#3 Povo update

[Des]

Ah, but Michel. Hobart's roads are the smoooothest in all of Oz. No need to compensate for the cobble stones of the Champs-Élysées.

really?

They aren't that special,

"thinks of a massive pot hole on the major highway into the city that has been there for atleast 2 years"

 

[Michel]

"thinks of a massive pot hole on the major highway into the city that has been there for atleast 2 years"

Potholes are extras....

 

[SELfor50]

Nice work o-man...love those twin thermos!!
How's the search for wheels / tyres going?

 

[oscar]

Nah, no real advancement there. 15" penta look-a-likes will probably go on and.... yeah I still don't know what tyre to use. Maybe cheap sub $100 tyres will make me a better driver. I'll have no confidence in them, will reach their grip limits quickly and will learn very quickly how to keep a w116 squealing without running into the kitty litter.

The sane side of me wants to throw a new set of A048's on the credit card.

 

[SELfor50]

Nah, no real advancement there. 15" penta look-a-likes will probably go on and.... yeah I still don't know what tyre to use. Maybe cheap sub $100 tyres will make me a better driver. I'll have no confidence in them, will reach their grip limits quickly and will learn very quickly how to keep a w116 squealing without running into the kitty litter.

The sane side of me wants to throw a new set of A048's on the credit card.

Hahah... I say go the cheapies!! It'll make the first event or 2 feel much more 'eventfull'!

Of course, a new set of A048's... you'd never look back!

 

[oscar]

Been over a month since the last update but in that time I got a boxful of parts then some. Most are little easy bits but out of all the things to be done, today was eventful with new tyres and and wheel alignment done. My only disappointment is that the steering in a straight line is still very floaty. The more I played with things tonight made me realise it's the play in the steering box. Way too much movement. Whilst I've got a kit to reseal the box I think I'll just swap it out if I can't adjust it in situ.

Here's what else has been done.

Bushes for transmission levers. There was nothing left of the old ones. Before and after shot. Still have to change gear oil to a thinner one.

The first pic below is an older one of the wooden gear lever and collapsed covering. I preferred something more grippy so I just bought original.

Left upper control arm was suspect. Inner bush was rooted and the ball joint had a bit of play. Replacing this arm alone led to a big improvement in stability whilst driving.

Lastly, new tyres. Whilst I wanted r-specs then was going to get Yokohama S-Drives on account of affordability but I was severely accidentally underquoted for the S-Drives. Then these Pirellis came along. The Pirellis are virtually unused (600-700km travelled) off a new car that ended up with Michelins. These tyres are Pirelli P Zero Nero 235/40ZR17 (90Y), all four for $640AUD. I was originally going for 45 series Yoko S-Drives but figured a 40 series tyre would give just a tad more acceleration. It didn't feel too different to be honest. (Maybe I should use the accelerator more ). You can see the difference in height from a 14" tyre below. 45 series on the other hand have virtually the same diameter as the stock 14"s.

 

[SELfor50]

It's really quite sexy seeing new control arms installed!!!

It still sorta looks like a 4x4 though. Start chopping my friend!!!

 

[oscar]

It still sorta looks like a 4x4 though.

I know. WTF!!! It sits so high but it's pretty stiff suspension. I'm worried about cutting though. I found old posts that made me think twice about it, how it affects steering, handling, spring rates. In other words, doing what you've done is the way to go. Fresh out of $ to do anything about it yet though.

 

[Michel]

I think it looks great in the pics...

Will it make it to Oran park?

 

[oscar]

Will it make it to Oran park?

It'll definitely make it to OP. It's being trailered/dragged, either way it's coming whether it likes it or not.

Even I'll admit it looks pretty good in that last photo. The paint looks fantastic when seen in light like that, but it's not really that good. You'll see when you see it in person (metal) but it's so bad you'll make a slow retreat afterwards and take all those offers of apprenticeships with you.

 

[B13]

What will help the paintwork is some appropriate decals carefully placed around the body (over the pain drips).

Re. Carby problem - octane boost is your friend - Cam swears by it.

Are you intending to shoot lots of video footage of the day and all the MBs?

Ian.

 

[oscar]

What will help the paintwork is some appropriate decals carefully placed around the body (over the pain drips).

You bet! I'm planning on it, my watch list on ebay is full of decals and has been for weeks. Looks like I'll have to scrub Yokohama and add Pirelli. BTW, the Pzeros are made in Germany. COOL

Are you intending to shoot lots of video footage of the day and all the MBs?

Hell yeah. My camcorder and Nokia wont be turned off. I reckon everyone else will be the same. If not, I'll make up for it Just gotta jig something up for the headrest.

Re. Carby problem - octane boost is your friend - Cam swears by it.

Not disagreeing but something else is happening. Check out POVO with Jake Brakes Everytime I floor it, I loose power and it sounds like Jake Brakes are pulling me up.
Annoying eh? I can't test out the new tyres properly and my speed is limited to 135km/hr in 4th. Press the accelerator just that little bit more and Brrrrrrrrrrrrrrrrrrrrr

 

[B13]

To quote Dr. Nick Rivierra: "What the hell is that?"

