV" they did mean LARGE--5-3/8" bore
centers and 12-5/8" deck height ! Gonna use a block from a DV (diesel) 551,
all of them, gas and diesel, had 18 head bolts per bank, but the diesels
had 9/16" head bolts and oil cooling nozzles for the pistons. All five
mains are cross bolted. :-) Will upgrade to 5/8" main studs and 7/16" cross
bolts.
>
>OR, if I had a motor that was not designed around it I could increase
>something (air & fuel for example) & compensate for the increased load on
>the engine with WI & keep the efficiency of this system hopefully the same.
>(assuming a good state of tune)

Yep. The "designed around it" part is really just a higher mechanical
compression ratio and or boost level to take advantage of the fact that you
_CAN_ do that with the WI. When you really get into it, I would bet there
would be some cam timing things to be optimized. Likewise, I thoroughly
expect that there would be some turbine wheel and exhaust housing
adjustments to make on turbo(s) to get things just so, too. First thought
here is maybe one size smaller exhaust housing for a starting place.
Compressor(s) would remain the same. But--a bit more mass flow in the
exhaust (from the water) together with the significantly lower EGT's  is
telling me a slightly smaller nozzle would be in order. Of course--the
lower EGT's mean the turbines and the turbos would live a lot longer, too !

>
>OR if I had a system that was not of a good state of tune & I had to back
>out timing or air or add fuel to keep the motor from detonating or reduce
>the HP output, the WI could compensate for it & bring the motor back the
>other direction.  This though sounds dangerous, like trying to fix a severed
>arm with a Barney Band aid.

With the WI, I think you could just set the fuel mixture at 13 or even 13.5
to 1, even at full boost,  and use the water to stay away from the devil
detonation. The water is likely going to make it want some more timing
compared to no water, too. Seems to me that this sort of stuff would be
fairly easy and safe to sneak up on from a tune meant for no WI.

Greg
>
>No arguments from me, that's grumpy's job, ;-)
>BW


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