Governor Spring/VE Info Threads Merged..

[Mutant]

388 Spring Metrics

The metrics are being provided along with www.leespring.com for the DIY folks out looking for answers.



I believe this spring starts defueling around 2000rpm and tops out at 2200rpm.



1464650388

wire diameter 0. 039"

length loop to loop 1 3/16"

wraps of wire 16 1/4

spring diameter 0. 3735

approx spring rate 6. 5 lb/in

approx initial load . 80 lb

 

[bgilbert]

The 388 spring is what comes stock in our trucks.

 

[Mutant]

Test Spring for 4k

Look at http://home.earthlink.net/~bazillion/springs.pdf



This URL provides lots of knowledge about building springs, but I used it solely for how to modify the 374 spring.



Using a 374 spring, I modified it by removing two wraps and then folding out 1/2 of the last wrap to make a new end loop. Now that I have a general idea of which way to go, I have removed it and will find an off the shelf spring that will work. I will likely order a handful and see which one works the best. Just don't hold your breath on a quick report, as my plate is kind of full until spring or early summer.



This modified spring will definitely get you to 4k and possibly higher. I did not see any defueling between 3500 and 4000.

 

[BushWakr - RIP]

Just a quick suggestion here guys... . if yer gonna run those kind of RPM's you need to consider 12 other springs that MUST be changed ... . for our own good so to speak. .



pb...

 

[Greenleaf]

Mutant,



I did the same but with a 366 spring. I don't know what it will turn at but it's scary. It' will not defuel at 3500 rpm for sure. Maybe 4000 rpm's but I'd need a long open road void of any traffic/officers.



I found it nesessary to either pull the slow idle screw out or modify the throttle lever to allow the engine to idle at the normal rpm's

 

[therabbittree]

mumn guys i just modified a 4bt cummins pump to use a vw governor, with the dual spring govenor. . it fit. . and i have a friend running this in his setup . . i will knwo soon... if this fit you could probably make it fit our 6b pumps. . as the 4bt had the same 0ne spring governor... any how its a thought. . i have a extra 6b ve pump i may play with... the throttle shaft bushing had to be changed and swapped with the vw style etc..... all of thsi is in my mechanicl tdi rabbit pickup im building it runs now but this new pump im building isn't installed yet i hope by the end of the week. .

thanks

Deo

 

[dieselcruiserhead]

Does anyone have any advice or information on what the 4BT VE pumps came with stock, for a governor spring? Is it the same as 6 cyls, a 388 spring?

 

[dpuckett]

Does anyone have any advice or information on what the 4BT VE pumps came with stock, for a governor spring? Is it the same as 6 cyls, a 388 spring?

Depends on the RPMs the stock application ran. Some of them topped out around 2000 (many tractors, backhoes, etc) while others ran up close to 3000.



Daniel

 

[therabbittree]

i can check i have 2 apart here and let you know thanks deo

 

[dieselcruiserhead]

Depends on the RPMs the stock application ran. Some of them topped out around 2000 (many tractors, backhoes, etc) while others ran up close to 3000.



Daniel

Automotive spec which as far as I can tell were governed around 2300 to as high as 2500 if adjusted right... The CPL numbers for these models are 858 (non intercooled 105 hp) and 986 (air-air or air-water 120 hp). I am trying to get up to 2800 or even 3000 if possible though I will seldomly run that high... Thanks. .

 

[SKnapp]

so if i were to install a 366 spring this would give me more power? with not having to modify anything else besides setting the idle screws?

 

[Moab4x4]

More power with 366?

KindaSorta. In theory if you get your screws back where you had them your power should be the same at low RPM's. What this spring does is allow higher RPM's before the pump 'defuels'. This would give more power at say 3000 RPM than the stock spring. How many times while passing up a hill would you like to have had more RPM's during that downshift?



My question is..... If you are changing the spring why would you not like to turn a couple of screws, reclock the AFC for more full boost fuel, etc. for more HP in the entire operating range?



Just make sure not to be too aggressive with too many changes at once, It makes it harder to find which one you really took too far. :-laf



Correct me anyone if this is not correct, I just got my 366 installed and it will be a little while before the truck will be put back together.

Thanks,

Ken

 

[Cummins Thunder]

Any of you guys ever wired the spring "closed"?



Take two pieces of safety wire and attach them to the spring so that it cannot expand?



