Winter Projects

[SAMD]

Originally Posted by terence bower

I worked on a few of those whilst serving my apprentiship in London Mike,we sometimes just finished them off.

I used to finish minis off too, Usually around our back roads

[terence]

Insurance job's ?
I meant in order for them to be sold Sam,not 'torch em!

[andy97]

Double post, sorry

[andy97]

Porsche 924 Engine Mods

We talked earlier in this thread about the use of 924s for the 360 6 hour race. Some are clearly being prepped for the race from scratch & others may be sourced from the existing 924 series but it is clear that the 924 engine is not too capable of much outright power. That's OK in a one make series or for the 360 where reliability is more important but one or two people may want to investigate a few more ponies.

This comes from the 924 series web site, where it has been suggested that a 924 Turbo head on the n/a block may help the engine breath better:

"The head on the 924 is extremely restrictive and that is where the problem lies. The turbo head has a combustion chamber whereas the normally aspirated head doesnt. Both pistons have combustion chambers, the turbo head has the combustion chamber to lower the compression ratio. The theory goes that you can use Golf pistons and rods which utilise a flat (ish) topped piston with the turbo head. There is nothing to stop you using carburettors, or for example a megasquirt with this - but the head is still the weak point, especially the hump in the intake port where the water jacket runs.

Achillies heel two is the valve seats, which are shrunk into the head. Larger ones would be required for bigger valves to be fitted. The valves aren't bad but are very thick and carry lots of weight as well as having a thick stem. Added to this, the valve guides are of good material, but impinge on the inlet port. New bullet nose guides would probably provide a useful increase in flow. If you add a decent bottom end, with everything lightened, and dry sump it, you would end up with a half decent 924 engine - but - again - in comparison to other 2 litre engines, you may struggle for outright horsepower.

The standard exhaust manifold is very heavy and doesn't flow - best weighed in for scrap! I have no proof, but I suspect a good tubular 4 into 2 into 1 would prove beneficial. However, Ford engines of the same heron head type can work well with a 4 into 1. 4,2,1 for torque, 4 to 1 for outright power".

Might just be easier to stick with the 924 series Piper cam & live without the hassle & expense, though, I suppose!

[Mike Bell]

Originally Posted by andy97

Porsche 924 Engine Mods


The standard exhaust manifold is very heavy and doesn't flow - best weighed in for scrap! I have no proof, but I suspect a good tubular 4 into 2 into 1 would prove beneficial. However, Ford engines of the same heron head type can work well with a 4 into 1. 4,2,1 for torque, 4 to 1 for outright power".

Might just be easier to stick with the 924 series Piper cam & live without the hassle & expense, though, I suppose!

Andy, you could certainly save more than a few kgs ditching the exhaust manifold but as yet havn't seen anyone making a tubular one! Probably no demand?

There are more subtle mods to the 924 series engines (as am finding out) than just cam and pulley, but at the end of the day am sticking to what have got and try and make it ultra reliable.........

[Mike Bell]

Update on the 6hr 924 progress. The original idea with this car was to run it as it was, but by the time I have finished the only subassembly of it not removed and rebuilt will be the rear suspension. Found today that in order to get full throttle previously a cable tie was put round the bulkhead end of outer cable where it went through to take up slack. Now has better bracket other end that allows more adjustment and no cable tie...

Now waiting for local sparkies to finish rebuilding alternators (spare as well) and then can modify mounting arrangement to get balance hopefully between absorbing vibration and flapping about enough to throw belt off! Sadly will still be 'underneath' and close to exhaust manifold but can't do much about that. I see 924 Turbo has Alt mounted high but inlet arrangement allows room that n/a model doesn't! All new wiring works as intended so looking forward to being able to put some fuel and oil in and firing it up

[zefarelly]

Originally Posted by Mike Bell

There are more subtle mods to the 924 series engines (as am finding out) than just cam and pulley, but at the end of the day am sticking to what have got and try and make it ultra reliable.........

what, take it out and a put a crossflow in?

[Mike Bell]

Originally Posted by zefarelly

what, take it out and a put a crossflow in?

At least I would have a fair idea of how it works

[zefarelly]

quite, from the Haynes crossflow engine book

'if its jangly, its properly run in, thrash it hard, if it rattles, carry on, it'll do another 20 000 miles . . . . if its really clanky, just accelerate a little slower until you get to 5000rpm, it'll be fine for another 20 000 miles.

if its really quiet and smooth, expect something major to happen any second!!!

[grantp]

Originally Posted by Mike Bell

Update on the 6hr 924 progress. The original idea with this car was to run it as it was, but by the time I have finished the only subassembly of it not removed and rebuilt will be the rear suspension.

