History of a Lola T492 Sports 2000 chassis?

[911thillclimber]

I have an army of techies thinking this one through now.

The engine is not right still.
Had to cancell the car for Shelsley, but ran the 911 (ironically with the same type of engine as the Lola).

The carbs are now out of the question zone. My old webers are on another 911 engine and run PERFECTLY!

The one or two cylinders on the one side of the engine in trouble are always the errant ones, the other 4 are perfect and always are.

Narrows it to 2 cylinders.

Screwing the idle mixture jets in fully/dropping out does not change the engine note. Do this on the others and the engine speed drops dramatically which proves that those two are not being sparked or not getting fuel. (or both)

The old carbs are now proven to work on another 911 engine, so they were not the cause of this problem. Reasonable to presume the near new ones are ok too.

This leads to the ignition side or the state of the cylinders themselves.

The exhaust valves are correctly clear at TDC
The engine pulls strong at 6000 rpm so presumably all 6 are alive at high revs.

I hope this is just a lead/plug top cracked or similar.

Now have some extra tools in the form of lead checkers and Colour Tune (remember them?)

Will have a good go at:

Fuel delivery overall
Leads/plugs
Mixtures

I can't get to a rolling road for 2 weeks, hence the colour tune....

[haggispeed]

Very frustrating for you Graham. Presume you've done the obvious of just pulling leads off in turn ? Assuming you can on a flat 6 ? not sure of the detail layout. So the problem is at low revs but is clean at 6000, at what point does it clear up ? Have you tried changing the plugs themselves ? should be worth trying different leads, plug caps, dizzy cap etc. What's the ignition trigger, could it be something wrong with that, perhaps just try points to eliminate any electronic issues.
Yep remember Colourtune, good ol tool, still got one somewhere.

[SAMD]

Prob teaching my granny to suck eggs here, but try and test after each change so that you can find out exactly what the problem was - for future reference.

[911thillclimber]

Thanks for the thoughts!

I have tried pulling a lead in turn to see if that changed anything. It did on #4 cylinder (one of the three on the 'problem side') but then with it OFF a few bangs occured....
I deduced that i think cyliders 4 and 5 (adjacent to each other on a 911 engine, same bank on the engine) are playing up.

The interesting bit is:

When you screw the idle mixture jet in or out the engine speed does not change on cylinders 4 & 5.
Do the same on any other cylinder and the revs dip just like they should.

This means to the errant cylinders there is either no spark or no fuel.

As my old webers run perfectly on another 911 engine, and the problem is still apparent with the new carbs on there is a chance the fuelling to the carbs is at fault.
I can check the sparks with my demon Halfords spark checking caps.
I will by-pass the Filterking pressure regulator and pipe the PMO carbs direct to the red top. That should get petrol to all the chokes.

This should get me to the root:

Fuel supply
Plug leads/caps


Busy day in the garage tomorrow.

To make things worse, my 911 raced fantastically today at Barbon Manor...

[SAMD]

Originally Posted by 911thillclimber

To make things worse, my 911 raced fantastically today at Barbon Manor...

lol. be thankful for small mercies.

[911thillclimber]

Straight to the garage asap this morning. This was to be 'I fixed it' day and I was very posative after such a good day at Barbon.

I set the carbs to factory set-up (I even read the instructions)
Filled with 2 gallons of fresh fuel having checked the filters (I do listen to you all) which were clean.
I took the 3 plugs out of the offending side of the engine. #4 was 'unfired' and the other 2 sooty (as in too rich)but firing.

I had found some new plug lead from about the mid 80's with old fashined coper wires down it and an old plug connector about 1973...

Replaced the #4 existing lead and separated as much as possible the three leads.

Cranked it over forgetting to reconnect the linkage between the two carbs (idiot) so it started on one set of acellerator jets.

RAN A DREAM

Not a pop or a f@rt or a bang anywhere.

I waited for it to warm on a 1200 rpm ish tick-over (as per PMO instructions)

Not a sound. The pulses from both side are even and the heat is the same too.

After a few mins blipped the throttle and it sure does spring to life.

Stopped it and took the plugs out. All three running but #4 still not as sooty as 5 and 6 (4/5/6 are the cylinder numbers on that side of the flat 6)

Put back together and tried again.

As before, running a dream and very responsive to a 25% throttle movement blip.

Tided all the leads, made cable-tie separators for now and tried it again.

As before.

I think this is a result.

