Main strap
Turbo Mini Forums

Is this guy talking b*ll**ks or not?



http://www.calverst.com/articles/Engine%20...ap%20issues.htm

I'll be turning my next n/a engine up to 8k without a strap without concern, on the advice of a well respected race engine builder.

For the 16v turbo I will probably only bother with a strap.

Edited by minimole23 on 6th Jun, 2010.

I've stopped using straps. Let's see how it goes.

I totally agree with him, the best thing to do is stud the centre main. I know quite a few people that used to race mini's etc they have all said never fit a centre main strap, just make sure the whole rotating assembly is balanced well. The only engine I have ever had a strap on ended up snapping the crank.

Where do the studs come from joe?

they are minispares uprated S ones,

I had to mod them to fit inside the non S main dowels.

How did you have to modify them dude? (if you don't mind me asking)

ohhh, errrr, racks brains to remember...

The S studs have a fat section where they meet the block rather than use dowels, Stupidly I thought the fat section was going to be the same size as the dowels in the non S but they are smaller, and also longer IIRC.

I just poped them in the lathe at work and took a lick off the fat bit till they fitted through the dowels.

I "think" I counter bored the thread in the block slightly to take the fat section of the stud, but still leave the bit the dowel sits on.

TBH it was all a bit of a faff, I should have just bought ARP stuff....

its not just a case of fitting the studs though is it? you have to cleaarance the gearbox case as well

So what's all the fuss about using straps then? and all this 4 bolt steel cap malarky? Does it actually make any difference?

The standard BL item does seem pretty chunky and up to the job.


Just want to make a decision for my engine as i'll be turning it up to about 8,500 revs occasionally.




EDIT: all opinions good or bad are appreciated/taken on board!

Edited by Owen on 7th Jun, 2010.

I thought centre main straps were for drivers, who slammed it down the gears to slow down instead of using the brakes.

In boost we trust

I have strapped both of my engines and the vans engine and used uprated bolts with washers.

In my opinion the standard cap is up to the job providing the rotating assembly has been balanced, I just use the strap is an insurance policy.

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

Going by the description in the link, I can't drive so a strap is necesary in my case.

I would personally use a strap if turning to over 8k.

When the time comes I will get one of fastcarl, as they seem to be properly thought out - i.e long bolts and hardened washers, rather then churned out like many others that seem to be available.

Edit: I've been researching this to death recently planning my next engine!

Edited by minimole23 on 7th Jun, 2010.

I've got some of the Finnings CAT bolts from Carl and they are very nice. Everyone that sees them wants them lol.

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

Perhaps stig is referring more to an over-rev situation causing the crank to flex Sprock?

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

N/A

1430cc, 320 cam, weber 45, MED hi lift rockers, megajolt etc

In boost we trust

I seriously doubt it!