re: more power

[themissingparts]

Hey everyone,

I had a diesel mechanic look at the engine on my 36 passenger Ford Wayne school bus. He said there is definitely a governor and that to get it off the Bosch in-line fuel injector needs to be taken out and recalibrated and that it would cost between one and two thousand bucks. Is there any way to get more power fairly cheaply, without removing the governor?
Any thoughts on this would be much appreciated.... (Oh yeah, the engine is a 7.8 Brazillian)

[Steve]

Take a look at this thread, lapeer posted some new choices for the injector.

viewtopic.php?f=6&t=588

[themissingparts]

Thanks Steve....

[frank-id]

Get away from that mechanic. He is not your friend. All diesel engines have a govenor. All diesel engine govenors can be adjusted. Besides adjusting the govenor, there are other methods of gaining power. Adding a turbo adds about a 10% increase in power, an inter or after cooler makes power increase, reprogramming trans gives more get up and go and a higher rear axle ratio makes better speed with less horse power. I'm changing my rear gears for a better top speed at a lower cruising speed. Frank

[crazycal]

Get away from that mechanic. He is not your friend.

+1000

[Hex]

Originally Posted by frank-id

I'm changing my rear gears for a better top speed at a lower cruising speed.

How hard/expensive are you finding that? I've got a great hill-climber, but I'd like more over-the road speed, so I've been thinking about swapping out the rear gears.

[frank-id]

There are several methods of changing gear ratios. The easy way is to find a truck over/under drive gear box. These are hard to find but a great device for having all the good desirable gears. Find a overdrive unit to bolt to rear of current transmission. Finally, your vehicle is a very new type bus, so the parts needed could be available from a truck salvage place. I do not have any cost information. New gears to change ratio are easily available. Now the big decision will be..... rear gears ratio wanted/needed. Not all roads are steep nor flat. My goal is for more top speed and economy. My choice was 3:55 and currently my bus is 4:10 ratio. Changing the gears does require some mechanical skill. The most important part of the task is setting up gears for preload and gear pattern
in relationship to gears contact. Maybe a truck mechanic can be recruited for the fine adjustments. The gears are heavy and require a floor jack or trans jack to lift. A salvage gear set assembly will merely need some inspection by a mechanic, and probably no adjustments. Be sure to check the gears and lube carefully. If the donor is a wrecked truck, yea!!!!! The results are very rewarding. Maybe some one will need the old assembly. Frank

[M1031]

Originally Posted by frank-id

There are several methods of changing gear ratios. The easy way is to find a truck over/under drive gear box. These are hard to find but a great device for having all the good desirable gears. Find a overdrive unit to bolt to rear of current transmission. Finally, your vehicle is a very new type bus, so the parts needed could be available from a truck salvage place. I do not have any cost information. New gears to change ratio are easily available. Now the big decision will be..... rear gears ratio wanted/needed. Not all roads are steep nor flat. My goal is for more top speed and economy. My choice was 3:55 and currently my bus is 4:10 ratio. Changing the gears does require some mechanical skill. The most important part of the task is setting up gears for preload and gear pattern
in relationship to gears contact. Maybe a truck mechanic can be recruited for the fine adjustments. The gears are heavy and require a floor jack or trans jack to lift. A salvage gear set assembly will merely need some inspection by a mechanic, and probably no adjustments. Be sure to check the gears and lube carefully. If the donor is a wrecked truck, yea!!!!! The results are very rewarding. Maybe some one will need the old assembly. Frank

For my Ford, I'm changing the gears from 4.88s to 3.7somethings by buying them from Arvin Meritor. Here's the link:

http://www.arvinmeritor.com/contact/contact.asp

This isn't cheap either. I have a reliable mechanic that's done this for decades. The total bill will be near $2K. Obviously not for everyone. However, for our needs it works in the long haul (pun intended). The intention is to get Big Max to cruise at 65 mph more or less and keep the fuel economy. I'm not concerned about acceleration, Big Max never had any neck-snapping G-forces in this department to begin with.