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  • 3 weeks later...
On 20/12/2016 at 2:24 PM, Kinkstaah said:

I stupidly suggested to my gf that a MX5 would be a perfect car for her to get a head start in, learn on, use, etc. 

Now I want one, with a small turbo albeit.

LS Swapped FD would be great, but if you want a ~1250-1350kg car with an easy to use 250-270kw then you start looking into options like, oh I dunno, a RX7.. or a jap turbo import made by Nissan...

I have this discussion with my housemate who got an E36 328i with plans to put a LS1 in.

I got bored the other day so did some quick power-to-weight calculations:

Given that the 4door is about 1430kg dry with a manual box (according to 'sources' aka the internets) my current power-to-weight is roughly 192rwkw per tonne.

To get to the same in an MX5 you'd need:

  • NA series – 180rwkw
  • NB – 204rwkw
  • NC – 213rwkw

So naturally aspirated is pretty much out the window. Given the size of the donk you'll probably need forgies too = $$.

For comparison, in an S13 you'd need 235rwkw, which should be reasonably easy with a sorted SR20DET?

So perhaps OP already has the perfect track car? :)

Obviously power-to-weight is just part of the equation, but still...

Actually the MX5 engines (at least the 1.8) is known to hold a good 200rwkw, there's plenty of people out there with a turbo, some guy has gone full John Richardson at 191 rwkw and has done something like 60 track days on it. Seems about 180rwkw in a MX5 is similar to the "300 is safe" kw in a RB25.

And then you go to a corner or brake and instantly lose 400KG of weight.

But no, the S13 with a modest power setup and sorted handling is a very good option as well. You only really get problems in any car if you decide HOLY SHIT POWAAAAAAR or decide you want slicks and then you get oil control fun. I mean shit the S13 gets blame for being a bad chassis, but someone won WTAC with one. Not a very stock one albeit, but it can't be that bad for fun and games!

  • Like 1

I think the mx5 guy your talking about with 191rwkw also had an Na one with 90 something rwkw and was still very very competitive. Turbo did 1.22 -23 around sandown and the Na did 1.25-26 from memory. The performance came from weight reduction. Anything that could be removed was and everything else lightened. Think fibre glass panels, carbon roof, carbon drivers seat etc. Very impressive what those little things can do but just like anything $ need to be spent. Skylines and Silvias are still great track cars and can be made very quick without mega $ spending. Think, richos r33. That is 1 quick machine that cost a modest amount focusing on the things that needed to be done. He could make that thing substantially quicker with bulk $ put into it.

  • Like 1
22 hours ago, Kinkstaah said:

Actually the MX5 engines (at least the 1.8) is known to hold a good 200rwkw, there's plenty of people out there with a turbo, some guy has gone full John Richardson at 191 rwkw and has done something like 60 track days on it. Seems about 180rwkw in a MX5 is similar to the "300 is safe" kw in a RB25.

And then you go to a corner or brake and instantly lose 400KG of weight.
...

Fair enough :)

21 hours ago, admS15 said:

I think the mx5 guy your talking about with 191rwkw also had an Na one with 90 something rwkw and was still very very competitive. Turbo did 1.22 -23 around sandown and the Na did 1.25-26 from memory. The performance came from weight reduction. Anything that could be removed was and everything else lightened. Think fibre glass panels, carbon roof, carbon drivers seat etc. Very impressive what those little things can do but just like anything $ need to be spent. Skylines and Silvias are still great track cars and can be made very quick without mega $ spending. Think, richos r33. That is 1 quick machine that cost a modest amount focusing on the things that needed to be done. He could make that thing substantially quicker with bulk $ put into it.

Very good points Bill. Those N/A times are insane, must be a great driver and a very well sorted car. It must be so much easier on all parts carrying that much less weight around, which should help with reliability.

So I think my ideal track car then is a fully sorted 200rwkw turbo MX5 NA pre-1992 in club plates so you can drive to/from events. For $10k please :) 

Very good points Bill. Those N/A times are insane, must be a great driver and a very well sorted car. It must be so much easier on all parts carrying that much less weight around, which should help with reliability.
So I think my ideal track car then is a fully sorted 200rwkw turbo MX5 NA pre-1992 in club plates so you can drive to/from events. For $10k please [emoji4] 

10k order 1 for me too please[emoji106]
  • Like 1

Thoughts on this MX5?

http://www.my105.com/ListingDetails/p/1/k/mx5/id/17404

 

I like the idea of swapping for something a little easier to manage and cheaper to run. LS1 with an RX7 also sounds interesting. Does it drop straight in?