I might just have a little experience with this I performed this on a 92 that was making consistent 18. 1 second passes. After the governor was effectively disabled, the truck started making 17. 0 passes



trucks specs: 92 Extended cab, auto, 2WD, straight piped, ASA intake, line pressure adjusted, and pump tweaked to high hell!!!

 

["Mad Max"]

Fellas, I've been out of the diesel world a while, and wanted to make sure I understand a few things here...



The clarification question I have is this: The 3200 rpm spring allows more fuel through the rpm band which in turn allows the engine to spin a few more rpm's? In other words, at half throttle stock, the engine spins (for example only) 1500 rpm, but with the 3200 spring it would spin higher, say 1700 rpm, and at full throttle unloaded stock the engine spins at ~ 2800 rpm, and with the spring it'd spin 3200 rpm? Is that basically the nature of the 3200 spring, to allow more fuel throughout the entire rpm band?

As well, it seems in stock form I have to floor the actual throttle pedal to really get the coals rolling. Would the 3200 spring make the throttle have more 'results' as you push the pedal?



I will turn up the pump as well as do the injectors to allow the fuel to flow, but I'm more curious what the results my right foot will 'feel' with the higher rate spring?



I appreciate the advise/clarification. I believe every word I read in here, and I just like to know 'how' these mods work so when I do them I know I did it right, and can plan other bombs in the process to see how they all add up.



- M2

 

[Moab4x4]

Keep me honest here all you true experts while I try this one. From what I read here is what I see.

As the governer in the pump spins faster, the weights move a lever causing the fuel to spill earlier causing less fuel to be injected. The purpose being to keep the engine from overreving. As RPMs get near the max determined by the governer the fuel begins to shut down. Kind of like on your gas dragster when you reach the redline, some ignition systems will cause random cylinders to misfire, reducing power, saving your bacon.



The spring in question exerts a force opposite the spinning weights, keeping them from moving outward and spilling the fuel. The theory being that a stronger spring will keep the weights in to a higher RPM before they move outward spilling the fuel.



The post by cummins thunder about wiring the spring so it can't expand would indicate that he no longer has the governer function and has no protection other than his foot from overreving the engine and BOOM.



Some increase the spring strength by cutting off the spring and making it shorter. I bought the 3200 RPM spring which is stronger than the stock one so it allows the engine to rev higher before it defuels.



If you are not at an RPM where the governer is starting to defuel then you should see no difference from the new spring. As you reach RPMs where defueling was starting to happen, but now it isn't you see the kick in the pants.



All this is theoretical as my truck still is not fully assembled. Does anyone have any practical experience to correct my "book learning"?

 

["Mad Max"]

Ahhh, okay I think I understand now. So, with just a spring install, there isn't a power increase but rather a higher rpm range to get more legs in each gear. That makes good sense.

Thanks.

- M2

 

[Sri Ram]

(Sorry if this has been addressed already. ) Is there no danger, then, of over-revving?

 

[dpuckett]

depends on what you define as over-revving. If 3500-3800 no load RPMs is over-revving, then yes, you can over-rev (I had a 91 that turned 3600+ no-load- never floored to see the top end). If you define it as a run-away condition, where the RPMs wont come back down out of orbit, then that depends on other fuel settings.



ACtually, most things performance wise depend on fuel settings. My 91 would pull to 3100 RPM or so with the stock internals, high idle screw backed all the way out. It would eventually reach 3200-3300 under load, but it took a while to get that last 200RPM.



Now, I have heard (read) that guys have noticed a better bottom end, which makes sense, due to the new spring pulling harder to oppose the governor weights and not letting them fan out as fast ( the fanning out will slow it down). So, you *MAY* reach your peak RPM in the same time, but since it is a higher RPM than stock, you get to X- RPM faster than wtih stock. This also depends on vehicle weight, gearing, etc, etc.



-DP

 

[Sri Ram]

I meant 'over-revving' as runaway and as "undue" engine wear.

 

[Moab4x4]

Governor spring asssembly

Tonight I was all thumbs trying to get that spring to hook to the tophat without making it fly many different directions.

The lever where the hole is that the tophat sits in has a slot to the top of the lever. I was able to assemble the spring /tophat assy and then the 366 spring slid down the slot and then the tophat just popped in.



The top of the pump is lots easier to get set in the right position if #1 the full fuel screw is fully backed out and #2 the AFC guide pin is protruding into the bore. ( IE the fuel pin and diaphram have not been installed yet)



Just another assembly option if the main one doesn't seem to work well today.



Good Luck and if you haven't done this yet, I don't know if there is a better bang for the buck available.

Ken