Back at last after nearly two years

[ukkid35]

I have a working car again

Last time I was able to drive it was August 2017, because shortly afterwards I discovered head gasket failure again

The cause was not what you'd expect, but that didn't matter because when I removed the heads I found one of the valve guides was lose in the head

I decided it was time to completely rebuild the heads, as my machinist condemned the exhaust valves, so I replaced all valves and springs, and shimmed the springs to spec, after the machinist replaced the exhaust guides and re-cut the seats

Then when I eventually got it back together in October last year I had an issue with a valve shim that tried to escape, and the heads still weren't sealing

But now it all seems to be working properly

The two traces are from my original trip to Chesterfield six years ago, and from Saturday

The gains are really impressive, even if the headline figure has only risen 6bhp

More importantly the pinking which probably caused the valve guide failure has now finally been banished (unless the engine overheats)

This is probably mainly due to neutral valve timing as recommended by Joolz, rather than using the factory 1.5mm advance

I've also got to the bottom of a weird issue where the engine would refuse to rev over 2k under load, making it very difficult even to limp home - it is an ECU heat soak issue, proved by swapping it out with a spare (and back again to be sure)

At last, I get my evenings and weekends back, as I won't have to be under the car, or in the engine bay

[Jhonno]

Nice one Paul!

[morebeanz]

Interesting comment about the ECU heat sink issue, as I have had this on the odd occasion when things have got very hot in summer or standing traffic.

Is there a nifty cure? Or is it a full ECU replacement job?

[ukkid35]

morebeanz said:

Interesting comment about the ECU heat sink issue, as I have had this on the odd occasion when things have got very hot in summer or standing traffic.

Is there a nifty cure? Or is it a full ECU replacement job?

I don't know, and I don't know whether the spare will suffer from the same issue

Fortunately a swap is not too arduous, but it would be really nice to know what the underlying cause is and whether it can be fixed

I have actually bought a 30mm fan, with the intention of drilling some holes in the lid and then using the fan to draw air from one side of the large heatsink to the other, but I haven't actually done so yet

[morebeanz]

Yes, I was thinking that maybe a small pc fan or equivalent might do something useful too. I wonder how often it makes a difference in the real world, ie I wonder whether it actually impedes performance to a small/tiny degree at all times?

[spitfire4v8]

I forgot to mention when you were in paul .. Jody at Python Racing is very clued up on the electronics side of things .. if your car is ok running on your spare ecu you might want to pop the faulty one in the post or take it to him, explain what's going on, and see if he can pinpoint the source of the issue.

Some of the components are obsolete for the earlier ecus though, so if it's one of those components, and jody can't source a suitable alternative, then it's probably going to be u/s for good for that ecu

[ukkid35]

I was thinking it would probably be worth replacing the handful of electrolytics that are on the board with the highest quality replacements I can find

Nothing to lose, and it might even help

I might even replace the battery backup memory modules too (not that they could be causing this particular issue)

I'm definitely going to make sure that I always carry a spare in the car from now on

[ukkid35]

ukkid35 said:

At last, I get my evenings and weekends back, as I won't have to be under the car, or in the engine bay

Who was I kidding?

I spent all last night changing a burnt out lambda, and trying to work out how to fix a molten reverse light switch connector

There is so little access, and I have no intention of removing the exhaust manifold to fix it

Still left to do - replace oil bypass valve spring, raise rear ride height slightly

Then head off to Germany on Friday night, perhaps stopping by the Spa Classic on the way

[Chimp871]

Well done... 2 years is a long time to keep working at repairs and still be motivated.

Curious to see how your 'chips' get on.

[CerbWill]

Excellent news Paul!

[Byker28i]

ukkid35 said:

Then head off to Germany on Friday night, perhaps stopping by the Spa Classic on the way

Pop in - I'll be there

[Mr Cerbera]

ukkid35 said:

At last, I get my evenings and weekends back, as I won't have to be under the car, or in the engine bay

You'll be bored to death in no time

Don't forget Luxy lies a very nice dog-leg between Spa & The Ring

[TwinKam]

Have a great trip, Paul, drive safely now!
Rik

[Cyclone1]

Well done getting it back on the road and the figures look great.

[ukkid35]

Cyclone1 said:

Well done getting it back on the road and the figures look great.

Thanks - I'm pleased with the figures, but the real result is that it is so driveable now

I can actually use the rev range 900 - 2200, with throttle, never been able to do that before

That fact that it is quicker than it's ever been, with so much more mid range torque, is a very nice benefit - but you have to exercise a degree of caution because it can all get out of hand very quickly

[Classic Chim]

ukkid35 said:

Thanks - I'm pleased with the figures, but the real result is that it is so driveable now

I can actually use the rev range 900 - 2200, with throttle, never been able to do that before

That fact that it is quicker than it's ever been, with so much more mid range torque, is a very nice benefit - but you have to exercise a degree of caution because it can all get out of hand very quickly

That last paragraph cracked me up, such an understated way of putting loosing it big time

It’s very easy to do for sure.

I never realised the later cars struggled at low revs but it’s a race engine after all I suppose.

Nice power there, must feel dramatic and vet exciting. N/a forever in my book

[ukkid35]

Not a quick time, but it's always fun taking another TVR owner for a PAX lap

My excuse is that it's effectively the first time I've driven the car in nearly two years

Unfortunately I've lost my GoPro2 and this was also the first time I'd used a GoPro5 which a friend generously lent to me

I should have switched off the image stabilisation, and the sound is pretty weird too, oh well...

https://youtu.be/x3Y1F1LwMB4

[Chimp871]

Nice.

How come the barrier was open?

[ukkid35]

Chimp871 said:

Nice.

How come the barrier was open?

Dottinger Hohe is open, so you can Vmax the car if you want

In fact I'm looking forward to doing this next month now that the engine is working properly again

https://vimeo.com/217287939

In that clip you can see a much better line through the final corner before the straight

My line through Galgenkopf (10:21) was just one of several errors that I called out on the full lap video

I was also too wide on Miss Hit Miss (5:27), and my entry in to Hohe Acht (8:08) was horrible

I am also incredibly conservative, braking much earlier than most, because I really like driving home afterwards

Edited by ukkid35 on Wednesday 12th June 18:46

[Penelope Stopit]

ukkid35 said:

Not a quick time, but it's always fun taking another TVR owner for a PAX lap

My excuse is that it's effectively the first time I've driven the car in nearly two years

Unfortunately I've lost my GoPro2 and this was also the first time I'd used a GoPro5 which a friend generously lent to me

I should have switched off the image stabilisation, and the sound is pretty weird too, oh well...

https://youtu.be/x3Y1F1LwMB4

Great video, nice driving