To the post mortumsee pic below)
1
Lead separated from the plug top.Plug top taken apart to find the resistor 'slug' rattling in the insulator tube.
2
Looked at the cpeer wire strands in the dist cap ferrul (?) and there i find the cable is not folded over under the copper sleeve but cut short. The ferrul/wire connection must be by the barb cutting through the insulation and into the strands.

I have always folded the wire over and then crimped the ferrul The barb sismply making sure it does not pull off later.

My replacement has the strands soldered to the ferrul for peace of mind. All the other dist ends are the same as this one, so the lot will be changed to the fold and solder method.

So there we are job done at last.

It was always going to be something daft or catastrophic.

Prepping the car now for a weekend at Loton next week.





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[SAMD]

Good good. Happy bunny's all round then!

[911thillclimber]

Yep, and about time too!

Getting ready for Loton Park hillclimb this weekend.

I still have a short list of things to do before the car is almost as i want it.

Loton is my Clubs own track and i know it really well so confident about the place.

I now need to get my head around learning to drive it.

Not so easy as bits of metal.

[haggispeed]

so pleased you have found the source of the problems Graham, it's always the little things isn't it. Now you've become such and expert at carbs can you tell me why my FF engine in the Clubmans car hesitates and misses evertime I exit a hard right hander, I'm thinking float levels but have checked and they're OK, no holes in the floats, plenty of fuel in tank.
Have a great time at Loton.

[911thillclimber]

Me an expert on ANYTHING? Wrong Hillclimber I think....
Sounds like you need some foam in the tank to stop it sloshing around on the curves?

Had an email off the very much missed Driftwood today (he is over on Facebook now).

He spoke to Vic Lee about the car. VL had the car for some tweeks after Alan Humberstone ran it at Brands after Tony and John had rebuilt the car into the chassis plate less tub.

Vic actually remembers the car that came to him less body to Rob Mason's garage in 87/88 (who is Rob Mason?)
The garage was cleared of all effects though and VL cannot recall the palte missing/coming off.
He still sees Rob's daughter so will ask if Rob kept any pics of the car. If this happens it just might rattle a few braincells?

I think the hunt for the chassis number will remain un-solved for some time to come.
Might be time to open the subject up on some other web sites just in case.....

[haggispeed]

exspurt - "has been" under pressure....
yes, foam in the (petrol) tank, not the oil tank thank goodness
Had the same mail, "who is Rob Mason ?" one of the great special saloon drivers of the 80's, (have a look at the special saloon thread on here.) Strange it should have gone to Rob sans bodywork ? especially so soon after it was finished.
I wonder if the chassis plate was used to "ring" another car ?

[911thillclimber]

That is my fear in which case I'm doomed as nobody will surrender the plate to me and I can't prove a thing. That's assuming they know anyway after all these years and change of ownership.

I wonder how the car got to Brian at Autoquip?(presumeably from Rob's place or Alan H direct??)

[haggispeed]

ah well - another gap in the history for you to figure out....

[911thillclimber]

Yes, it is all a bit like crazy paving and trying to make sense of the irregular bits into a neat square!

Back in the middle of this life-line there is the replacement T492 from a guy in Herne Bay in 1987 with an orange body.
Your pics show the chassis plate in place.
The life of the poor car is like a soap opera after that living in the shaddows of a difficult era until it emerges to Mike's hands from Brian at Autoquip.

Someone picked up a drill with a 3mm drill bit and drilled those 2 rivits out.

The plate was on the tub from 1978 to about 1988 and yet there is no sign of corrosion, no sign of polish marks around the area of the plate on the tub sheet alloy.

It is as if there never was one there! Bizzare.

[ASDS]

Originally Posted by 911thillclimber

Someone picked up a drill with a 3mm drill bit and drilled those 2 rivits out.

Can you be sure? I have talked to several people and there has been a tendency for the rivets to fracture or the plate crack with vibration. The plate then falls down into the cockpit and gets thrown out with all the other detritus that collects in the car.

[911thillclimber]

It has to be said that the area where the chassis plate was (and there was one, as in Tony's pics of the tub he sent me) is unmarked. Almost tempting to think there never was one!

Just seems an odd thing to do unless you wanted to re-locate it. I have seen an early T490 with the plate in a totally different place to the norm. The original front roll cages had the chassis numbers repeated as stamped numbers, but my car lost it's cage when it went 'Karmann Ghia'!

Everything is against me finding the true ID of the Orange bodied doner car.

