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Where to start for 300+ bhp?

Greetings all

My Ur-q project is moving again, & I should have a straight shell back in
my possesion by Xmas. So its time I started making decisions about the

This is not going to be a street car, thats what I have the MB for, this is
going to be my multipurpose motorsport toy. Under the local regulations,
there are'nt a lot of classes that the car will be competitive in, except
street sedans, club cars & possibly marque sports cars if they'll accept
it. Club cars would be the logical choice but for reg 2.4 which deals with
modified turbo cars being required to run a 36mm restrictor. I dont want to
deal with a restrictor, so it looks like street sedans which run in the
same races anyway.

Street sedans have three rules. The car must be capable of being registered
for road use, must use an approved tyre  & burn "commercially available"
fuel, which includes avgas. Luckily you can register just about anything in
Queensland, the only real problem being noise.

The dominant cars in this class are brigeported 13b rx7's. There is a Ur-q
with maybe 300bhp competing in Sydney, but cant match the power/weight
ratio of the rx7, so I know I need more.

Now the questions. In the workshop is my wr motor, the ex Dave Lawson ABT
head & cam & a AAN short motor that I can have for about us$650.  With both
motors, I'm up for a new set of pistons, the wr's have nearly 100k miles on
them & I think that the aan is probably too high a compression ratio. So is
there any advantage in the blocks? The only one I can come up with is the
aans knock sensor locations, which may prove difficult to reproduce on the

I intend to run Autronics engine managment (similar to motec, but nicer
people), which can easily handle anything from ignition through to launch
control. The exhaust manifold will be a tubular header.  I was suprised by
the quote I got from Gonzo's racing pipes, computer designed, ceramic
coated, less than us$1k. It'llprobably flanged to suit a garrett turbo,
unless someone can actually produce some maps for kkk.

As for the inlet, that depends on which block I use, coz the abt head wont
go on the aan.

Any suggestions greatly appreciated


John Firkins