Mike,

I can't find it again now - picture size is a bit demanding in my old eyes - but I thought I saw a bolt head - or perhaps a nut - that you had only half polished.

If I spot it again I'll make a note of it ....

".... to run it as it was ...."

Yeah, right.

[Mike Bell]

Originally Posted by grantp

Mike,

I can't find it again now - picture size is a bit demanding in my old eyes - but I thought I saw a bolt head - or perhaps a nut - that you had only half polished.

If I spot it again I'll make a note of it ....

".... to run it as it was ...."

Yeah, right.

It ain't that pretty when you get close, but considering had been standing outside a while before I bought it has cleaned up OK.

The pics are small on purpose so's not to give too many secrets away to all the other 924 builders

[midgetman]

Hey Mike don't worry Ive had a couple of beers and can't see that straight anyway. Is that a bottle of Tango?

[Mike Bell]

Originally Posted by midgetman

Hey Mike don't worry Ive had a couple of beers and can't see that straight anyway. Is that a bottle of Tango?

Don't blame ipad for spelling mistakes, blame the beer........

Car is more than a bit orange but camera flash seems to make it worse! Have a plan to tone bodywork down a bit when done. (Will also hide some of the ripples and scuffs )

Don't know what goes on in that Porsche championship but have seen rally cars with less floor pan damage

[andy97]

Its a real pity that Porsche chose to base the engine for the 924 on the LT Van engine rather than taking the engine from the Golf GTi. Oh well, too late now!

[Mike Bell]

Originally Posted by andy97

Its a real pity that Porsche chose to base the engine for the 924 on the LT Van engine rather than taking the engine from the Golf GTi. Oh well, too late now!

Although they would probably say it came from the Audi 100

The Le Mans 924 Carrera GTS / GTR things produced well over 300bhp and lasted the 24 hours so it is possible to get the engine to deliver the goods- at a price!

[Lancsbreaker]

My stepson ran in the Hankook 924 challenge way back in the mid-90s - it was supposed to be a "budget" series, and as he was a junior lieutenant in the Army at the time his disposable income wasn't that great, so we approached it in that light.....when he ran a big-end bearing in practice at the away round at Zolder, I sourced a replacement engine from one of my fellow scrappies from a wrecked 924 and dropped it in as was, got him out for the next round at Donington IIRC - when chatting about what we'd done, one of the more "precious" racers rather sniffily remarked that if he'd had to do that he just wouldn't contemplate racing.......he didn't seem too impressed when I told him that it seemed good enough to me for the LT Van coupe challenge..... - and that I'd sourced another spare now from an LT - did it matter if it was a diesel?

[Al Weyman]

Originally Posted by andy97

Its a real pity that Porsche chose to base the engine for the 924 on the LT Van engine rather than taking the engine from the Golf GTi. Oh well, too late now!

Its a pity Leyland decided to develop a pig v8 from a Dolomite engine instead of using the already in production Rover V8, they do some strange things car manufacturers!

[Peter Mallett]

Originally Posted by Al Weyman

Its a pity Leyland decided to develop a pig v8 from a Dolomite engine instead of using the already in production Rover V8, they do some strange things car manufacturers!

That one did strange things as a hobby.

[Al Weyman]

Didnt they just, what a superb car the Stag would have been if originally fitted with the Rover Buick engine.

[delta]

Getting ahead of myself but driving back from workshop this morning in the snow and i was off day dreaming that may be i could turn the Escort into a rally car for some Historic events in the winter.WDYT.

[midgetman]

The reason Kerbside Racing hasn't confirmed its entry in to the 6 hours yet:

[Al Weyman]

I nearly bought one brand newly converted Mk1 a few months ago that was turn key ready to rally with mostley all new components but as thats not what I am into I never bothered in the end. It was under 5k though and would have cost well in excess of double maybe treble to prepared it to the standard, I am sorry in a way I never went ahead although I did leave an offer he never got back.

Blimey Max dont you have a workshop, I used to work like that till I moved here and custom built a big un! Thinking of converting into a bunglow and cutting and running now though!

[Mike Bell]

Originally Posted by delta

Getting ahead of myself but driving back from workshop this morning in the snow and i was off day dreaming that may be i could turn the Escort into a rally car for some Historic events in the winter.WDYT.

Better start again with the shell preparation then

[Mike Bell]

Originally Posted by midgetman

The reason Kerbside Racing hasn't confirmed its entry in to the 6 hours yet:

Was -11 ouside this morning here and just a few degrees warmer in workshop, but at least no snow (inside)! Took double time expected to fit exhaust manifold because everything so cold to handle....

Going to play with seat brackets this afternoon as don't have to lie on floor to do that!

[GORDON STREETER]

Well I failed to get up the drive this morning so there's not a lot of hope of getting to Spain for Christmas !