[SAMD]

Are the holes for the rivets the correct size? If they are you are no better off, but if they were a fraction bigger (or one of them is a fraction bigger) then it is likely they were drilled out and you could discount the previous theory. Although I think there would be visible signs if the previous theory was correct, ie; it would be very unlikely for both rivets to break at the same time so when one rivet disappeared as the plate would loosen the 'swivel' marks would be left on the alloy.

[911thillclimber]

I simply think the plate was removed by someone in the late 80's/90's and off it went to another car.

Maybe there is another T 492 buzzing round the tracks with a new tub and the chassis plate attached.

I just would like to close the loop, find the chassis number and call it a day! Sadly, these kind of things bug me.

Even if i found the man from Herne Bay who had my car then I doubt he would recall the chassis number?(unless you have a memory like Driftwoods!)

Fingers crossed all is well at Loton this weekend.
The car needs to pay me back now.

[haggispeed]

Hope Loton goes well and the rain holds off !!

[911thillclimber]

Dropped the car off there this afternoon, almost literally as it rolled forwards on the trailer when unleashed nearly crunching the front...

The sky is very grey, but the forecast is good for Sat, not so good for sunday.

I hope it runs on all 6 with no bangs or f#rts, it passes the 2/3's Red line noise test, and i can get 3 gears + reverse!

Race report on Sat/Sun.

nearly 41,000 hits, good grief!

Hope I don't dissapoint.

www.hdlcc.com

Same meeting last year, very first time out.
I'm older and wiser because of this thing!

[haggispeed]

nearly 41,000 hits, good grief!

I'm older and wiser because of this thing!

and Faster too I hope !!!!

I see you even get a mention on thier web site
Complex paddock plan, everyone gets an assigned parking spot then ?

[911thillclimber]

I am an ex-President, current Committee member and Mrs Hillclimber and I do the Newsletter!
Oh, and I'm in charge of the signs on the track too....

Such a social life!

The car I'm sure will be fast once I get into the ways for the gear change and the grip.
I've been on slicks before in my Impreza for 3 years and they are great, but never this grip in such a light car.

240 bhp by now on these carbs, maybe more and 220 lbft from 2500rpm to 6K, so about 460 bhp/ton.
The Impreza was 340 bhp in 1.25 tons, but 4x4.(300 bhp/ton)
My 911 220bhp/1000Kg, so 220bhp/ton

The top runners in hillclimbs are about 800/1000 bhp/ton.

You should come and see the game.

Paddock is pre-assigned and cramped but at least I'm on tarmac this time.

Lots to learn here!

[911thillclimber]

Really not sure how to see today.

The first run was in the chill of the morning, but engine started and ran quietly.
Got to the Noise test and passed..! just 101 dB. Good start.
Ran up the hill carefully and took 2 to 3 but ended up sweetly in 5th to trundle up the hill rather slowly. But everything seemed to work except my right hand.

Second run was the same start but got 3rd cleanly and the car sure does go in second. On the return down the hill though....

Yep, the pops and bangs are back.
I am flabbergasted, especially as they were occuring randomly on the OTHER side of the engine, not the side it has always been on.

Took the plugs out and the new offending side sure is running WEAK.

The third practice run went well, a full 8 seconds off the first run. Found third ok on several occations, but the bangs are still there.
Brakes are good and i need to get 'into' them, and i had a good start, 2.19 secs from standing to the 64 foot marker (do this dash in 2 secs and you have pulled 1 g)

As you can gather I'm trying to find posatives to the day!

Will run tomorrow as we are, and fit all new leads and maybe plug tops too to all 6 cylinders. It then needs sorting/balancing on the rollers.

Maybe 10 steps forwards, 2 steps back? (or 10 -4?)

I don't know anymore.

[911thillclimber]

Put 6 new leads on the car this morning, and the pops and bangs were still there in full voice. Nuts.

First run up the hill was quite good, even I was enjoying the fresh air open top car.
Popped and banged on tick-over but ran strong and true up the hill, a little bit faster. The car certainly accellerates. Pity the gear change is not so hot.
Deceided to ignor the pops. With the car noise measured at 101 dB sod it!

Tweeked the dampers 3 clicks front and back from fully soft for the second run and put the body back on.
Lunchtime was spent talking to a lot of people about the car, so went to the second timed run relaxed.

The bloody thing ran SILENTLY! Not a pop or a squeek any where, any time. And I'd done nothing to it!?

Went up the hill in 62 seconds which is quite pathetic, but at least I'm getting on with it.
This car is not easy to drive yet.

A few pics for those watching:

Class mates:



It gets busy getting through here fast:

[911thillclimber]

http://www.youtube.com/watch?v=RbUqjE1cv_k