BMW K1200RS - Possible supercharger conversion
Turbo Mini Forums

Does the line bore need to be done on all mains or would it just need doing on the damaged one if I can source a good second hand replacement cap to match it with?

I guess the machine shop will be able to tell me if the block is able to be saved / brought back to round or not....

All of them will need doing.

A RTS will take whatever power/torque you throw at it.

In the 13's at last!.. Just

Do we know anyone who's managed to slip one yet?
We had 2 x 998 springs an AP Bonded plate in the van and up to 25psi and didn't slip it.
Could it mean that using thicker springs is overkill?

If something is worth doing, it's worth doing half of.

Mine is definitely overkill. It's a 1275 and turbo Spring. I reckon 2 998 springs would be better.

In the 13's at last!.. Just

only roberts slipped one, but it was worn out...

yup , its true joe, i did .

but it was not worn out , it was just the stock turbo metro plate , with the ap one in there its been fine to somewhere vaguely between 230 and 260 lbs/ft .

with the stocker in there it didn't so much slip it more spectacularly give up the ghost ,like the car was in neutral.


regards
robert.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Thinking about this again. How would a line bore be able to fix this:



The shell has dug into the block and there is a very slight lip that you can just make out in this picture. I can see how you could take material out of a cap, but surely nothing can be done with the block side unless im missing something?

Edited by nky_84 on 2nd Mar, 2016.

I was under the impression that you take some material off the cap making it shorter then re-bore with the crank centre-line higher in the block.

It can have an impact on drop gear clearences and I think some companies do timing chain kits especially for line bored engines.

If something is worth doing, it's worth doing half of.

looks way too deep to clean up with a line bore,

typically you take a few though off the cap, you can then take the cap back out to std,

on s std lump i would consider running wth a groove, but it will compromise heat transfer away from the bearing slightly.

IIRC Smokey Yunick used to always say you need to line hone as it give cooler running bearings over a line bore

hmm, anyone got a fresh 1380 A+ drilled, tapped and dry decked to take a twinkam by any chance.....

Doesnt look to bad to me. A line bore might not clean it all out, but it'll likely be better than it is now, besides that, its in the top half that takes little load. Personally, id have been more worrued about the damage first time round than just the score in the bearing housing.

Like i said its all down to what it measures. I dont think you need to get the score mark out, but you do need to clean the rest up. Its all down to the numbers, you can take a fair bit off the block and caps but obviously the more you take the thinner they get and your moving away from ideal.

If it were me id just junk it and use a different one (and i can do the work for free!) Its not a easy or quick job to do properly and the cost of a block is much less than a line bore and hone.

Also for the record it won't affect drop gears as the crank to gearbox relationship stays the same. You will find the timing end will start to move out of alignment if you take a lot off and obviously pistons run higher in the block. I dont think you would have problems with a timing chain, just a bit more slack in the chain but with my SC K-head setup i can see the seals weeping.

Ive managed to slip mine, that was on full boost flooring it in 2nd gear.

https://www.facebook.com/pages/Fusion-Fabri..._homepage_panel

www.fusionfabs.co.uk



1/4mile in 13.2sec @ 111 terminal on 15psi

what's full boost?

Team www.sheepspeed.com Racing

And what springs/plate do you have in yours?

In the 13's at last!.. Just

Well im glad to report some good news for a change!

Its been a mad rush to get everything built back up and run in before the first event of the season but everything went well and the car gave me a full weekends motorsport which was something id failed to experience for a long time!

I got the car built up and run in on the rollers where it was running just 0.5bar and a conservative timing map. It made 105bhp at the wheels.

Whilst i was there, i discovered that i was previously not running any timing compensation for boost, which im certain was a contributing factor to my previous overheating and pretty high power figures (170fly @0.6bar). This coupled with the dry deck meant cooling is well up to the job now! For anyone running a SC Typhoon ECU, make sure you fill out the spark advance MAP compensation table!

I'm going to go back to the rollers in the next few weeks to tweak the map properly and start to raise the boost levels to unlock the full potential and see what she can do!

Even at this low boost level, the car was competitive (within a second of the class record) and all but the very quickest impreza's and a very nice Noble and Lotus 211 didnt know which way the mini went.

Would love to say i caught this over ambitious turn in speed on cold tyres:


but i didnt








maybe for the next event i'll get round to painting the front and properly setting up the suspension!

With more boost i think class records are a distinct possibility

Thanks for all the help and advice guys, dont think i could have done it without turbominis community!

cheers,
Nick

Looks great, anymore pictures of it?

Well done, the perseverance is finally paying off.

Looks great mate, So what did you do about the block in the end? Or have i missed it.

is that Kames?

i got a new block in the end. Specialist Components managed to turn round a freshly bored and machined block in about a week which saved the day.

Rob - that is indeed sunny Kames.

great to see its starting to do what it should!

I'm a bit supprised by 105hp atw on .5 bar, thats basically NA lump teritory, although if its competitive maybe its a conservative RR.