Is Sports Sedans the only place you can run something with an engine swap?

In a CAMS sense, improved production allows an engine swap for same manufacturer/same number of cylinders. but yes you'd need sports sedans for a nissan 4 cylinder in an mx5.

Thoughts on this MX5?
http://www.my105.com/ListingDetails/p/1/k/mx5/id/17404
 
I like the idea of swapping for something a little easier to manage and cheaper to run. LS1 with an RX7 also sounds interesting. Does it drop straight in?
Is Sports Sedans the only place you can run something with an engine swap?

I reckon it's awesome but would be pretty tough to engineer for rego I'm guessing
  • 2 weeks later...

I reckon it's awesome but would be pretty tough to engineer for rego I'm guessing


LOL I was actually looking at it for myself apologies! No need for engineering as it would be a track car only.

I've been giving this some serious thought as the GTR is in a pretty good state to sell as literally everything has been refreshed on it, and the 32 market is on the up.

I was actually fairly close to securing a trade on an SR3 but it fell through. But I did do quite a bit of research on them and liked what I found. Much as Ben noted with the Radical, all parts are 'lifed' and replacing anything costs a fortune. So can't break anything which rules out door to door racing, however running it as a track car is definitely affordable. Also you can source a used hayabusa engine and chuck that in for a fraction of the cost of a sealed engine.

The other cars that interest me are ICV's. Only thing that concerns me is safety. Rollover protection looks suss and hitting a wall at 200kmh in a metal coffin welded together by a bloke in a shed doesn't exactly inspire confidence. Does anyone know more about them?

Also, mx5's are rad. My first car was an NC it is still one of the best cars I've ever driven. Needs a snail though
  • Like 1

Oh wow someone's combined a (turbo) MX-5 and an open wheeler: http://jalopnik.com/driving-a-stripped-down-turbo-miata-kit-car-doors-are-1791238438

You basically move your NA/NB running gear over to a tube chassis and lose about 1/3 weight in the process. Looks like heaps fun.

The Exocet kits start at $7k US, which is actually pretty good. No idea whether something like this could be engineered in Aus. Great idea nonetheless!

sgfr6hvvob7gytxnk2ns.jpg

 

4 hours ago, V28VX37 said:

 

Oh wow someone's combined a (turbo) MX-5 and an open wheeler

 

There is a link on page 1 of this thread to an Exocet....

Edited by GeeDog
  • Like 1

My knee jerk intrawebs review of the Exocet is it's rubbish but perhaps it reminds me of dickheads in Clubmans who apparently think it's cool to try to take your apex, next time I'm turning in track rat.

Serious? Would need mudguards wouldn't it? That could be a problem, nothing to hang them off.

  • Like 1

FYI looks like the Exocet distributor in Aus has gone under and ripped a few people off by the sounds of it. 

Would make for an interesting track car, wonder if it could run against the clubbies in supersprints 

  • 2 weeks later...

We've run a Stohr WF1 for a few years-- by far the fastest car per dollar you can drive.  54's - 56's at Wakefield, 1:25's to 1:27's at EC.  Some of the numbers earlier in thread ($3k per day?) are seriously off the money.  The car has a GSXR1000 engine which you can buy for about $3k complete.  Race prep is relatively cheap, the thing is somewhat simple really, most of the tech is in the aero.

  • Like 3
13 hours ago, LSX-438 said:

Some of the numbers earlier in thread ($3k per day?) are seriously off the money.

Sports Racer Series (per event)

$1,900 = New Tyres

$500 = Mechanic / Pit crew

$100 = fuel

$1,895 = Event entry fee

Total = $4,395

 

Radical Australia Cup (per event)

$1,900 = New Tyres

$500 = Mechanic / Pit crew

$100 = fuel

$3,975 = Event entry fee

Total = $6,475

 

Now of course, if you just want to do club trackdays or super sprints that total per event comes down to around $500

 

  • Like 1

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