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2900lb is lighter than my R33 and I run 13-14psi in the Nitto's.  I'd try 18psi in them to start with and *maybe* drop it to as far as 12 from there.  Obviously you'd do that in increments to guage the best pressure.

As far as burnouts go, I have never been one for massive smoke-shows.  In fact, I have read on American Supra & Mustang forums that the BF's require only a small burnout to get them to an acceptable operating temperature.  

Also, you should find that you don't have to do as big a burnout as the first one during the course of a day.  They do actually retain some heat.

In terms of launching, I have absoluteley no idea what will work well with your car.  Good luck mate!!

Adrian

Adrian, yeah thanks mate. Before the current batch of mods I took the M Coupe to a weighbridge and got 3,219 lbs with a full tank or fuel and a full (5 litre) washer reservoir, but without me.

I've pulled a shitload of stuff out of it and hope to have it down to 2900 lbs with no water in the washer, no passenger seat and 1/8th tank of fuel (ie race prepped). I'll get it over the weighbridge soon to confirm.

The DRs are 50 series on a 15" diameter so they should have a lot more sidewall than my street tyres (285/35 R18). I'll take your advice and start at around 18 psi and work down (or up?).

It's all learning for me, so here's hoping the DRs turn up on time!

Adrian, yeah thanks mate. Before the current batch of mods I took the M Coupe to a weighbridge and got 3,219 lbs with a full tank or fuel and a full (5 litre) washer reservoir, but without me.

I've pulled a shitload of stuff out of it and hope to have it down to 2900 lbs with no water in the washer, no passenger seat and 1/8th tank of fuel (ie race prepped). I'll get it over the weighbridge soon to confirm.

The DRs are 50 series on a 15" diameter so they should have a lot more sidewall than my street tyres (285/35 R18). I'll take your advice and start at around 18 psi and work down (or up?).

It's all learning for me, so here's hoping the DRs turn up on time!

Your 18's should have about 50mm top and bottom (100 total) whilst the 15's have more like 69mm top and bottom. That's 5.4" total sidewall compared to not quite 4" with the 18's.

Much better :)

Start at 18psi and drop it 2 psi at a time using your 60' times to check your progress. Try a couple of passes at each level to make sure. It's a LOT easier to take pressure out than it is to put back in :D

Oh and benm, whatever do you mean? I don't waste rubber and destroy the environment like that?!?!

Adrian

Your 18's should have about 50mm top and bottom (100 total) whilst the 15's have more like 69mm top and bottom.  That's 5.4" total sidewall compared to not quite 4" with the 18's.

Much better

Start at 18psi and drop it 2 psi at a time using your 60' times to check your progress.  Try a couple of passes at each level to make sure.  It's a LOT easier to take pressure out than it is to put back in :D

Adrian, the BFGs have been picked up by the couriers in Melbourne so they are now expected at my workshop Monday 21/6 ready to be mounted.

I'll bring the truck with compressor out next time so I can add some tyre pressure in the pits. Thanks for the tip about starting point for tyre pressure; I'll take your advice and start at 18 psi working down.

Mickey Thompson also make ET Street Radials in 26 X 11.50R15 (26.1" tall, tread width 10") and ET Street 26 X10.50-15LT (26.1" tall, tread width 8.3") so there are other options.

The challenge now is to get some 4" x 15" front runners made up that will clear my 13.5" rotors and calipers on the front so I can run 26.0 X 4.5-15 (25.9" tall) ET Fronts. What pressure should I run in the front runners?

Mickey Thompson also make ET Street Radials in 26 X 11.50R15 (26.1" tall, tread width 10") and ET Street 26 X10.50-15LT (26.1" tall, tread width 8.3") so there are other options.

Rocket Industries told me that they had an expected date of arrival for the first lot of ET Radials of, "July...errr...maybe later...we dunno." The ET Streets are DOT rated but not radials like the BF's and Nitto's.

The challenge now is to get some 4" x 15" front runners made up that will clear my 13.5" rotors and calipers

I honestly wouldn't worry about them, mate. Put 45psi in your regular front tyres for less rolling resistance. You wont have the instabillity problems with the BF's on the back as they're radials and suffer none of the wandering and rolling problems of slicks. No need to run conventionals on the front.

No idea what pressures people run in front runners though, sorry. Never used slicks before.

Adrian

I honestly wouldn't worry about them, mate.  Put 45psi in your regular front tyres for less rolling resistance.  You wont have the instabillity problems with the BF's on the back as they're radials and suffer none of the wandering and rolling problems of slicks.  No need to run conventionals on the front. No idea what pressures people run in front runners though, sorry.  Never used slicks before.

Yeah the streeters are OK for the drag radials but I need front runners so I can run the slicks I already have. I don't want to be booted for running radial fronts with slicks in the rear.

Went to the wheel guy today and there's no way to fit 15" wheels over my big brakes. I'll have to go 16" wheels so I can't run MT ET Fronts which is a disappointment.

Trying to find a 16" crossply tyre that will fit on a 4" wide (or thereabouts) rim AND is about 26" tall. There's bugger all .. it's been suggested to go for a motorbike tyre ..

Any ideas?

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