Tyre help please (or LSD?)

[Andy70]

I just had more upgrades to my 335i also had turbos rebuild and is so much more responsive as a result ( they must have been shagged), however as a result of the restored turbos,uprated intercooler, charge pipe, ported throttle body and now intake pipes the car struggles for grip even before the JB4 box gives me max power available. so, would a very decent pair of tyres on the rear make enough difference? I only have a pair of 130 quid (each) Avon's on the back which were just ok before or do I need an LSD to plant the power down? if so there are more than 1 option for these is the Quaife the only realistic option or are the 600 quid alternatives as good? Also do I need a specialist engineer to fit them? I live in Bristol if anybody knows of a garage that could help. I don't want to get into too much of a debate as to how great an LSD would be as I am aware of the handling benefits, at the moment I just want to put my power down properly. Thanks

Andy

[Andy70]

Thanks Huskyman, I get your point but I have had 2 M3's and at the time never realised they had an LSD, ( sorry back in those days I was ignorant to that knowledge) I tend not to rag my car around bends to the point where I need M3 handling but till135 sounds a bit more sensible to my needs, that's reassuring, thanks. However I do see the benefits of an LSD but like i said in my threat the other day about my turbo rebuilds, I think my missus would wince a bit if I wanted to spend money of those at the mo, especially as I just spent a grand on turbo rebuilds and intake pipes ( but I will get one eventually I hope), but just to plant my power down at the moment, that is reassuring that a decent set of tyres my suffice. Just out of curiosity, what are the costs of fitting an LSD? I get the impression its quite a specialist job, or can any mechanic do it? oh and who are Birds? I think I recall reading a thread about them on here the other day, but cant think which one it was

[Andy70]

naturalaspiration said:

You are struggling with the grip in a straight line acceleration or only when exiting the corner (and applying throttle early)?

In a straight line and in the dry. I tend to go careful around corners or you crash and loose your no claims discount :-)

[Andy70]

Huskyman said:

kitsand
Birds have the exclusive rights to supply the Quaife diff for the BMW range. It is quite a specialist job and I believe birds do a fitting service, have a look on www.birdsauto.com
They do understand about setting up a car, I had one of their B3 suspension kits and it was superb.

Oh right I see, thanks for that. I'll have a look. But you can buy a Quaife diff off ebay for just over a grand, where would you get that fitted if you live miles from Birds? (or is a grand expensive?)

[Andy70]

Interesting points, I want a diff now, but that will have to wait I think after just spending a grand on hoses and turbos, I think I may as well buy some new wheels to go with my new tyres as mine have the odd crack in them so seems silly putting tyres on them, so that's another grand. I seen an ad for refurbed BMW wheels for 500 quid, so I may get some. As long as I have some reassurance that a decent set of tyres will provide good grip for now, they will have to do for the time being. Cheers

[Andy70]

RobM77 said:

I had a Birds suspension kit on my last car, an E90 3 series, and I agree with the above poster - it was absolutely fantastic. That, along with decent tyres, will make a fairly big difference. Onto the LSD though.. I've driven a number of 1 and 3 series cars without LSDs, plus M3s with them and I've got a quaife LSD in my racing MGB; based on that experience, from what you describe I think the Quaife would solve your problems overnight. Not cheap though! Generally the rule is to sort out the tyres and suspension on a car first, as you've discovered.

Lovely Rob, thanks

[Andy70]

aeropilot said:

If he hasn't got a LSD, then both wheels are unlikely to be spinning at the same time

Given the OP's posts, in that his preference is only for going silly fast in a straight line only, your suggestion of being a 'bit light in the loafers' is the best suggestion for his issue.

I'll try changing the tyres and see what happens, wheels too ought to be changed as well as I been told they have a couple of small cracks on them, no point in putting new tyres on wheels knowing they aren't in the best of health. Bit of a gutter as Avons aren't old and they were just ok most of the time. I would like an LSD but that will have to wait now I know decent tyres should at least help

[Andy70]

gizlaroc said:

Andy70 said:

naturalaspiration said:

You are struggling with the grip in a straight line acceleration or only when exiting the corner (and applying throttle early)?

In a straight line and in the dry. I tend to go careful around corners or you crash and loose your no claims discount :-)

Have you got different tyres front and rear?

For a start I would make sure they are matched. RWD BMWs can become a twitchy mess and the traction can kick in all the time with different tyres front and rear.

This has been discussed ad infinitum over the years on the M3 forums, no one believes it, in the end after trying everything else they put on 4 matching tyres and BINGO!
The car is planted, the traction stays of unless really pushing it hard, and life is good once more.

The suspension is just fine as far as I know, I do have 2 different pairs of tyres, Pirelli on the front and as I said in my original post I suppose they would be very bottom end branded tyres, Avons, so wondered if top end tyres would give me better traction, not sure how the same front tyres would give me better traction at the rear? As I said I choose not to go silly fast around corners, I didn't say the car couldn't, it handles very well (probably) lol the car was fine (just) before the increased power, it did struggle a bit in the wet now it struggles in the dry too

[Andy70]

Anyway, till 135 was good enough to recommend Michelin pilots, as I generally never follow the tyre threads I'm sorry to say I do miss out on the great tyre debates as in the past its never really affected me, but now it obviously does, so any advances on those for general traction? I'm off the runflats by the way, they are far too hard and crash over the bumps in my opinion

[Andy70]

Update. Got 2 new Michelin pilots today (255/30/19) for the back and noticed difference straight away loads for traction so all sorted, thanks for all your tips