how much power ?

[20B_boy]

Should be good for single figures - mpg I mean! A lot of the single turbo 20B\'s running not much greater than stock porting make <10mpg as it is. Dont here of many bridgeport 20B turbos either - either big extend ports or PP\'d it seems - not sure why. Perhaps 3rotor BP\'s experience intake \'issues\' like some PP turbos are meant to???

Bri, Geffs 1/2 BP was a lovely drive - until you get around town obviuosly. The most annoying things about them is as Chris has menitoned - driving them off load/light throttle - they dont like it much. Geff\'s bucked about quite badly at times when trying to cruise - you find your self doing a lot of shifting, slowing down, accelerating etc in order to keep them on load...

[bnaellis]

Hi Rich,

I don\'t want one for a daily driver, just as a company show car
and hopefully a skyline whipping machine at next years santapod event:D

[20B_boy]

Yeah, I realise its not for a daily driver

They are fine to drive - you just have to keep in the throttle to keep them happy!

Skyline whipping machine? a \'bit\' of work required there I\'m afraid. They were running low 10\'s this year so will no doubt be in the 9\'s next year. Even with slicks thats going to need SERIOUS engine and drivetrain mods to get any where near in an FD...

A 500ATW FD in full trim on slicks would pull...well significantly more than 9.5s!
 
R.

[Grizzly]

I think were at least Two years behind the skylines, give it a little time for development and a bit of Knolage to be obtained and who knows?

Chris

[20B_boy]

Absolutely Chris. We need to be patient whilst the technical knowledge base grows over here. One day we will get there. It will cost plenty of motors - and people will come and go in the mean time, BUT - ONE DAY - The Rotary will be doing the butt-kicking at the strip in the UK - and I know a good few of us here will still be there to see it

Oooo, I\'ve come over all emotional

[John Yorke]

Interesting read in Banzai this month Ralph Friend @ Costom Groundzero [name sucks!] is claiming 650rwhp @30psi!! on a T72 interesting that he has used datalogic and done a 4 way ignition map - mind you he is running on 106 octain:bandit  Only in the US of A a?

[bill shurvinton]

Did some sums on the turbo calculator at //www.not2fast.wryday.com that my mate Eric wrote. Basically it confirmed what Carl was saying that you need a motor that will do about 250HP in NA form to get 500 at 18-20PSI.

Now just think about that a while. Ever seen 250HP off a stock inlet manifold? Now generally these things are not seen as a problem by the turbo crowd as you just add more boost, but we are talking about low boost levels compared to sierra cosworths, skylines and the like. With a rotary you have to play by slightly different rules and build the best NA setup you can then add boost.

The downside of this is that you can end up with the worst that a large overlap high revving engine and a turbo can give. After all a bridge or PP turbo goes against most of the rules. ( it shouldn\'t work but I have some ideas why it does.)

Now there is no reason that a good street port the right inlet and a properly designed exhaust shouldn\'t give around the 230HP mark after some considerable optimisation. This with 18PSI should be around the 460HP mark whilst still being a very well behaved car on the road.

Problem is the right inlet........

[bnaellis]

I don\'t think all bridges run that rough Rich I seen and heard Geffs, I know that does, My mate Erdin has a half bridge which runs well rough which I have also driven in . I believe both of these cars idle at 1,600 rpm and as you say when they are driven or tried to be driven normally they buck like a bucking bronco.
When my one is warmed up it idles at 1,100 rpm the idle is also quite smooth it does not fluctuate by much I don\'t get the bucking what I experienced in Erdins either. I don\'t know if this is to do with the tuning or how of the actual bridge itself?

Well I went down to rxmotors yesterday and was doing some tuning on this beast had the boost turned down to only .8 bar
This car is an absolute bullet still need some more work on the fuelling as when we get into the high rpm with foot to the floor
air/fuel ratio is below 10 and it gets a bit choked but it started getting a bit too late to finish off yesterday but. once power is applied it does not run leaner than 12.5 but needs leaning out a bit in the higher rpm and boost range. I am temtped to keep it for myself again, How about we up the stakes on the first car to do sub 12sec 1/4 then I\'ll sell it after:D
Car is laggy, but depends on what gear your in how bad it is. In 3rd gear at approx 30-40 mph you can floor it and nothing happens for a while then the car just goes mental. but going up thorugh the gears it\'s not too laggy. It\'s hard to tell what rpm the turbo is really on song as when it kicks you\'s have to be some kind of nut to take your eyes off the road. Can\'t wait to whack the boost up to what 18 psi but is a little too damp at the mo for  that. Will keep all updated on progress.

rgds

[bill shurvinton]

Whatever bridge you have there will be a degree of self-EGR going on as the inlet never closes. In a weber equipeed car you also have reversion to deal with, which is not an issue if you have seperate primary and secondary throttles.

There is no real away around this unless you start doing things with 6-port side plates.