Marlin roadster racing/sprints

[muckles.19]

Hi

Does anyone have information on suspension and other modifications for racing and speed events - not trials - for Malin Roadsters?

I can find records of 2 such cars:

PGT 949L with a Pinto - sprinting (http://www.wheelspin.info/pdf/0000/ReportFormat0.pdf)

LRO 636L with a B Series - racing and then speed events (info & attached pic from: http://www.sgtracing.co.uk/history.htm)

Best wishes
Mike

[mike.mikewood]

Re: Marlin roadster racing/sprints

Sorry, I had pasted the links badly; try these:

http://www.sgtracing.co.uk/history.htm

http://www.wheelspin.info/pdf/0000/ReportFormat0.pdf

[CosworthCabrioLee]

Re: Marlin roadster racing/sprints

Hi Mike, how far do you want to go ?? do you want to change the suspension or keep the marina set up.
On my roadster I have kept the Marina set up but modified it quite a lot.
At the rear end I have a Dolomite sprint axle located with a panard rod and top and bottom anti tramp bars, of course poly bushes and drilled and groved rear discs and calipers and Avo adjustable shocks
At the front I have Marina uprights but these have been modified to give the correct camber and caster angle by machining them, the tie bars have gone and been replaced by rose joints, Avo shock poly bushes too.it runs on 15" wheels with 185/55/ tires
I drive quite a few Marlins and this is the best handling and the only totally self centering roadster.
I notice you are not a member of the club ?? why not join there is a wealth of information out there

[mlincsmit]

Re: Marlin roadster racing/sprints

I have also modified my marina based roadster. Not quite as far as Lee, but fitted a RTL linkage at the rear end to locate the axle, better than a panhard rod, Watt's linkage is very difficult to sort with standard Marina axle - linkage is excellent and controls the car very well indeed.

I really would like more details of how Lee has altered his front axle - perhaps you could give us more details Lee, either a drawing or photos. This would help a lot of us who would like more self centering on the steering - I fitted Ford ventilated discs to the front but left the rears as drums - big improvement. Bushes and shocks all changed. Generally I now have a very well behaved car but alway room for improvement - come on Lee lets have some more info if you can please - perhaps you have already done so, and if so where.
kind regards
Mike L-S

[CosworthCabrioLee]

Re: Marlin roadster racing/sprints

Hi Mike where do I start, well the front wheels of most roadster have negative camber angle when viewed from the front and if you raise or lower the suspension the car looks awful, When we built my car with the spec it is today we tried to set the suspension up the same as my Father Lotus plus 2 as it is the same wheelbase.
The front mini wishbones were machined down on the ends and a new pivot pin made to get the correct castor angle, one day these will be replaced with tubular wishbones.
The bottom arm fixing points on the chassis were not welded to the chassis straight and in fact the passenger side front wheel was about ½” further back than the front driver side. These were both cut off and remanufactured in the correct position and welded back on, then the lower arm pivot was remanufactured so it would give the correct camber angle again following the Lotus set up.
The STD tie bars even on poly bushes make the wheel go backwards when you break hard or go fast into a corner loading it up so these have been replaced with rose joints on both ends giving proper location.
Brakes are cross drilled discs with green stuff pads again massive difference to braking performancnce
Shocks are AVO set up running stiff but not so you teeth fall out, and of course poly bushes all round, the 15” wheels made a massive difference to the road holding.
The rear of the car proved just as much head scratching.
The axle was replaced with Dolomite sprint axle as it’s the same size and pcd but much stronger, we used a panard rod to locate it but made sure that it ran along side the axle by dropping a location down from the top of the chassis, to stop axle wind up anti tramp bars were used and fixed to the top of the chassis above the springs. Again poly bushes were used all round
Avo shocks run quite stiff but I still have my teeth.
The rear disc conversion uses Citroen Xantia rear discs with VW Golf GTI callipers mounted on one off fixing points, the handbrake uses 2 cables and is similar to that of a modern car and if I want to be a hooligan then handbrake turns are not a problem. We built the conversion on a couple of spare dolomite axles I have as a test bed before transferring it to the car. All this helps as i have a very narrow tunnel to allow large seats to go in.
Like I said the car handles like no other roadster I have driven especially on twisty bumpy roads. Mike if you’re ever near me pop in for a coffee and have a go in it.

[mlincsmit]

Re: Marlin roadster racing/sprints

many thanks Lee - unless you see these things it's difficult to imagine how it's done - It realy is interesting how you have approached the whole matter of axle location etc. Were 15" wheels easy to fit, was the offset and spacers required the same as standard? Too many questions to answer here Lee, must come and have a look sometime, many thanks for your kind offer. As mentioned before I fitted the Frontline RTL linkage to the rear axle and chassis. This really has made a massive improvement to the handling of the car which had a mind of it's own before fitting.
Regards Mike L-S

[CosworthCabrioLee]

Re: Marlin roadster racing/sprints

Hi Mike, The 15" wheels came from midland wheel supplies and they supplied them with the correct offset with no spacers. will try to upload a picture of them.

[mlincsmit]

Re: Marlin roadster racing/sprints

Nice pic Lee, will have to work on my car to bring it up to the very smart condition of yours - thanks for the info - did you have to recalibrate the speedo - what tyre sizes please. I visited Midland last winter, they were very helpfull - regards Mike

[CosworthCabrioLee]

Re: Marlin roadster racing/sprints

Hi Mike, If anything then the speedo could do been recalibrated its about 10% out but as long as you are aware its not a problem, howver may do it this winter as I have a special project in mind for the dash and all the instruments will be out. What type of engine do you have in your car ??

[mlincsmit]

Re: Marlin roadster racing/sprints

Hi Lee, I used speedy cables when I re calibrated my clock, they were in London then but have i think moved over to Wales, I think -
I re engined my SWB roadster some 10 years ago or more with a Fiat 131 2L. They fit very well indeed with the appropriate mods to mounts, tunnel and prop and clutch pedel. YKC was in existance them and as always very helpful at the time. It was interesting sorting out the exhaust. Standard axle at rear with drums, front now with Ford xri disc set up with new hubs made to fit marina stud pitch - this conversion was made for me by JLH at Napton, Northants. They do a lot of mods and rebuilds for Morris Minors and Marinas when required - we had a little difficulty in sorting out the hubs but got there in the end. Ventilated and grooved and drilled discs - stops well.

I sold the car about 8 years ago (had a TVR for a while) and bought it back from the bloke late last year, he had done nothing with it, hence my rebuild over the winter. Car now runs well but will continue to modify as time goes on - hope we meet up some time - regards Mike L-S