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Engine Specific Info and Questions => IDI Engine => Topic started by: 32 VALVES on December 03, 2009, 07:27:01 pm

Title: GOVERNOR MOD
Post by: 32 VALVES on December 03, 2009, 07:27:01 pm
Why is the thread for the mod not have pictures on it, I need pics before I dig into this pump.  I have a 1Z tdi motor with a AAZ turbo pump and need alittle more power up top mine seems to run out of steam..
Title: Re: GOVERNOR MOD
Post by: 745 turbogreasel on December 03, 2009, 09:51:06 pm
I happen to have this page open ;D
http://forums.vwvortex.com/zerothread?id=3107325 (http://forums.vwvortex.com/zerothread?id=3107325)
Title: Re: GOVERNOR MOD
Post by: Rabbit on Roids on December 04, 2009, 12:16:12 pm
only shim the MAIN SPRING!!!
Title: Re: GOVERNOR MOD
Post by: vanbcguy on December 05, 2009, 04:09:50 pm
only shim the MAIN SPRING!!!

X20000000000000!
Title: Re: GOVERNOR MOD
Post by: ScottyTD on January 09, 2010, 10:27:27 pm
I was reading the thread on vortex and its very thorough and great pictures.  What I was wondering about was what do you mean by "only shim the MAIN SPRING", your not removing it but compressing it more right?    It shows a thick washer, could you just use a few small ones instead? 
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 09, 2010, 11:00:40 pm
I have read up a bunch on this, and also would like to know for absolute clarification, which springs get shimmed and why this is so.

I have heard that people shim the main, some shim the intermediate.. when each other swear against the opposite method.. Why?
Title: Re: GOVERNOR MOD
Post by: theman53 on January 09, 2010, 11:07:09 pm
x 3  .....

(http://www.66rover.com/TDIswap/TDI%20Parts%20121307/slides/PICT1779.JPG)

It is missing the littlest spring in the pic, but the biggest spring on the left is the main spring. Put 1/4" of washers in it and let it rip. If you shim the other springs you will have driveability issues. If you shim/eliminate the intermediate spring it will have dead spots in the middle RPM ranges and have weird pedal feel on hills. JUST SHIM THE MAIN SPRING AND BE HAPPY :D. Good luck.
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 09, 2010, 11:11:07 pm
Lucas, it looks as though the main spring controls over all fueling? whereas the other two have there own area of fueling?

what is the main springs job in the governor? to allow slow linear rise of fueling? shimming it makes it a quicker rise? What if you go bigger than 1/4"? better or worse?
Title: Re: GOVERNOR MOD
Post by: theman53 on January 09, 2010, 11:33:15 pm
more than 1/4??? Never tried it really.Well mine was probably 5/16. I heard some have  just put a solid piece in there???

What I noticed was when you mash it in first you had to shift before you thought it was going to blow. 2nd same, 3rd same. It would keep pulling as long as the rpms were still climbing. 4th and 5th usually were way over the speed limit and still pulled well, not quite as good as the lower gears.

From what I gather the main spring compresses a little on low RPM, but mainly it is the higher RPMs that it affects. I never had a tach, but I am guessing about 2,500 the main spring starts to limit fuel and will continue until 4,800-5,300. Then I don't believe your engine will rev anymore because of lack of fuel. You should feel it when driving that you lose power even though the engine keeps spinning faster. When you mod it it will go until valve float...or at least that is what is sounded like to me.  ;)
Title: Re: GOVERNOR MOD
Post by: RadoTD on January 09, 2010, 11:53:54 pm


From what I gather the main spring compresses a little on low RPM, but mainly it is the higher RPMs that it affects. I never had a tach, but I am guessing about 2,500 the main spring starts to limit fuel and will continue until 4,800-5,300.

Does the main spring really start at that low RPM? I remember seeing a dyno comparison between a stock pump and Giles (N/A 1.6) and IIRC, the curves were very similar until about 1000rpm before he backed off. Maybe the main spring came on too smoothly and I didn't notice what I wasn't looking for?

