The Lotus Grand Tourers

it happened at last, an engine breakdown first time the excel has failed. on Saturday after sitting in sweltering temperatures in the huge queue on the a43 to get into Silverstone I was fed up and decided to go towcester for refreshments as I pulled out of the line the car stuttered but then continued. no unusual noises or other smyptons until my wife noticed a cloud of smoke exiting the left of the bonnet. stopped and noticed that the engine was making a loud clicking, valve gear. we and the car were recovered to lotus bits by mike and nephew. mike reckoned that the heat had caused a valve to stick breaking the cam follower whose bits then punched an hole in the cam carrier. bad news, complete rebuild needed, good news, a chance to fit some rather good bits in the engine. I cannot praise the service given by mike enough.
I shall never visit the classic on a Saturday again.
I cannot help but wonder if it was the acceleration out of the queue that caused it, I suppose that if there is a lesson it is to be very gentle with the loud pedal in traffic jams even if the temp guage shows that things are under control.

on Friday I was queuing in MacDonald's drive thru and noticed my temps creeping up to 90 at which point I normally would here "tick,tick,tick" and my fans kick-in. however with 2 young kids in back seats making their usual amount of noise I didn't hear anything but noticed my temps continue to rise to 100 at which point I turned engine off.

Anyway I traced the issue to the fan relay, quite convenient that the relay next to it which works the heater fans can also work one rad fan. so I swapped them over until my new relay comes

point of my post is , its sods law you get an cooling issue on one of the hottest days of year whilst stuck in a jam

That is really bad luck Alan, hope the top end strip down doesn't turn up anything else.
The rest of us met up in the Club Lotus area for an introductory chat. I had a great day despite the high temps.
The trick to escaping the queue is to arrive at 08.00hrs or soon thereafter and drive straight in.

at Silverstone, despite the heat and queue every thing appeared to be working and the engine kept its cool so it was my driving as I pulled out of the queue or bad luck that caused the valve to stick. however every cloud has a silver lining. My dear wife has agreed to an engine rebuild, but what a rebuild, lotus bits 2.5 litre with steel bottom end and cnc head but detuned by retaining carbs and standard cams, mike reckons substantial power increase but more important to me will be the increase in torque. someone once said that torque wins races power wins boasting right in the pub. the cost is substantial, and a commercial secret, but should make the car into what lotus should have made. most important if I become more power hungry it can be upgraded later with the engine in situ and at relatively little cost. can't wait to collect the car some eight weeks or more down the line.

got he mike's estimares of power output this morning, 220 approx bhp but much more important 220lbft torque, superb, exactly what I always wanted. this is going to be a step to excel perfection and still within the bounds of originality. this car will never be for sale.

RE: - the blowup from standstill in traffic to quick acceleration.
Chatting with Gerald Turner a while back, he said this was a common problem with the 912 engine when they were always sat in traffic due to the oil pressures going dangerously low... i.e heat build up, pressure dropping, low revs and then a sudden demand for lubrication.
Part of the reason my oil cooler has been moved in front of the radiator instead of behind it and in the hot engine bay is as a result of the above conversation.
In traffic - I used to see a drop of 0.5 - 1 bar pressure difference between hot oil and REALLY hot oil in traffic.

You may want to think about a similar solution.

BTW:- You have created yourself a small nightmare now with the extra power.
Brakes will melt and give up horribly when you need them most
The power will need more careful control from the diff (curse that diff as you walk out of the hedge)
Hope your suspension is good...etc.....

Good luck.... I bet you a tenner, you end up going all out as a result. When you improve one area, you see the failing parts elsewhere.
I accept cash, cheque and paypal

fueltheburn wrote: You may want to think about a similar solution.

BTW:- You have created yourself a small nightmare now with the extra power.
Brakes will melt and give up horribly when you need them most
The power will need more careful control from the diff (curse that diff as you walk out of the hedge)
Hope your suspension is good...etc.....

Good luck.... I bet you a tenner, you end up going all out as a result. When you improve one area, you see the failing parts elsewhere.
I accept cash, cheque and paypal

I would agree with "K" with regards to the brakes the ability to not be there after some pushing on and at the very least either needs to be considered. With regards to the diff I would love an LSD but to be honest the chassis is so good on the excel that a standard one really will get u out of trouble either by backing off or pushing through and as long as you are aware you will be ok.

thank you both for the advice, I doubt that by the time I get the car back it will do much more than drive home until next year, especially since all my petrol money is now going towards lotus bits goodies, by next spring I will have recovered from the financial shock sufficiently to upgrade the brakes. until then I shall be content to feel my way and to restrict use of the power to acceleration on straight roads rather than spirited driving on twisty roads.
k, was that bet that I would go the whole way on the remaining upgrades, cams etc or that I would use all the power that the upgrade has given me before improving the brakes, suspension already done by the way.

alanbell wrote:My dear wife has agreed to an engine rebuild, .

I need a new wife

Hawaiis0 wrote:

alanbell wrote:My dear wife has agreed to an engine rebuild, .

I need a new wife

I haven't got a wife... obvious really

alanbell wrote:thank you both for the advice, I doubt that by the time I get the car back it will do much more than drive home until next year, especially since all my petrol money is now going towards lotus bits goodies, by next spring I will have recovered from the financial shock sufficiently to upgrade the brakes. until then I shall be content to feel my way and to restrict use of the power to acceleration on straight roads rather than spirited driving on twisty roads.
k, was that bet that I would go the whole way on the remaining upgrades, cams etc or that I would use all the power that the upgrade has given me before improving the brakes, suspension already done by the way.

BALDERDASH dear fellow. The moment you know the engine is nicely run in... demon lead foot will take over... if it doesn't - DONT buy a bigger engine with more power
Having been out in a car with 6 pots up front it seriously shows how woefully inadequate the originals are.

The bet is that once you start using the engine properly you will notice where your car is lacking in control to handle the extra power. It will frustrate you and you will have to do something about it.


The last big change for me is a wider foot print on the tyres