VE Tech

9724VF350

9724VF350

Tractor Guy
I've recently got into piddling with VE's out of necessity, (not having time to wait on shop's) mostly putting seal kits in stock tractor pumps. I've resealed more Roosa Master and CAV pumps than I can count, so while it's not a new experience for me, it's a different pump.

Wondering if anyone that's in the know would mind sharing some info on making them go faster beyond the typical fuel pin, fuel screw, and governor spring.

Some pumps it seems from the factory are 1/2 turn from runaway and max out at ~150 hp, others are 3 turns from runaway and hit 250 (all 12mm). Why? is there some fulcrum lever geometry differences that make a difference?

Different cuts on the distributor end of the rotor. Differences and effect?

The half dozen or so that I've been into all seem to have the same cam plate, I'm told that the pump used on RGT engines have a faster cam plate.

Anything else that I'm not seeing that's important.

I've got a couple 205 pumps to tear into, one of which is for my own engine. Looking for ideas on what changes to make.
 
Not much that I have heard.

Some pumps have solid rollers on the cam plate vs the 2 piece most have.

There are also differences in the regulator.

DV's between the Non-IC and IC pumps are different. The Non-IC is supposed to flow more.
 
Anyone ever find a head that has all 6 feed slots in it instead of just 2? The 6 or so that I looked at all have 2 holes. High RPM fueling would be a lot happier if all 6 were in there.
 
I *think* the runaway screw differences come from how the throttle index is set. That's what I've read anyway for what it's worth.
 
I been through a couple of pumps and don't have any insight. I have spent numerous hours with a few of them on the test stand and didn't gain anything substantial from tweaking this or that. Tried a 4mm cam plate and it broke the ears off and scuffed the rotor. Made awesome flow numbers down low, but flowed way less than a stock cam plate up top. Then it decided to eat itself. Sorry I don't have more to offer.

Stomp
 
I'm planning on getting ahold of one of the stock cam plates out of the Cummins/Iveco RGT engines. They're supposed to be quicker delivery. That's good for obvious reasons, it's also handy when you plan on running a lot of dynamic timing, to help keep discharge passages phased correctly during fuel delivery.
 
Has anybody ever considered this: what if the rotor is jumping the tips or "Peaks" of the rotor at higher RPM's? Rather than actually being able to fully stroke peak to valley at lower RPM's... kinda like valve floating. what if to correct this one were to add stronger springs on the rotor assembly?
So 4mm cam plate and stronger springs...
Has this been done?
 
That's possible. I'd like to address better feed and see what that does first though. Heavier springs are harder on things, but then again if they are floating, that's worse yet. I know how much difference tripling the feed does on a Roosa, I'd think a VE would respond just as well.
 
@3000 rpm that little rotor is trying to make a full stroke 150 times per SECOND. Just to clearify a little more that is 750mm a second. Damn right the rotor is floating on the cam plate.
 
Coolguylevi said:
@3000 rpm that little rotor is trying to make a full stroke 150 times per SECOND. Just to clearify a little more that is 750mm a second. Damn right the rotor is floating on the cam plate.
Click to expand...

Correction, my math was off, that is actually 4500mm/second. Or
177 inches per second.
 
I think some of the small vw stuff has what you are looking for.

I've never personally held one of the locomotive pumps but I hear/read they have some stuff you are looking for.

There is always the option of calling Giles and picking his brain. He gives out some information from time to time.

Case pressure is the issue, as you know. There are some guys having success pushing lots of pressure into the FSS.
 
I beleive that case pressure is only an issue because the vane pump regulating valve opens at higher rpms. Thus not allowing the case to keep a steady pressure. Once the regulating valve opens it reduces the pressure significantly. Where as people feeding the vane pump with more volume/pressure see results at higher rps because it helps feed the vane pump with a little more fuel than the releif valve can reduce.
 
Coolguylevi said:
@3000 rpm that little rotor is trying to make a full stroke 150 times per SECOND. Just to clearify a little more that is 750mm a second. Damn right the rotor is floating on the cam plate.
Click to expand...

Could be, but Cummins produced VE engines that ran 2800 rated speed, high idle would be higher than that.

I'd struggle to believe that they produced engines that close to rotor float. It is possible they had different springs.
 
9724VF350 said:
Could be, but Cummins produced VE engines that ran 2800 rated speed, high idle would be higher than that.

I'd struggle to believe that they produced engines that close to rotor float. It is possible they had different springs.
Click to expand...

Kinda makes ya wonder why cummins goverened these engines at 2800 rmp...
 
9724VF350 said:
Could be, but Cummins produced VE engines that ran 2800 rated speed, high idle would be higher than that.



I'd struggle to believe that they produced engines that close to rotor float. It is possible they had different springs.
Click to expand...


Same pumped used in a VW application runs 4k RPMs. Smaller rotor (10-11mm).

There are better springs and rollers.
 
9724VF350 said:
LOL Hey now, be nice to us simple minded VE folk.
Click to expand...

No I was actually being genuine lol.

I just picked up this early 91 VE truck to resto for a older friend of mine. Pretty much open check book type deal so it's peaked my interest in the VE stuff.
 
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