I'll see if I can dig it up again...

*Edit* Found it here... http://www.vwdiesel.net/forum/index.php?topic=14734.15 (http://www.vwdiesel.net/forum/index.php?topic=14734.15)

Looks to me like the main spring kicks in around 3300rpm on that stock 1.6... might be closer to 2500 on a 1.9. I'd better get on that gov mod for my car! :)
Title: Re: GOVERNOR MOD
Post by: ScottyTD on January 10, 2010, 12:04:13 am
wow Theman53 thanks for the clarification !!!!
Title: Re: GOVERNOR MOD
Post by: wolf_walker on January 10, 2010, 02:24:56 am
As I read it the Bosch book says above idle the intermediate spring is the one in play.
It's really a beautiful system.
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 10, 2010, 02:31:04 am
As I read it the Bosch book says above idle the intermediate spring is the one in play.
It's really a beautiful system.

See! mixed answers LOL! I think we need a definitive answer here.. :P Bosch says its the intermediate spring, but people have luck with the main? weird eh?
Title: Re: GOVERNOR MOD
Post by: theman53 on January 10, 2010, 07:55:03 am
yes above idle it is the intermediate spring doing much of the work...but you need it to. If you shim it or put a solid piece in it will cause driving issues. If you hold the pedal in one spot and the intermediate spring has a different load put on in *rolling hill for ex.* then your rpm will go up then down without moving the  pedal at all. It feels like you don't have a direct connection to the car it does what it wants. I suspect the firmer the intermediate spring the worse it would be.

MAIN SPRING FTW!!!(http://www.fullsizebronco.com/forum/images/smilies/rockon.gif)
Title: Re: GOVERNOR MOD
Post by: vanbcguy on January 10, 2010, 06:35:21 pm
Main spring is the high RPM cutoff, if you're trying to raise your fueling cutoff it's the one you want to shim (or even better find a stiffer spring!!)

Intermediate spring makes the car driveable.  Without it you'll have a REALLY hard time driving the car.  Its total movement is practically nothing compared to the main spring too so it really isn't "limiting" anything.

During normal driving the Intermediate spring is what is controlling the car - you NEED it to though.
Title: Re: GOVERNOR MOD
Post by: Alcaid on January 10, 2010, 06:42:10 pm
So how much shimming of the main spring is needed for a 6k rpm engine? 1/4", 5/16", more, less?
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 10, 2010, 07:31:10 pm
I have another thread roughly about the same thing, and I was told that these engines will reach and sustain 5350 +/- 20 floored in neutral. These engines could run forever at 5300rpm, they are built like tanks.

When shimming even small amounts of the main spring, such as the 1/4" results in fueling way higher in the rpm range.. if no shims on a stock pump and engine result in 5300rpm floored in neutral.. i think adding a 3/16" shim would make the governor react a lot better to pedal movement.

Does anyone have a tach, and an engine that has been shimmed with a small shim on the main spring only? What was your maximum rpm achieved?

This is something I definitely want to experiment with when i dig the diesel out in the spring.
Title: Re: GOVERNOR MOD
Post by: wolf_walker on January 10, 2010, 10:31:06 pm
I have another thread roughly about the same thing, and I was told that these engines will reach and sustain 5350 +/- 20 floored in neutral.


Isn't the Bentley procedure to set full throttle RPM in part with the full throttle stop screw to whatever the stated max rpm for the given motor is?  It's lower on the hyd motors seems like, they are all somewhere around 5K.


I have another question along these lines.  Am I the only one that almost never floors these things?  I have never had one, out of half a dozen or more, all stock pumps mind you, that accelerated any faster at WOT than they did at half or maybe 3/4.  Some of them smoked more with more throttle, but beyond a point they just don't do any more on a stock pump.  This is NA mind you.
I always thought it was odd people saying to tweak on the full load screw, and I never bother since I seldom hit it.
What I'd like is, what feels like, less fuel cut at moderate but not FULL throttle.  If that makes any sense.
Title: Re: GOVERNOR MOD
Post by: burn_your_money on January 10, 2010, 11:19:18 pm
I almost never hit full throttle, to be honest I don't think I go past 1/2 throttle.
Title: Re: GOVERNOR MOD
Post by: gldgti on January 11, 2010, 06:40:06 am
I have another thread roughly about the same thing, and I was told that these engines will reach and sustain 5350 +/- 20 floored in neutral.


