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I originally had long turbo shaft and short turbo shaft . after a problem with the longer shaft popping out I changed to diesel long shaft. the car was ok until I drove it round a track which broke the cage on the outer cv of the short shaft. the current setup is back to original turbo long driveshaft having moved the engine as far right as it will go. it has not been tested on a track yet but so far so good.
Yes, I think thats it John.
WHY hasn't Mark/Marlin said this???
I get quite wound up by several issues that have popped up. It's like the R+D is done by customers, not by Marlin!!!
Sounds familiar - building a K20A2 engined car is taking me ages, as I'm doing a number of things myself (3 of the 4 engine mounts for starters). So far the only thing that has fitted in the engine bay is the offside engine mount, all the other engine bay components don't fit / work. Not a problem as such, as I'm enjoying the project, but it's certainly going to take me longer than I first envisaged.
Oh, just to keep things on topic, sorting driveshafts for the type-r version hasn't been a smooth process. Mine have just gone back to the manufacturer, as they are wrong on a number of counts.
So are you running with both short and long driveshaft from turbo?
Not sure if there's a difference but you used a 800 donor where as John/Trev used a 400 and I and some others used a 200. Might mean diffferent driveshaft lengths.
Thought I was sorted, had the car on the road for a month and everything was going so well.....................
Then One surprise follows another, on the 18th August I celebrated my second heart attack, thanks to the skills of Dr Julian Strange I survived.
A day later and my son thought it was safe to push the pedal to the metal bang another short driveshaft bites the dust, mind you at least this time it did not puncture nice ventilation holes in the gearbox.
So now I'm in the market for a new 'short' shaft.
Can I just add a thanks for the earlier notes regarding new mounts, I'll send an email to Terry.
I'm finding the 200 bhp real fun, but interested in what increases are available, possible head mods and piston changes?
So are you running with both short and long driveshaft from turbo?
Not sure if there's a difference but you used a 800 donor where as John/Trev used a 400 and I and some others used a 200. Might mean diffferent driveshaft lengths.
I am currently running 200 turbo long and short shaft. I have driven car quite hard without any problems!!!! The only niggle is a slight vibration under accelleration between 20-30 mph. I am sure this is down to the tight angle of the short shaft. I have added an additional stabiliser to gearbox and also a tension cable laterally from chassis to engine like i saw on Marks demo turbo.
and just to add even more heartache i went out today and one of the driveshafts sounds as tho its knackered....so thats 150 miles and dead driveshaft.........not happy.
Sorry to hear about the recent failures - I heard the Rover 200 Coupe race cars had shaft difficulties, but I thought the Marlin being that much lighter might be a bit softer on the shafts........ although the angle can't help.
Are all turbo builders experiencing failure at the gearbox end, or are there instances of the outer CV packing up as a result of the input angle?
Yes it is odd how the shaft always pulls out at the 'box' end. Jon (Limpabit has just pulled his long driveshaft for the first time. He and I recently spent an hour or two discussing the options. I really do not mind lashing out on these items, since starting my build I guess I have spent around £500. But enough is enough and now I want one that is going to do the job permanently.
As far as it goes, a friend has added 20mm on to my short driveshaft, the join looks good but we'll have to see what happens when it tries to handle the power. The good news is if it works we will at last have a difinitive answer to the problem.
If this shaft does not pull out, I intend to ask one of the specialist manufacturers to make one of this size.
I've been scratching heads with Trev and John (Marlin Turbo).
There's 1 difference between mine and Trev's. I have tilted my engine (found out the MGf also has it's engine tilted). It might mean different configurations for dfferenyt builders. John (Marlin turbo) said Turbo long shaft and diesel short shaft. But as mine has pulled, it looks like I will need the diesel lomg shaft (as this is a bit longer) for my configuration. Can't tell about the short one as Trev said (not sure which one John's got problems with) as this happens when turning left only. But as it stands, the longer of the two shorter ones, Trev's got problems with.
So as Trev's getting his extended, does the 600 or 800 have longer short driveshafts than the 200/400 models?
If you read all the posts on driveshafts it changes direction constantly on the best setup.
I understood that the turbo model used 220 driveshafts, turbo or normally aspirated are the same I think.
I had a problem in the early stages of the long shaft popping out of the inner joint, the cure was thought to be to fit a longer shaft (diesel). This cured the popping out but the real problem was I needed to move the engine further to the right. I only found this problem out after breaking the left hand cv outer cage during hard cornering. The problem is if you fit the longer diesel shaft on the right it tightens the angle of the left hand shaft which is already at it's limit. If it requires modifying engine mounts to move engine across further then do it. I have about 10mm clearance between timing cover and chassis rail and I might even try and reduce this even further.
I also have a stabiliser rod from gearbox to chassis to prevent engine rotating too much and straining the shafts even more.
I still have a problem in that an annoying vibration at 25-35mph under load, I am sure this is due to the angle of the short driveshaft but I'm not certain. I think getting the engine location right for the driveshafts is paramount and would advise all builders to make sure that they use the maximum space available to have the engine as far to the right as possible.
Exactly as you describe is I think what has happen to Trev. Has diesel long shaft and broke the shorter petrol shaft during cornering.
My shaft has popped using turbo long shaft.
Just taken some measurements. I have 27mm between timing cover and chassis rail. But to move it to 10mm will not happen. I have only 11mm between chassis and alternator pulley wheel. Maybe the alternator is the difference between the 200 and 800? How much clearance have you got at the alternator Brian?
I have made my own alternator mounting bracket fitted in a different position due to not fitting standard water pump. It fortunately clears chassis rails comfortably.
I have used 214 alternator for cheapness and with standard v belt.
I know Marlin used original configeration on the turbo demonstrater so you would assume it should work!!.
Well I have extended my broken short driveshaft by 20 mm and the fit now appears to be correct, problem is I do not trust the welding and as the first driveshaft 'pulling' created a number of air vents in the gearbox so that needed replacement too, I am loathe to test this particular shaft.
I have therefore decided to purchase a one off from a manufacturer, with aan overall compressed length of 605 mm. So far I have had a quote of £230.00 plus vat and delivery, so nigh on £280.00.
While I am prepared to pay this sum to correct the problem once and for all, I can't help but feel it's a little steep price wise.
Does any builder know of a manufacturer who may be a little more realistic in their pricing? Then again perhaps it's me who's being unreasonable.
Had a look at Andy's car last weekend. Cheers Andy. And had a spin in it. WOW!
But see how the engine bits are done. I think I see the new engine mounts as well.
The timing belt side of engine is using near standard mounting with a weilded plate for the dog bone. But is mount on the rear most slot on the chassis. The gearbox end is attached to the chassis where I think the K series is attached to. The circular bits. The result is the short driveshaft is great, not perfect but works. Has a very slight bend. The engine is located at a slight angle with the timing side of the engine more towards the front of the car than the gearbox end.
Many thanks for Andy for a great time not only in the car, but for me saving so much time and trouble for seeing how his has been done.
So asked Marlin for some updated engine mounts.
Also Andy has used diesel driveshafts for both sides.
