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Race juice: hardened valve seats?
Philbo - 26/2/03 at 06:07 PM

OK, I'm a newbie and probably tomorrow I will start my collection of bits to build a Locost for trackdays and maybe 2004 racing, once I learn my arse from my elbow.

Racing regs stipulate that only pump fuel can be used: what do people race on? LRP or the 98 octane stuff from Shell - presumably that requires hardened valve seats to be installed in the engine?

Also looks like I will use the GT 4-speed 'box, but I have heard about the necessity for a 'diff collection?! Anyone prepared to share which ratios are required?

Thanks, you'll probably be hearing a lot more from me as the build gets under way.


Locost26 - 28/2/03 at 10:13 PM

Phil

For fuel in the race series, alot of people now are using shell optimax, the regs do alow hardened valve seats to be inserted, if you go to the 750mc site it gives all the regs there.
If your'e not going to be doin the engine yourself, it might be an idea to get a prepped head from somewhere like vulacan engineering, good value for money and ive no problems with any of their products.

As for boxes, the majority of the grid run with 4speed boxes, as for ratios well you will be lucky if anybody admitted there ratios, but most people run standard. For diff's people only normally run 3.9 or 4.1

If you need any advice for racing issues give me a buzz


Philbo - 2/3/03 at 08:50 PM

Thanks for coming back. Have now sourced engine and gearbox, will check it out for work done (it has already been race tuned but still has standard parts). Looks like hardened valve seats will be the way to go, the 98 octance juice will allow more aggressive timing than LRP so looks like it's a no brainer.

Have 4 speed GT box so will have to see how that does. Have 3.9 diff but not 4.1, which cars/models did that come on?

Better get on with the build, looking forward to it as a first project, expect to see me in 2004...!

Good luck with your racing.


racingdick - 4/4/03 at 12:25 PM

talking of engines, does anyone know the lift of the gt camshaft, and if there is a late gt cam with different lobes.

Also hows Tim Grays car so damn fast??!!


racingdick - 4/4/03 at 12:29 PM

i mean a 20 second lead?? and finding atleast 2 seconds from race 1 to race 2


Mark Benson - 4/4/03 at 03:02 PM

Best not to go there I think.....

In his defence, he has been racing Radicals at Donnington all winter I believe (and he was in the Scrutes bay for a long time after Sundays final).


racingdick - 9/4/03 at 05:07 PM

okay


Deckman001 - 29/4/03 at 08:08 PM

With regard to hardened valve seats, to save changing a prep'd engine with 'normal' valve seats, can you add a lead additive to the Optimax . I know it's an additive , but not a performance booster

Jason


Viper - 29/4/03 at 08:28 PM

We use Shell Optimax with Millers lead replacement treatment in our classic race cars and the stuff does work well but it costs about £5 per 20 litres, money well spent .


ned - 30/4/03 at 09:58 AM

As long as these additives don't show up as fuel irregularities when scrutineering - I'd suggest having a bottle/receipt for the stuff at the track just in case.