Isn't the Bentley procedure to set full throttle RPM in part with the full throttle stop screw to whatever the stated max rpm for the given motor is?  It's lower on the hyd motors seems like, they are all somewhere around 5K.


I have another question along these lines.  Am I the only one that almost never floors these things?  I have never had one, out of half a dozen or more, all stock pumps mind you, that accelerated any faster at WOT than they did at half or maybe 3/4.  Some of them smoked more with more throttle, but beyond a point they just don't do any more on a stock pump.  This is NA mind you.
I always thought it was odd people saying to tweak on the full load screw, and I never bother since I seldom hit it.
What I'd like is, what feels like, less fuel cut at moderate but not FULL throttle.  If that makes any sense.

in a n/a car, this is all completely understandable - you just dont have any go... that last 1/4 of the throttle movement really doesnt do much.

a turbo car is quite a different thing altogether :-D
Title: Re: GOVERNOR MOD
Post by: regcheeseman on January 11, 2010, 07:49:24 am
I beg to differ on this issue  ;D

I've always tended to remove the intermediate and preload the main for a bit more rev ceiling - but then I use a 1mm preload.

In the other camp are those who shim 6mm into the main only. I can understand their reservations about driveability but 6 :o mm preload is a hell of a lot.

After studing the linkage in depth - i'd probably go for the main spring in future, but not as prescribed.....
Title: Re: GOVERNOR MOD
Post by: Rabbit on Roids on January 11, 2010, 11:57:53 am
I beg to differ on this issue  ;D

I've always tended to remove the intermediate and preload the main for a bit more rev ceiling - but then I use a 1mm preload.

In the other camp are those who shim 6mm into the main only. I can understand their reservations about driveability but 6 :o mm preload is a hell of a lot.

After studing the linkage in depth - i'd probably go for the main spring in future, but not as prescribed.....

i shimmed 5 or 6 mm, and it works great. the governor on it now lets me turn more rpms than my gas GTI.
Title: Re: GOVERNOR MOD
Post by: regcheeseman on January 11, 2010, 12:13:26 pm
Quote
i shimmed 5 or 6 mm, and it works great. the governor on it now lets me turn more rpms than my gas GTI.

Any reason for this rather than simply replacing the main spring with something solid?
Title: Re: GOVERNOR MOD
Post by: wolf_walker on January 11, 2010, 07:53:59 pm
So...      Does the gov mod have any effect at part throttle accel?

I don't have my head around how this thing works yet even after a lot of reading.
Title: Re: GOVERNOR MOD
Post by: Rabbit on Roids on January 11, 2010, 08:59:41 pm
it allows for more fuel at higher rpms...
Title: Re: GOVERNOR MOD
Post by: theman53 on January 11, 2010, 10:10:33 pm
I think of it as a "wave" in an aquarium. All the springs will compress at the same time a little bit and push on eachother. Basically, every action opposite and equal reaction. By making the main spring stiffer it will fight the advance of the governor weights more. That will keep more fuel in the injection. The main spring unmodded has some overlap with the other springs, when it is stiffened it doesn't and fueling at all RPMs is a little better. ----That is the way I see it working in there for those wondering.

I don't know what a solid piece will do. I wanted a little bit of rev control. I liked what I did...you could experiment and tell us if it works or not :D
Title: Re: GOVERNOR MOD
Post by: regcheeseman on January 12, 2010, 07:35:00 am
Quote
...you could experiment and tell us if it works or not


That's the problem, many have experimented and they all have the best solution  ::)

Your logic makes perfect sense but the overlap between the two springs is not at all linear, the intermediate, being light and very short travel (0.8mm IIRC) tends to act as a damper more than a governer. The main spring, being much heavier only really starts comes into play when the intermediate is fully compressed.

