Dollywobbler's Consolidated Tat Thread

[LightBulbFun]

On 03/03/2021 at 09:18, dollywobbler said:

Cheers LBF. It must have been sent by a HubNutter then. Which was nice of them. The wiring loom is a little short, so I couldn't entirely follow the original routing, but it still allows full travel of the handlebars, so that'll do.

BTW I was just thinking with regards to TWC improvements

I remember when you did the Good Wood trip when fitted the new pulleys you also wound the chain tensioner all the way to maximum chain tension

I wonder if it might be worth having a play with that, because if the Triplex chain is too tight then it I wonder if it might be binding on the sprockets it runs over inside the transmission and not only would that wear things out internally quicker

but I imagine would lead to unnecessary drag and as such a loss of performance

so I wonder if its worth having a play with the adjuster and seeing if you can get any improvement that way?

[dollywobbler]

It might just be me. Tricky to compare TPA on the flat with TWC on the hills. Let's just say there's some interesting video footage coming tomorrow...

[Eyersey1234]

Chodtastic news about TWC good to see she is being used. Incidentally I saw your tweet, did you get to the bottom of what the big pen that miss hu I mean the kids were on about was doing? 🤣

[LightBulbFun]

Awesome to see how well TWC is doing now! she really climbed that hill well  

will be very interesting to see how TPA and TWC compare now once the 2 are allowed to meet again!

[Zelandeth]

I reckon having watched that they're pretty similar. 

TPA isn't a huge fan of acceleration uphill, but she will hold speed pretty well.  I really do look forward to getting the opportunity to actually drive more than a junction or two down the A5...

[dollywobbler]

Oddly, TWC seems better going up really steep hills than slightly shallower ones, I think because the gearing just changes too high, so it drops her out of peak torque. She was utterly dreadful up Shelsley Walsh, even with the new pulleys and belt.

[Remspoor]

Just watched the latest video with TWC...Yes I am running late... As you approached the sea wall just looking at the size of the other cars . I know one was a Range Rover, but both made your car look way too small.

[dollywobbler]

They are tiny. This was really driven home when I was convoying with another one at various times. They are very well proportioned though, so the size doesn't stand out when you look at one in isolation. Same length as a Mini, but narrower.

[Eyersey1234]

2 hours ago, dollywobbler said:

They are tiny. This was really driven home when I was convoying with another one at various times. They are very well proportioned though, so the size doesn't stand out when you look at one in isolation. Same length as a Mini, but narrower.

I put this on @LightBulbFuns thread yesterday but will share here as well, this passed me in York yesterday 

[Talbot]

On 3/6/2021 at 12:34 PM, dollywobbler said:

pulleys

Do you still have the selection of old ones?  I'm absolutely sure that one can be modified to be adjustable so you can change the engine speed relative to the gearing on the fly.

[dollywobbler]

Yes, somewhere in my piles of tat... Can't remember which ones work a bit and which ones really don't though...

[LightBulbFun]

On 06/03/2021 at 12:34, dollywobbler said:

Oddly, TWC seems better going up really steep hills than slightly shallower ones, I think because the gearing just changes too high, so it drops her out of peak torque. She was utterly dreadful up Shelsley Walsh, even with the new pulleys and belt.

 

46 minutes ago, Talbot said:

Do you still have the selection of old ones?  I'm absolutely sure that one can be modified to be adjustable so you can change the engine speed relative to the gearing on the fly.

should in theory not be necessary since the CVT system in a Model 70 is designed to keep the engine at 3500RPM which is when the steyr puch engine develops Peak torque 

have to wonder how she would do up Shelsley walsh again now that you have sorted out her brakes etc  

and then at about 45Mph it goes into fixed ratio mode where engine speed increases with Road speed with the engine developing maximum horse power at 5000RPM which is about 70Mph or so for a Model 70

 

although I will say this is all why im really eager to see someone hook up a tachometer to a Model 70 as I am really curious to see exactly what the CVT system does IRL vs what it says it does in theory!

[dollywobbler]

True, but DAFs had a vacuum hold to access more engine power I guess - it isn't just about torque.

[Talbot]

4 hours ago, LightBulbFun said:

the CVT system in a Model 70 is designed to keep the engine at 3500RPM which is when the steyr puch engine develops Peak torque 

True, but if you could have the CVT hold the engine at 4000rpm, that's more power and would give the car better capability to climb hills.

Also... from the engine note that just about all invacars seem to produce,  that doesn't sound anything like 3500rpm to me.

[dollywobbler]

Major progress.

After pretty much a year, the offside window is back in place! I may need to revisit it, as I've only got some VERY sticky 3M tape holding it at the bottom, but it works for now and means the cabin is weatherproof again. I also gave the glass a good clean (and the filthy windscreen) and refitted the screenwash. I'd bought a pump that turned out to be far too large, so bought another one - which doesn't seem to work. So I just made the hole larger and fitted the larger pump to the windscreen. Job jobbed.

[Zelandeth]

Thanks to you having mentioned it I had a play about with Euro Truck Simulator this afternoon (the demo of it on Steam anyway).

Immediate observation: They have absolutely nailed the "ooooh, that really wide road reeeeaally doesn't feel wide any more!" feeling I remember the first time I took a coach out on a public road!  Likewise the feeling of taking your life in your hands pulling out of busy junctions.  The feeling of weight when braking downhill feels spot on too.

