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If Adz or Geoff reads this, how much difference is there between driving on the semis and road tyres at PI???

I know there is about3-4 seconds per lap, but the feel of the car on the grippy rubber. Would you say easier, scarier? My gut feelign is i wouldnt use semis for the first time at PI....tryign to re-learnt he levels of grip on a fast track could end badly

I did PI last year but only got a few laps before the outlet pipe off the turbo split in half and ended my day. As jack was saying I couldnt hold much corner speed with the road rubber, also because I had my old suspension setup last time 2.

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Yeh i know tyres make a huge difference to lap times...but i suppose im just goiign back to the first time i ran semis at Eastern Creek, i so wish i had of tried them for the first time at the slower Wakefiled, as pushing the car through turn 1 and the final turn onto the straight trying to explore the new grip levels was kinda scary, as when they let go, the let go way quicker and the car wa harder to catch.

..anyway, it seems others have not had this problem, so ill shut up now :)

I still say want to get back to PI with my car with current mods. I still think it will comfortably do a 1:52 :)

If Adz or Geoff reads this, how much difference is there between driving on the semis and road tyres at PI???

I know there is about3-4 seconds per lap, but the feel of the car on the grippy rubber. Would you say easier, scarier? My gut feelign is i wouldnt use semis for the first time at PI....tryign to re-learnt he levels of grip on a fast track could end badly

5 seconds is easy, but that was taking it cautiously on a generously offered set of D01J's. I also had a blown rear shock so I'd suggest 7 seconds with a predictable setup and confidence in the rubber.

ADZ was on stock suspension and I was on lowered stock with RSR springs, so if you can make 2:00 on street rubber then you are ready for semi's. That day though we were doing 2:03's and dropped to 1:58's. The 3 seconds was a change of the pedals for heel-toe and Dunlop SP 9000 tyres on the rear.

Yeh i know tyres make a huge difference to lap times...but i suppose im just goiign back to the first time i ran semis at Eastern Creek, i so wish i had of tried them for the first time at the slower Wakefiled, as pushing the car through turn 1 and the final turn onto the straight trying to explore the new grip levels was kinda scary, as when they let go, the let go way quicker and the car wa harder to catch.

..anyway, it seems others have not had this problem, so ill shut up now :)

I still say want to get back to PI with my car with current mods. I still think it will comfortably do a 1:52 :)

This is good for me to know too, as most likely I'll be running semi comps for the first time at PI, and I've never tracked my car before...

I've heard varying things about going out on semi's for tracks such as this, as opposed to street tyres. Does anybody else have any more advice/opinions??

Dane

No, I only cracked a 50. I had RE55s and around 250rwkw. 49s would have been possible but require big nuts in turn one. The suspension was stock at the time which made it a bit wobbly in the faster corners...

I reckon you'll do 49s, possibly better.

Last time the boys played tyre swappy's at the Island it was five seconds all round with three drivers getting this increase almost immediatly.

I want to get 49's at the island before I add more power to my car. Aaron did you do a 49 bfore the upgrade?

This is good for me to know too, as most likely I'll be running semi comps for the first time at PI, and I've never tracked my car before...

I've heard varying things about going out on semi's for tracks such as this, as opposed to street tyres. Does anybody else have any more advice/opinions??

Dane

I think it comes back to how comfortable you are with pulling a car back once it steps out. Driving a weak sauce std RB20 with semis, when it stepped out i couldnt oppo lock it without penduluming which got me in trouble a few times. I shouldnt say trouble, but on the grass backwards :lol:

Coming onto the straight at Eastern Creek went from about 105-110km/h to about 130km/h. And with street tyres you could feel it progressively starting to slide and you could slowly catch it. With the semis, it kinda snapped when the tyres let go and i was way to slow windign the lock on then off, it all seemed to happen so much quicker at 130km/h

LOL...i did the exact same thing when pushing to try and keep up with Snowie (in vain) at Sandown last year...turn 4 the car felt fine and i gassed it and i was too busy seeing how Snowie was going on corner exit and i looped it. Caught me by surprise as they are much more a race tyre, where the grip levels change as they come up to temp, and then get too hot. Road tyres just always suck and have no grip :D

My advise for PI...forget turn 1, the final turn onto the straight is the most dangerous. :) No room for error if you catch a bit of dirt on the exit, oversteer over the slight crest they have just before the apex...i know my car wants to and it scared the beejezuz out of me when it did adn i caught ripple strip and dust on the exit :D

Oh, and not to mention the fact you need the camber and roll control not to be cooking th eoutside shoulder liek i do :( ...

...fark forget what i am saying. Im beign an old lady. Get the semis, you will have a ball...it snot liek you will be driving your car with your eyes shut, you will no doubt get a grip of things quicker then i did :)

haha you instill so much confidence!!

I've got a friend who races a 944 at the island, and has warned me about the last turn. The last time he raced there a 944 turbo was written off doing exactly what you said, slightly caught the grass on the way out on his last lap, and hit the wall hard...

oh well, we'll see how it goes I guess!!

I don't like the lines that guy takes through alot of the turns.. just looks kinda unco :lol:

I'm curious - what does the author of the video consider a "big turbo"? What car and year of make is that car (porsche?) and what turbo was it running?

I don't like the lines that guy takes through alot of the turns.. just looks kinda unco :lol:

I'm curious - what does the author of the video consider a "big turbo"? What car and year of make is that car (porsche?) and what turbo was it running?

It was Hung Do. His lines all look good to me. Maybe a little hot into Honda and takes Siberia wider than I like to.

All except his line onto the grass, backwards...

I don't like the lines that guy takes through alot of the turns.. just looks kinda unco :lol:

I'm curious - what does the author of the video consider a "big turbo"? What car and year of make is that car (porsche?) and what turbo was it running?

looks to be a late model 944 turbo to me

looks to be a late model 944 turbo to me

Yeh is it perhaps a 968 with aftermarket turbo, dash looks 968.

As for lines...yeh they kinda were i try to wrestle my car to be but never quite get there :) Honda is about right in my eyes, with the RWD i think its best to have a late turn in, that way you can stand on the power sooner and straight line the exit which helps with power down as you are basically in straight line.

Siberia does seem a little strang though, i would have thought that is a little tight on entry.

Yeh the car getting light where he prangs it isnt my main concern. It isnt really visible but at abut 11seconds into the footage when he is turning in for the final turn. I find my car gets light and darty, as the corner entry is definetly down hill. And again at abottu 18 seconds when your flat letting the car drift wide at exit my car gets a bit light...perhaps you dont feel its as much with the 4wd traction and also the extra bit of weight ?

At first i loved how it has a hell quick entry and you hook in on the racing line and get on the power early and hammer through, there is a real elevation change and kinda feels like a quick roller coaster ride. i scared myself into not trying to maximise my time by carrying corner speed down the straight...im scared ill Greg Murphy it on the outside wall :D

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