6V92 Rebuild and hotrod thread

[Randy Dupree]

I have an 8.3 with a allison 3060,thats what i would do.


But,i do want to get in on this thread,but i have a big day ahead of me.maybe tonight.

[badandy]

Maybe some don't know, but I have retrofitted the LXI-style PWM-controlled hydraulic fan setup on my coach. I also installed a higher flowing fan blade and I set it up to spin the fan much faster. Putting out max HP in any gear on any grade in low 90 degree ambient I only need 50-55% fan speed to keep temp in check at 183. This is well tested, well vetted, and I have several thousand miles on it now. That doesn't mean 600hp is possible, but 425-450 seems reasonable once in a while.

[badandy]

Originally Posted by Randy Dupree

I have an 8.3 with a allison 3060,thats what i would do.
But,i do want to get in on this thread,but i have a big day ahead of me.maybe tonight.

I hate to disagree but the 8.3 isn't all that. It's a good reliable engine and it has more response down low, so more power under the curve, but that's it. An 8.3 swap into an FC, which weighs less and has way less power, would make more sense.

[badandy]

Here are the data plates. Took some scrubbing, but the tag says 325HP.

[Bearmtnmartin]

This guy replaced his 6v with an ISM and autoshift in his MC9. I talked to him while researching my swap. He is pretty happy. Might be an option for you pusher owners.

https://www.busconversionmagazine.co...?topic=17929.0

[markusfmeyer]

Last year while at a campground in Nashville, I was swapping my racor filter when a guy walked over and started talking to me. He was a retired fireman who loved the two-stroke engines. He started telling me stories about how they tuned the trucks to go as fast as possible from one stop light to the other. Apparently they were pushing major horsepower on the 6vs. His company and another often raced their trucks up this one hill in town to see who could get to the fire faster.

[diesel pat]

Originally Posted by badandy

It's time for some more HP! Nothing too nuts, but a little nuts is fine. 425hp seems reasonable. I solicit your advice and recommendations.

Does anyone have a DDC Field Service Data Book they can share, or scan, or let me scan in? If not I will pick one up on eBay. I think it holds many answers.

I currently have 9F90 injectors according to the plate. It's a silver 92, but it doesn't have a bypass blower. It's rated at 335hp supposedly. The turbo needs a rebuild, it's passing oil. I have a reman blower with a 100% bypass to install as well.

I would like to purchase injectors, but a bit confused about what to get. Different spray patterns, etc. Is it possible to have my existing injectors reman'd and changed around or is that not a "thing" with these kinds of injectors?

What cam differences are there? I see there were some different ones available. I'm not above swapping cams if I know what I'm getting for it.

I assume I have the "short" ports in my cylinder liners. Am I sacrificing much by not using the tall ones? They are 0.100" taller. I am not intending to do an in-frame and I doubt this change is worth it for the power.

I know there are OEM turbo choices that will work for this combo, but I'm thinking about what it would take to run a VGT turbo from something like an S60. Mounting it is the hard part, but nobody makes a turbo that mounts on the blower top plate like the original one. I can CNC a new top plate and possibly mount the turbo with the exhaust flange. The idea with the VGT turbo is to get some response down low, but also to run a better all-around turbo. Or I could run a BW S400 variant with no VGT. Same amount of work, simpler, inexpensive great turbos, and I can spec out whatever I want.

If I redo the top plate on the blower I might as well build an air-to-water heat exchanger into it. I could do a CAC, but running the water setup is more efficient and easier to route water lines around. This should be worth some ponies and just make it run cooler.

My cooling system is really good, better than any 6V coach has ever had, so I'm ahead of the game there.

Any transmission changes? I have the MT654CR and I think it's in good shape. Hard to really know, but it shifts nice and isn't cooked. I will be adding a cooler to this (currently none, but the fluid runs through the engine oil heat exchanger for some amount of cooling). I will go above its book rating, but that's also at 80,000 lbs IIRC. My gut feel is that the trans will be OK if I don't abuse it.

There are lots of ways to gain more HP. how much are you looking for
if you want more fuel you need a little more air(change blower drive gear,
turbo is that engine aftercooled ,clean aftercooler .
just installing Larger Injectors will cause greater cylinder temps =
shorter engine life, what IM trying to say is you just have to balance
it out a little, Fuel air turbo boost .you should be able to find lots of injectors
maybe a 9215 with a 9 hole tip to better atomize the fuel.
good luck and if I can help just let me know.

Pat 561-685-8537

[Randy Dupree]

Originally Posted by badandy

I hate to disagree but the 8.3 isn't all that. It's a good reliable engine and it has more response down low, so more power under the curve, but that's it. An 8.3 swap into an FC, which weighs less and has way less power, would make more sense.

I have a couple of questions for you.
How many BMC 37's have you driven?
Have you ever ridden in Woodys SP with an 8.3?


I was in Woodys SP when it was a low HP engine,like 250hp or so at 90MPH on the GPS.
He turned it up after that.


I think your mistaken about the 8.3.

[oldmansax]

Don Fairchild is the man to talk to. He had a company making a kit to produce more power and meet the emissions requirements V92 series engines. Different cam, blower, turbo, injectors, and some other modifications. The last I heard he was in Wyoming. He used to be real active on the Bus Conversions board.


TOM

[badandy]

Originally Posted by Randy Dupree

I have a couple of questions for you.
How many BMC 37's have you driven?
Have you ever ridden in Woodys SP with an 8.3?


I was in Woodys SP when it was a low HP engine,like 250hp or so at 90MPH on the GPS.
He turned it up after that.


I think your mistaken about the 8.3.

Doesn't a BMC 37 weigh like 32,000 lbs? What's an SP36 weigh? They are geared to both go faster and have an extra gear in the trans. So they are down about 6,000 lbs, have 1 more gear, and some more power under the curve to get it there a bit faster. In a PT I just think there are better choices if you're going to all the effort and expense, that's all.

Maybe next year at the WOG we can have a little drag race and we can place our wagers! Don't forget to dump your tanks