However I think that retaining a degree of springiness may be a good idea at the very top end, but when talk is made of large shims, surely the main is nearly coilbound anyway? Hence others just fitting a solid spacer and job done...
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 25, 2010, 01:32:38 am
Sorry to dig this one up, but it needs for sure clarification.  ;)

However I think that retaining a degree of springiness may be a good idea at the very top end, but when talk is made of large shims, surely the main is nearly coilbound anyway? Hence others just fitting a solid spacer and job done...

What exactly would shimming the main completely do? Because in some pictures..

This picture clearly shows that the main spring only has about a few mm of travel before the two spring seats meet.
(http://i299.photobucket.com/albums/mm307/J_holubek/IMG_3027.jpg)

This picture shows that three small washers easily takes up all the space and eliminates the main spring.
(http://i299.photobucket.com/albums/mm307/J_holubek/IMG_3029.jpg)

This picture shows a solid shimmed main, and roughly 4mm of shim on the intermediate spring..
(http://i299.photobucket.com/albums/mm307/J_holubek/IMG_3032.jpg)

It looks as though the main spring is completely out of the equation without any shimming at all, as 3mm disables it. the intermediate spring is then shimmed with 3-4mm itself, and looks as though before being completely coil bound it can only move around 3mm.

It is almost a solid governor! Would this car have had driving problems? The intermediate spring looks fairly strong, this car would rev in almost an instant... from what it looks.

So my question is, what is the best method? From what I can see, the main spring only moved 3-4mm.. shimming it that far disables its function... shimming the main spring anymore than that would effectively be putting a pre-load on the intermediate spring.. as the left side seat is stationary to the cage.. it can only go left and compress the intermediate spring...

I (among many other I'm sure) am looking for a definite answer as to what the correct shimming is for best driveability/performance factors.. I have an old pump here, I may tear it down tomorrow and do some investigating on the Governor cage.. but won't be able to install it to test it on a running engine.
Title: Re: GOVERNOR MOD
Post by: Rabbit on Roids on January 25, 2010, 10:19:34 am
thats wrong. its not gonna run right. period. this is one of those on going things. most people shim the ingetmediate spring, but you need to shim the main. the intermediate is the spring the pump uses for driving around and stuff (not idle, but not WOT either) and the main spring is the one that actually is used in high rpms and to cut fuel. you get hanging idle, and all sorts of driveability problems doing the intermediate.

and in those pics, thats NOT the main spring.

it goes:
1.) idle spring
2.) intermediate spring
3.) main spring

and the main spring is closest to the throttle shaft.. the idle spring is the one on the end thats outside the cage.

either way, 2 stainless nuts (1/4") under the main spring works just like a stock governor but it turns 7000. lol.
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 25, 2010, 11:29:43 am
My bad Kevo, thanks for clearing it up  ;D

So in my pics is what NOT to do or you WILL have driveability issues with a solid shimmed INTERMEDIATE spring.

This pic (from a considerable consensus) is the proper method on how to do the "Governor Mod" correctly! Sorry for the confusion in my last post! lol This will effectively allow the pump to feel that it has a stiffer main spring and allow for more fuel at all rpm ranges under load.

(http://i299.photobucket.com/albums/mm307/J_holubek/IMG_3027-2.jpg)

p.s are there actually any definitive DIY's out there that properly outline the steps needed and the correct shims to put in the correct spots? lol
Title: Re: GOVERNOR MOD
Post by: Rabbit on Roids on January 25, 2010, 12:06:01 pm
there are FAQ's but people just dont know what spring to shim most of the time.

but that pic you posted up this time, its perfect. thats the way to do it.

we really need to clear up the confusion about governor mods in the FAQ...
Title: Re: GOVERNOR MOD
Post by: dts67 on January 25, 2010, 03:07:29 pm
If you take the lever in both hands and pull it youll see how it works, at WOT the 2 smaller are fully compressed anyway, shimming them makes no gain imo, only ruins part throttle and idle control.
Title: Re: GOVERNOR MOD
Post by: vanbcguy on January 27, 2010, 01:34:46 pm
My bad Kevo, thanks for clearing it up  ;D

So in my pics is what NOT to do or you WILL have driveability issues with a solid shimmed INTERMEDIATE spring.