 

[B13]

Ok 1st things first, you're probably sick of spending money already but you probably noticed both my race cars have a big fuel pressure gauge right in front of the drivers line of sight... EVERY race car should have a fuel pressure gauge and its even more critical with carby engines because of the low pressure the system works and the way the fuel can slow around in the tank, a pressure gauge is the only way to "see" as opposed to "feel" fuel surge.

My preference is for Autometer, but Speco make a decent product so look for one of these:

http://cgi.ebay.com.au/Speco-2-Fuel-Pressure-gauge-15-PSI-NEW_W0QQitemZ250309660692QQihZ015QQcategoryZ33674QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Then again since MBs come with VDO instruments it makes more sense to install VDO items on Povo so try to find one of those 0-15PSI.

Getting back to the Solex, I believe they have some thingy on them which stops the car being revved out if it things the engine is cold... maybe thats playing up. Also if the solex has a choke flap on the top of the primary barrels maybe just remove it and see if the problem is related to that closing as you go to rev it out... you don't really need it if you can work out how to get the car started without the choke...

If its only about an hour to fit the holley, I would go to the turd brown car, charge the battery and get it running on the holley, take time to really get the engine nice and warm and confirm it runs as well as expected on that engine, and revs out all the way to the tacho red-line or slightly over without over lean/over rich situations / misfires etc. Maybe even remove the engine fan and see how the carby behaves when the coolant goes well into the high 110+ degree mark. What you're aiming at is to decide whether the Holley will be transferable to Povo without being re-kitted... that will save time and money. If it does come up trumps, I wouldn't spend too much time on the solex, and just chuck on the Holley. You'll also need a pair of these when complete:

http://cgi.ebay.com.au/HOLLEY-STICKERS-PACK-OF-5_W0QQitemZ320312221464QQihZ011QQcategoryZ33549QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I.

 

[oscar]

Would love Holley stickers. There's no Solex ones and why should there be. They're nothing to boast about. Well, everything was working beforehand.

I've got the m110 manual and there's plenty of info on the handful of versions of the Solex used. I'll see if there's any clues but I wasn't aware of the over-reving cutout.

I had wondered about fuel starvation and the fuel pressure gauge is a good idea. Povo has a relatively new fuel pump but it has an inline lawnmower/motorbike style clear filter just beforehand. This isn't on the red car and definitely not OEM.

Because this "jake brake" thing is happening at the same point every time, just as the accelerator linkage hits a steeper movement on a gate lever I'm tending to think it's more to do with something inside the Solex. But I got more reading to do first.

If I can't get anywhere I'll just do the straight swap of the Holley. FWIW, I reckon the Holley's right to go. I can't test it on anything other than POVO. The other cars have too many parts missing now that kicking them over would cause auto and engine fluids of various kinds to bleed everywhere. But if you remember from before, the Holley was rekitted last year and reset to factory specs re mixtures. The car ran well at high revs but a sus head gasket and ring damage on 6th caused the lumpy idle. I would be confident that the Holley wouldn't need much tweaking, though I do need a vacuum gauge to properly tune it.

 

[Michel]

Whatteh is Jake Brake

 

[oscar]

A jake brake is an exhaust brake on trucks. I need tall dual exhausts for Povo after watching the vid below. LOL

So watch this below then the povo one again.

 

[Michel]

Thanks Simon, but I think you have fuel starvation as a problem rather than exhaust brakes...

 

[oscar]

You're right, no jake brake

Well I've narrowed the problem down and almost got it back running properly yesterday. Speaking of secondaries, the flaps above them are supposed to be closed at rest. At the beginning of Stage II those flaps or air valves remain closed for a short time. Of course a little air gets past but the vacuum created underneath sucks fuel through the bypass jets. Then as the vacuum increases and air flow increases, the air vlaves open right up exposing the Stage II jets. There's a vacuum dashpot connected to the shaft of the air valve. It's job is to make the transition further moderated by controlling how slowly the air valve opens for full throttle. So spring tension aside, without it, the air valve can open suddenly and fuel supply through jets is affected adversely.

This is pretty much what's happening with mine. The spring tension had virtually gone for the stage II air valve. Plus, the dashpot is leaking but always has. Add to that, the air valve's shaft was stiff to move. Lots of crap in the joins and bearings.

So when I go full throttle, the secondary air valve jumps open. There's no vacuum below the air valve to suck fuel through the bypass jets to begin stage II let alone fuel coming through the stage II jets. No fuel, no power.

So I should be able to retension this valve spring. Easier said then done. I can't find the sweetspot. The manual's got a plan for a custom test tool to calibrate the air valve. I can't make it. I'm also wondering whether I can get away with a dodgy dashpot. The manual refers to stage jump without it, which I don't mind, but the second stage has to be operative.


I removed the inline fuel filter thinking it might be a restriction. I couldn't find anywhere in manuals where the fuel filter is on these carby cars. There's nothing in the back like the FI cars. There's just the screen in the fuel tank and a pre filter in the Solex.

Pre filter in Solex

View of the Solex

What needs adjustment

Removing and cleaning the air valve componets made a big difference. Before it would bind when moved. It needs to be frictionless almost for an attempt at calibrating to be worthwhile.

 

[SELfor50]

Awesome dude!!! Looks like you've had a productive day on the solex.

So does this mean you've 'actually' nailed the problem??