where do we go ???

[Steve Kerswell]

Just been chatting/welding with the hill billies down the lane. Their hot rods are coming on a treat . They were commenting on all things "modified" and where do we go next. Even Zetec engines are now long in the tooth, Type 9 gearboxes are getting in short supply so pull a good price. Bike engined kits are great but fragile in the transmission area. Mazda MX5 wont last forever. BMW look like they will keep with RWD, but finding a cheap breaker for reliable use is hard. Electrics are a bit of a minefield nowadays and attract a premium price. How long before we get attacked on emissions? They say the IVA is written in stone, but already I have seen it modified. Historic vehicle stuff is under attack from various quangos. Do we hope to maintain a status quo ???

[Dave Price]

It appears that the Mazda RX8 gearbox is a possible candidate to replace the Type 9.   There are lots of discussions on Ford forums about fitting the RX8 6 speed box.  I have just bought one.  May be I should have asked if anybody else has fitted one and their experience before I jumped in and bought one.

[Steve Kerswell]

I know of 3 now being used, some say they aren't that good, these three love them. Handling 200bhp one claims. Another on a zetec, the third is on a V6 at present that doesn't go all that fast, ever :-))

[Big Vern]

Mazda 6 speed as used in the RX8 and later MX5's are weak compared to the old MX5 5speed. (its essentially a 5 speed box with 6 speeds crammed in it) so the gears are thinner. It is lighter than the type 9 and has better ratios but the 5 speed from the MX5 is better still and easily copes with 300bhp from turbo'd mx 5's :)

[Big Vern]

not for very long, I've blown two up already :o  its not outright hp but the torque and the speed at which it occurs and how hard you use it. The ratios are a bit pants too as its really a 5 speed with two 1st gears

I've switched to the 5 speed for reliability

As for your link " I know of some running  500-600hp" what where? evidence not heresay! You can waste a lot of time and money on internet pub talk. If they were that good the rally boys would be using them and they'd be fetching a grand a piece!

RX8 box is a better bet than using a tired type 9 but as to the value of converting? doesn't make sense to me, just use the MX5 engine and box! anything else seems to be a triumph of engineering over design.

[Big Vern]

I suspect RX8 gearboxes are readily available as there are so many dead RX8's as everyone is too scared to rebuild the wankel engines. (you can get an entire dead RX8 for £350 about the same price as a half decent type 9) Thus the RX8 box makes for a cheap 6 speed. If you head over to the RX8 forums you'll find no end of complainants regarding the gearbox, as Aisin who make the box simply squeezed 6 gears into the space of 5 so they had to make the gears narrower and thus less strong. The bellhousing pattern of the RX8 does make it an easier conversion than any of the MX5 variants but then if you use the MX5 box then why not use the engine that went with it and save on the conversion cost.

[James Doulton]

I think that part of the reason why the guy was making adaptor plates for the RX-8 gearbox was so that owners could put a different engine in when their Wankel packed up. Like people did with the Ro80's.

[James Doulton]

How does that compare with the 6 speed fitted to some MX5's? Was that the RX8 one again? There is one on ebay for £250 whereas the 5 speeders are more like £30.

What is the output fixing like? Any chance that an Escort prop would fit?

[Big Vern]

Basically the same box though some ratios in later boxes are different also check out what rear end ratio is used as some only quote the overall ratio.

1.8 Zetec friction disk slides straight onto the 6 speed first motion shaft but the first motion shaft nose that goes into the back of the crank is too short to work with the Ford without an adapter. Shame as the Pinto crank/flywheel bolt pattern is almost the same as the early MX5 :(

Not sure on the output shaft.

[James Doulton]

If we are worried about emissions then probably we'd need to go over to fuel injection. I don't see why a good condition crossflow or Pinto shouldn't be as good as a modern engine, given the right engine management. Obviously a modern 16v engine is a better choice for power, but efficiency? I don't see why that should be different.

If we want to be truly modern then we'd need to go for a small engine and add a turbo. So take a 1300 crossflow and put a turbo on it along with intercooler and multi-point fuel injection. With a high torque cam and a bit of porting then that should be good for 130bhp and it wouldn't upset the car's balance like some of the other options would.

[Steve Kerswell]

That is a really good thread Graham, I am now on turbosport :-)) (thinking outside the box :-))) ) its a play on words !!

So on to back axle/ diff etc. any suggestions ??? Borderline IVA territory, 

[Adrian Southgate]

Steve, you have four (or six) perfectly good mounting points on which to construct a subframe which would not need an IVA. Its not going to intrude into the car unless you drop it into the weeds so its all down to width really. Any caged IRS 'could' be used if you can get it narrowed to fit. How much BHP you throw at it? well from a pinto its not going to be over 200 so what about a narrowed Sierra 4x4 IRS with LSD 

[James Doulton]

One little point, reading that thread, the RX8 has a hydraulic clutch so that is a little issue to sort.