More Rpm-fuel Help For Me

[scooter]

I read the other topic on how to increase the fuel but my pump looks different. I think it is a Bosch.

Its a ETAY673A 315 HP 1979, Max rpm under a heavy load is only 1900 and cruzing is 2100 I can only due 57 mph at

2100 rpm I need just a little more! The puff elemator works great and I have a bypass s/w on the dash for steep hills

The engine doesn't blow smoke at all.

Ok i opened the top of the pump and ????? New photo too!!

Thanks

Edited December 10, 2007 by scooter

[GearheadGrrrl]

I believe 1900 RPM was the normal full power governor cutoff with that engine, with no load cutoff of about 2100 RPM. You can probably adjust the governed speed up a bit, but the 673 is only good for about 350 reliable horses so I wouldn't up the fuel rate too much. BTW, is that an aluminum frame I see?

[ThaddeusW]

Hey scooter what transmission and rear ratio do you have?

Nice Mixer by the way.

[MACKS]

Hay scooter-I have the same motor in my 83 rd dump with a 12 speed mack tran, I'm not interested in turning up the fuel, that might give it more power but it's not gonna do much for the rpm, even with the puffer shut off there is no difference in rpm, I have the throttle screw turned all the way in so I can reach 21 or 22 hundred rpm with a load but the problem is it takes to long the hit 21 hundred, it fells like the govener starts shuting it down at around 17 hundred and then it's a slow climb to 21 hundred, it makes the truck run flat with no push off between gears if you know what I mean. I think we need to adjust the govener but I don't know how, does any one here know how to do it. I was even thinking of putting a different pump on it but not sure witch one would do the trick.Can any one here help us out.

[scooter]

Hey scooter what transmission and rear ratio do you have?

Nice Mixer by the way.

I have the Maxi-Torque T107 5 speed and I think the rear ends are 4.11.

4th to 5th is a lugger on a hill but it pulls through it from about 1000 rpm, if I shift with the jake it cuts back a little smoking and

keeps the boost up.

Here is a photo from 6 years ago when I put a new clutch in it. Dam that thing was Heavy

[HK Trucking]

I have the Maxi-Torque T107 5 speed and I think the rear ends are 4.11.

4th to 5th is a lugger on a hill but it pulls through it from about 1000 rpm, if I shift with the jake it cuts back a little smoking and

keeps the boost up.

Here is a photo from 6 years ago when I put a new clutch in it. Dam that thing was Heavy

4.17 would be the Mack ratio.

The TRL107 5 speed is direct in 5th.

That trans with 4.17 rears on 10:00 20 (or 11R22.5) rubber will give 62 MPH @ 2100 RPM.

I had a few with the TRXL107 6 speed which is also direct in high gear and that's what the top speed was.

When the speed limit got raised to 65, I raised the high RPM to 2300 to squeeze a little more out of em.

[HK Trucking]

BTW, that trans in the photo is a TRXL 107 or TRXL 1071 6 speed.

I can see the shift rail for the compound on top of it.

[HK Trucking]

I read the other topic on how to increase the fuel but my pump looks different. I think it is a Bosch.

Its a ETAY673A 315 HP 1979, Max rpm under a heavy load is only 1900 and cruzing is 2100 I can only due 57 mph at

2100 rpm I need just a little more! The puff elemator works great and I have a bypass s/w on the dash for steep hills

The engine doesn't blow smoke at all.

I just re read the original post in this thread.

That 300 plus engine is not designed to work with the 5 or 6 speed transmission with it's 900 RPM spread between gears.

The 300 plus was designed to be used with a closer ratio transmission such as a TRTXL1070 12 speed or a 9, 13, or 18 speed in order to keep it in it's operating range.

I noticed that your truck is an RLST 685. That would denote that it originally came with an ENDT675 237 HP Maxidyne engine.

The root of this problem is an incompatible engine / transmission combination.

Perhaps you could swap a pump and injectors from an ENDT676 285 Maxidyne onto your engine and that would give it the wider operating range needed to pull from 1200 to 2100 RPM, the way that 6 speed is set up.

[b61mack]

I read the other topic on how to increase the fuel but my pump looks different. I think it is a Bosch.

Its a ETAY673A 315 HP 1979, Max rpm under a heavy load is only 1900 and cruzing is 2100 I can only due 57 mph at

2100 rpm I need just a little more! The puff elemator works great and I have a bypass s/w on the dash for steep hills

The engine doesn't blow smoke at all.

Ok i opened the top of the pump and ????? New photo too!!

Thanks

The picture you had yesterday shows you have a robert bosch pump, there is a plug on the back side of the pump, take the plug out have someone turn the engine over by hand with the fuel stop out, there are 2 flat screwdriver ajustments on the goveneor half way around from each other. you have to turn them same turns on both sides, you have to use a long flat screwdriver through the exaust manifold, push down while you turn. i would go 3 turns to start with each one. i turned the rpm up on a 88 300 went from 1750 to 2200. hope this helps let me know. Ron

[scooter]

The picture you had yesterday shows you have a robert bosch pump, there is a plug on the back side of the pump, take the plug out have someone turn the engine over by hand with the fuel stop out, there are 2 flat screwdriver ajustments on the goveneor half way around from each other. you have to turn them same turns on both sides, you have to use a long flat screwdriver through the exaust manifold, push down while you turn. i would go 3 turns to start with each one. i turned the rpm up on a 88 300 went from 1750 to 2200. hope this helps let me know. Ron

Ill try that when I have to do some exhaust wk, its Tight in there dont know if i can cut the safety wire and get the plug out.

I found 2psi of boost!!! the gas pedal had a little more travel in it . I'm up to 27 psi now