This pic (from a considerable consensus) is the proper method on how to do the "Governor Mod" correctly! Sorry for the confusion in my last post! lol This will effectively allow the pump to feel that it has a stiffer main spring and allow for more fuel at all rpm ranges under load.

p.s are there actually any definitive DIY's out there that properly outline the steps needed and the correct shims to put in the correct spots? lol

DING DING DING!  We have a winner!!

Hope you don't mind but I've copied the pic and stuck in on my own server so there's another one out there (seems people's Imageshack links always go dead by the time I want to read the articles again) - so for posterity and all you future thread searchers here's the pic again just in case:

(http://nashira.ca/Members/bhughes/vw/pics/propergov.jpg)
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 27, 2010, 09:27:47 pm
Np Vanbcguy. MIGHT I SUGGEST copying this entire thread I have put together to your server as well.

http://www.vwdiesel.net/forum/index.php?topic=24323.0 (http://www.vwdiesel.net/forum/index.php?topic=24323.0)

I took all the broken threads on here and vortex.. all the pictures describing the best method.. and information from other sources as well, and compiled them in to a nice little thread in our FAQ section :)
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 27, 2010, 09:42:58 pm
Does anybody have experience with what will happen when shimming the main spring with something solid?

There was question raised.. and i wish to find an answer for it for my governor thread :)

TIA!
Title: Re: GOVERNOR MOD
Post by: dts67 on January 28, 2010, 08:39:01 am
(http://i670.photobucket.com/albums/vv66/del635/th_P2240028-1.jpg)
This pic any good? Theres loads more random pump part pics on my photobucket for anyone wanting to use them, 'del635'.
Shimming the governor solid, messes up the lda? ie no smoke control?
 
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on January 28, 2010, 12:48:30 pm
(http://i670.photobucket.com/albums/vv66/del635/th_P2240028-1.jpg)
This pic any good? Theres loads more random pump part pics on my photobucket for anyone wanting to use them, 'del635'.
Shimming the governor solid, messes up the lda? ie no smoke control?
 

How many mm's of washers would you say you added to the Main spring on the right? How is it to drive? any irregularities on acceleration, cruising, up hills? Good power through the entire RPM range? seems, you've almost got the main srping shimmed right solid..

I am very interested to hear of your experience with it this way. :)
Title: Re: GOVERNOR MOD
Post by: dts67 on January 28, 2010, 02:37:40 pm
No problems at all at part throttle at any load, the rpms do not hang at all either between gears. There is still travel in the main spring, cant remember exactly how much tbh maybe about a 1/4 of original and there is also much more tension, I thought this was needed for the lda otherwise there would be nothing for it to hold back on off boost. The cars pulls harder above 3k rpm at full throttle much different to the non shimmed lever where power just tailed away to nothing.
I used to have the smaller spring shimmed as well there was no noticable power difference at full throttle and at part throttle it was hard work keeping the car at a constant speed, you had to constantly adjust the pedal back forward it was only after this did I really understand just what the governor is doing at all rpms/loads its not just a rev limiter.
The one thing I dont like about the gov mod is the lack of no load speed limitation, eg I was trying to pull another car which was stuck in snow and when my wheels lost grip a quick blip of the pedal saw over 6k rpm! :o I cant let anyone drive my car either as it would take a matter of seconds to blow the engine to pieces but all in with a bit of sense it is an excellent mod for free hp.
Title: Re: GOVERNOR MOD
Post by: gldgti on January 29, 2010, 03:25:49 am
good point about having no rev limit at all - and others driving your car...