Completed two jobs though and didn't hit anything, so I'm counting that as a good start.  Even though I definitely need to print out a keyboard cheat sheet as there are waaaaaaay too many buttons involved to remember.  Only had one good moment of panic when I was trying to negotiate a busy junction and managed to totally lose track of which thumb stick was the steering and which was where I was looking.  Only reversed once so far but managed it!  Granted, I did line myself up beforehand to make my life easy.

[dollywobbler]

Aye. Tight spots get very tight! I've got the heavy haulage extension now, which gets very tricky. Thoroughly addicted.

Only issue I have is road closures, but the navigation system can't always find an alternative route.

 

[wuvvum]

On 3/7/2021 at 7:12 PM, Talbot said:

Also... from the engine note that just about all invacars seem to produce,  that doesn't sound anything like 3500rpm to me.

Bear in mind that it's a twin so 3,500rpm will sound like 1,750rpm on a four-pot.  Or in musical terms, the B flat two octaves below middle C.

[Cord Fourteener]

15 hours ago, wuvvum said:

Bear in mind that it's a twin so 3,500rpm will sound like 1,750rpm on a four-pot.  Or in musical terms, the B flat two octaves below middle C.

Exhaust note and music is something I've been looking into. There's a lot in this, not all of it intuitive, I've discovered. 

Anyway, assuming it's an even firing twin, as in a firing event every 360° on a four-stroke then yes it should sound half of frequency. As soon as you get into uneven firing orders, such as in V twin engines, or simply uneven length headers for the sake of packaging such as in Subaru flat 4 engines all that simple dividing by two or four goes out of the window and you start getting implied fundamentals. Like the beats you can hear when two notes that are not in tune with each other. Like the classic v8 crossplane andV-twins as well as early Subaru boxers. 

Even a standard 3 or 4 pot header has slight differences in the length of each, unless you have some mad tuned header. This means at some revs you get beats and at others you don't as the relative length of each header has a greater or lesser effect with engine speed and therefore pitch.

Anyway, apologies for the geek essay. I find it fascinating. 

[wuvvum]

It is interesting.  5-pots do it too - I can hear two separate notes when I'm revving a 5-pot, about a minor third apart.

[Cord Fourteener]

5 minutes ago, wuvvum said:

It is interesting.  5-pots do it too - I can hear two separate notes when I'm revving a 5-pot, about a minor third apart.

I'm theorising but doesn't the collector usually have the five coming together so that the middle cylinder is the shortest? Or, if the shortest exit is at one or the other end that might make it sound different again. 

Likewise on the straight 6 it is completely even firing but at high revs you can hear it burble. 

[Zelandeth]

Really interesting sounding things can happen when there has been absolutely zero attempt made at length matching at the manifold etc and the manufacturer has just let whatever happen.

Which in this case clearly sets up some sort of resonance effect at around 3000rpm.

The Invacar will have some strange header length issues as well given the branch that's tapped off the offside cylinder for manifold heating.    Plus if memory serves due to the geometry of the engine the one exhaust port is slightly further forward than the other.

The effects of all these factors is something I've always found fascinating myself.

The V12 in my Jag is very straight-six smooth at the low end, but in the middle of the rev range has an almost VR6 like warble to the exhaust note for want of a better description.

[wuvvum]

I notice you were double declutching on the down shifts - has the van got dodgy synchros or were you just doing that for the exhaust noise?

[Cord Fourteener]

12 minutes ago, wuvvum said:

I notice you were double declutching on the down shifts - has the van got dodgy synchros or were you just doing that for the exhaust noise?

I do it for fun in my synchromeshed cars. 

[Zelandeth]

14 minutes ago, wuvvum said:

I notice you were double declutching on the down shifts - has the van got dodgy synchros or were you just doing that for the exhaust noise?

It's just automatic when driving anything bigger than a car!  One of those things I found easy to learn to do, but surprisingly hard to un-learn.  Plus I figure it makes the life of the gearbox easier.

Fourth will very occasionally crunch if you really rush it, double declutching really isn't necessary though.

[dollywobbler]

Had some fun today. Video later hopefully.

Window didn't fall out, so I'm considering that a win. Longest drive I've had in TWC since 2019! Down to Saundersfoot. Very pleasant. If loud.

[LightBulbFun]

16 minutes ago, dollywobbler said:

Had some fun today. Video later hopefully.

Window didn't fall out, so I'm considering that a win. Longest drive I've had in TWC since 2019! Down to Saundersfoot. Very pleasant. If loud.

I do hope your still planning on bolting the channel to the door like Zel did, at some point soon!

I Just dont trust that tape and I dont want to see the window fly out at 60Mph! (not to mention I do believe/recall reading that the screws in the window channel help to hold the outer and inner door skins together, and with Tape you obviously dont get that same bracing effect)

(also is it me or are TWC's tyres looking a little low? tis 22 rear 17 front  yes I am that much of a sad bastard that I know the tyre pressures for a Model 70 off the top of my head LOL)

 

still very much looking forward to the video however, always enjoy seeing an Invacar/Model 70 out and about  

[dollywobbler]

The rear tyres are actually at 24psi I think, and 18 up front. Those Michelins have very soft sidewalls. 

[Zelandeth]

I don't imagine the window will go anywhere.  It's a pretty snug fit to get in, and so long as either the front or rear section is "parked" the vertical seal at either end will offer some support. 

If not wanting to go to the (not inconsiderable) faff of using nuts and bolts, even just a screw at each end would act as an anchor pretty effectively against lateral movement to offer a bit of peace of mind that you won't end up with a lap full of window one day when you close the door.

[dollywobbler]

Video here for those interested. Starts at 7pm.