The carbon fibre time attack/superlap MX5 NB twins blog

lightyear · Postby **lightyear** » Mon Feb 13, 2012 1:59 pm

The conditions where pretty much the same all day, VERY strong head wind down the straight, but otherwise perfect. The car did a 1:58.5 without the aero and on r specs. The same setup did 2:01.7 with starspecs, and 1:56.7 with aero anr r specs. So looks like the r specs are worth at least 3 seconds (they are wider, and on wider rims too). The aero then is worth around 2 seconds. It feels so much better with the aero, i think i could have held it flat around turn 1 at about 190+km/h. I was backing off less and less, and it just hung on. In the morning i was using the brakes, in the arvo it was a brief lift as i was going into the corner. It is so much more fun to drive a car that isn't sliding, and fighting you on every corner.

Guran · Postby **Guran** » Mon Feb 13, 2012 2:16 pm

lightyear wrote:It is so much less challenging to drive a car that isn't sliding, and fighting you on every corner.

Fixed that for you. :wink:

lightyear · Postby **lightyear** » Mon Feb 13, 2012 4:32 pm

It would be less challenging if you did the same lap times as you did on non r specs. But if you think it is less challenging going 3 seconds (or 5 seconds in my case) faster your dreaming.

Guran · Postby **Guran** » Tue Feb 14, 2012 1:24 pm

Nope I'm not dreaming Dave :lol:

. I regularly swap from R-specs to street tyres on my car, and the difference in laptimes is 2 seconds at Wakefield Park (probably more at Phillip Island, as you've found). The R-specs are faster, but I find that I have more fun with the street tyres because they have less grip. Extracting the maximum while skating around all over the place is a huge challenge. Personal preference I suppose.

Postby **beavis** » Thu Feb 16, 2012 8:33 pm

In terms of having fun, I agree, slideways on crappy tyres is the way to go.
But for enjoying a track car, I'd prefer smooth balanced driving on sticky rubber.

Postby **beavis** » Sat Feb 18, 2012 1:39 pm

lightyear · Postby **lightyear** » Sat Feb 18, 2012 1:44 pm

Doesn't look very impressive does it.

Guran · Postby **Guran** » Sat Feb 18, 2012 5:49 pm

Looked impressive to me! Going off at turn 1 must have been a massive brown moment for Brendan. Well done Dave in backing off and avoiding the risk of Brendan's car spearing across in front of you.

Man those Skylines were slow in the corners! :roll:

Postby **beavis** » Sat Feb 18, 2012 7:00 pm

Don't take the video with the skylines too seriously, it was the last run of the day and we were just having some fun.... Surprisingly their corner speeds are about the same as the mx5 in many places.
They both do around 1:51 at PI.

lightyear · Postby **lightyear** » Sat Feb 18, 2012 8:07 pm

And it was the out lap.

lightyear · Postby **lightyear** » Tue Feb 21, 2012 6:02 pm

I dropped the car off for the exhaust today. And decided to remove the body so it doesn't get damaged.

lightyear · Postby **lightyear** » Fri Feb 24, 2012 2:21 pm

The morning after i took the car down, he rang me up and said he has too many cars and can't do the exhaust. And i have to pick the car up straight away. Same old story with that guy. I forgot how unreliable he is. So now the car is back at home and i am tacking the (full stainless) system together. 3" is a lot harder to fit in an mx5. I ordered the muffler, and it should be here monday. Then i will drop it off to him to get it tig welded. The exhaust runs down along the tailshaft like normal, but turns out the passenger side just before the rear wheel. That's where the muffler will be. Then i have to cut a big hole in the lower 1/4 panel/rocker panel in front of the rear wheel (only bit left that isn't cut off) for the exhaust to exit. Also need to cut a hole in the c.f.

bruce · Postby **bruce** » Fri Feb 24, 2012 2:33 pm

And here I was thinking that section of the body had too much metal!

deviant · Postby **deviant** » Fri Feb 24, 2012 2:44 pm

lightyear wrote:The morning after i took the car down, he rang me up and said he has too many cars and can't do the exhaust. And i have to pick the car up straight away. Same old story with that guy. I forgot how unreliable he is. So now the car is back at home and i am tacking the (full stainless) system together. 3" is a lot harder to fit in an mx5. I ordered the muffler, and it should be here monday. Then i will drop it off to him to get it tig welded. The exhaust runs down along the tailshaft like normal, but turns out the passenger side just before the rear wheel. That's where the muffler will be. Then i have to cut a big hole in the lower 1/4 panel/rocker panel in front of the rear wheel (only bit left that isn't cut off) for the exhaust to exit. Also need to cut a hole in the c.f.

I hate service like that!

You might not need much of a muffler. My turbo race car had something of a similar design to your plan but ran straight back from the down pipe rather than over to the centre of the car. It had a hot dog muffler under where the passengers feet would be and then just turned 90 degrees and out the side.

It was surprisingly (dissapointingly) quiet!