i guess it wouldnt be a huge job to wire a relay into the stop solenoid, trigerred by an electronic overspeed signal (either from tach or something else). cut fuel at specific rpm.....
Title: Re: GOVERNOR MOD
Post by: professor on February 06, 2010, 03:03:23 pm
i guess it wouldnt be a huge job to wire a relay into the stop solenoid, trigerred by an electronic overspeed signal (either from tach or something else). cut fuel at specific rpm.....
how do we do that? anyone do this? anyone have an electric scheme of that?
thks
Title: Re: GOVERNOR MOD
Post by: Rabbit on Roids on February 06, 2010, 03:30:13 pm
(http://i670.photobucket.com/albums/vv66/del635/th_P2240028-1.jpg)
This pic any good? Theres loads more random pump part pics on my photobucket for anyone wanting to use them, 'del635'.
Shimming the governor solid, messes up the lda? ie no smoke control?
 

im about this far shimmed up too. (~3/16") i really cant tell any difference driving the car, other than it has alot more power and turns about 7000 rpms after the mod.

it blew alot more blackness after the mod.
Title: Re: GOVERNOR MOD
Post by: gldgti on February 08, 2010, 03:04:54 am
i guess it wouldnt be a huge job to wire a relay into the stop solenoid, trigerred by an electronic overspeed signal (either from tach or something else). cut fuel at specific rpm.....
how do we do that? anyone do this? anyone have an electric scheme of that?
thks

let me think on it a while, i'll get back to you :-)
Title: Re: GOVERNOR MOD
Post by: professor on February 20, 2010, 09:03:53 am
i guess it wouldnt be a huge job to wire a relay into the stop solenoid, trigerred by an electronic overspeed signal (either from tach or something else). cut fuel at specific rpm.....
how do we do that? anyone do this? anyone have an electric scheme of that?
thks

let me think on it a while, i'll get back to you :-)
hi
don't forget this ;D
thanks
Title: Re: GOVERNOR MOD
Post by: kaneb on February 20, 2010, 05:40:11 pm
I just did mine today.  I'll see how it turns out once i have the engine in the car.  Except i shimmed mine at the end of the main spring.  Like in the photo above to your far right.  Hope it works out, am strongly thinking i'm going to want a tach for this thing.

Kane
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on February 20, 2010, 10:38:16 pm
to bad you didn't wait till after you had the engine in, could have saw the gains on the butt-dyno lol

How did it go? did you use a new seal for the pump top?
Title: Re: GOVERNOR MOD
Post by: kaneb on February 20, 2010, 11:04:41 pm
Was easy to do.  Was planning on waiting till the engine was in the car. Then decided when cleaning up the pump i would just do it today.  Didn't use a new seal mine should be fine, if it leaks then ill get the new seal kit.

Title: Re: GOVERNOR MOD
Post by: professor on March 02, 2010, 06:23:56 pm
i guess it wouldnt be a huge job to wire a relay into the stop solenoid, trigerred by an electronic overspeed signal (either from tach or something else). cut fuel at specific rpm.....
how do we do that? anyone do this? anyone have an electric scheme of that?
thks

let me think on it a while, i'll get back to you :-)
hi
don't forget this ;D
thanks
 ::) ::)
Title: Re: GOVERNOR MOD
Post by: fatmobile on March 02, 2010, 09:40:31 pm
I removed the smaller spring and put a 1/16" thick washer in it's place.
 the governor still works and the power through the midrange and upper end increased.
Title: Re: GOVERNOR MOD
Post by: 8v-of-fury on March 02, 2010, 09:42:02 pm
I can't wait to do this mod! IT IS GETTING CLOSE TO THAT TIME :)

I think I will shim about.. as much as I can. or maybe be conservative?

Has anyone tried small shim and then went more shim? was there any increase in power? butt dyno readouts? increase in smoke? EGT's?
Title: Re: GOVERNOR MOD
Post by: zukgod1 on March 03, 2010, 06:53:22 pm
I usually replace the main spring with a solid piece of tubing and leave the intermediate alone.

Runs great, no de-fueling at all..

I've built a pump or two just for reference..   8)