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It is a friends P100 pickup, which he got about 9 years ago, with a 2wd cosworth lump. unfortunately it had stood for a long time and the tinworms had a field day on the sills and footwells. We kind of knew it was a goner, so set about stripping it.
The shell is actually gone, we were hoping originally to reshell it, but were struggling to find anything in half decent nick for reasonable money. There were a few ideas throwing around as to what the engine was going to go back into, P100's were quite expensive and most of them being in their 20's were either nasty with rust or looked like a generally hard life. Sierra's were a similar story, and with us only having half an interior, and none of the cosworth rear suspension/diff/brakes it was going to be a pricey journey to having a sierra that would never really be a cossie.
After a lot of searching and reading other peoples builds on here and toying with ideas of RWD fiesta or focus projects, a random search for non runners on ebay brought up loads of Mazda RX8's mostly low mileage, with a hosed rotary engine.
These were looking more promising by the minute, much less cutting welding and headscratching than converting a front wheel drive motor,and the cossie clutch will slide straight onto the mazda gearbox
We ended up with an '06 black RX8 231 with 61k on the clock.
Its hard to believe how much (non working) car you can get for your money here, full heated leather, aircon, limited slip diff, carbon fibre propshaft, 6 speed box, all for Ł600!!
Hopefully Titch whose car it is will appear at some point and post some of the pictures he's got up too, as i think he took a lot more than me. but i did get a few in the engine bay as it was being stripped.
There are a few hurdles we're going to have to get over to make this work, The rotary is only a small engine, and sits fairly low and far back in the engine bay. We have a conversion plate to bolt the cossie block onto the mazda bellhousing, which will move the engine forward around 8mm, but the cylinder head and cam cover are still going to touch the bulkhead above the tunnel.
Did both the Saab and VAG conversions end up as runners in the end?
i read both threads before we got started with this, but they seemed to kind of end before the job was all done?
Did both the Saab and VAG conversions end up as runners in the end?
i read both threads before we got started with this, but they seemed to kind of end before the job was all done?
Hi mate, im the owner of the Saab'd RX8, I took over the build from the previous owner, i shall hopefully be taking it for an mot in the next few weeks. I was just looking at ebay this morning and seen that you now get a conversion plate for the RX8 gearbox to ford/vauxhall/etc , whats you plans for steering set up? you planning on get the mazda dash to work ??
Good news on the MOT then fjc, hopefully you will get through it ok. How do you think you will get on with emissions testing etc? Ive seen conflicting info about MOT emissions tests, some saying that if you declare the engine change you can take the test for engine fitted, and others saying you must fall within the specs for the car its fitted in.
We are hoping to keep the mazda steering rack and instrument cluster, using the RX8's ECU and wiring loom plugged into the trigger wheel sensor, temperature sensor oil pressure switch etc to fool it into thinking that it still has a mazda engine in there, which should make the steering rack power up and all the guages work properly. I'm pretty sure emissions and check engine light will go crazy, but if all the main functions are there i'll happily desolder a couple of led's. There are also a couple of companies out there that make a Canbus converter that you can connect inputs for temp, rpm etc and they program it to send the correct signals to the guage cluster.
Had a day or two at it again...
We had already had a few quick swings in and out with the engine to eye up how much mazda we were going to show the sacrificial grinder to, so the first bit to go was this crossmember. It previously had the battery and a HUGE airfilter box mounted on it, and looks like it was made with the purpose of giving them a solid place to sit rather than to strengthen anything up too much, although it will either be going back where it is, or moved forwards if needed.
De-crosmembered for a look at how its all going to get to the right spot. also had to remove abs pump and later all of the pipework will need to be rerouted
Titch demonstrating his best attempt not to look like a d**k
Next bit to go was the dash, we already knew we would need to cut into the bulkhead and tunnel, it was more a question of getting the input shaft into the clutch and working out how wide and far back to cut.
Not really been looking forward to this job, normally whenever i try to take apart interior trim, theres all sorts of cracking and crunching noises, and little clips snapping off, but this wasnt bad at all.
This is where you realise that a job is getting serious, when it begins to escape from the garage and begin encroaching on your already junk-strewn spare room
Craig at Dyno Torque has chucked a few LS's into RX8's and rear turbo'd two of them.
RX8's are really nice cars shame they came with the Rotary Wanker engine.
The YB conversion should be fun too
Whilst there was never going to be an easier time i took out the electronic throttle pedal to see what could be done to convert it to pull a cable, i still had the sierra/p100 pedal in with the pile of p100 bits, and would have bolted in fairly easy, but it wouldnt have looked right next to the other pedals and wouldnt have been at the perfect height like the original.
After taking the pedal apart i got the strongest bit of bar i could find, which actually happened to be a shaft off an old (and obviously hardcore) screwdriver and welded the little ball for the cable on. i then did a bit of measuring and trial and error and found out how far it needs to poke out in order to pull the cable the right distance.
i then drilled down the centre of the pedal just in front of the pivot so that the rod could be forced tight into it.
it feels a little springy with the bar being so long, so i will be slipping a 10mm OD aluminium tube over the shaft and then filling the void between them with epoxy, then epoxying both of them into the pedal, any luck that should make everything work much more solidly
then cut away the bulkhead and had another look at where everythings gonna go, it is a tight fit, and the steering rack is going to have to move slightly down from where it is, or the front edge of the sump may need a little trimming off and plating over, we're still a little undecided as to how it might affect handling, or if it will cause any bump steer by moving it down an inch, and i haven't looked into whether or not the sump has any space to give us yet.
engine mounts initially seemed to be in a good place for some simple mountings to be welded to the subframe
until.....
drivers side mount on a direct collision course with the steering column
Nothing a session with a welder and some steel wont fix, but for a moment there we thought we'd got an easy win on that one
Next job now is to sort the adapter plate between the engine and bellhousing as the one we have is putting a very slight tilt on the gearbox which is going to make it very difficult to mount it all back to the frame under the tunnel properly. once we have all these back together solid and aligned we can tell for definate what is going where, and how much room there will be for the steering rack and anti roll bar at the front
that might be something to look into later on rich, the throttle body we took off that was huge in comparison to the cossie one! day by he's gradually talking himself into bigger intercoolers etc, so at some point i think there will be an ecu upgrade on the cards!
We already have an adapter plate, but are struggling to get around the problem of the tilt that its putting onto the gearbox, it wouldn't be a problem in most cars as its only around 5 degrees, and would just angle the gearstick towards the drivers seat, but the mazda box is bolted directly to the power plant frame, which is like a solid frame connecting the gearbox to the diff. Theres literally no movement whatsoever and its not looking like an easy job to make or alter it to take the tilt. the plate could be re-drilled without the tilt on it, but that would mean one of the bolts from the bellhousing would have to be threaded into the plate, rather than going straight through it which could weaken it slightly.
Nothing we hopefully wont sort one way or another
Last edited by frug; 01-04-2015 at 08:48 PM.
Reason: complete illiteracy
Are 2wd and 4wd cossie exhaust manifolds interchangeable? as our 2wd one sticks out a couple of inches too far and is getting in the way a little and the 4x4 one looks to stay much tighter in which might free up some room.
can anybody also identify this turbo please? ive just confused myself more trying to look it up
Good news on the MOT then fjc, hopefully you will get through it ok. How do you think you will get on with emissions testing etc? Ive seen conflicting info about MOT emissions tests, some saying that if you declare the engine change you can take the test for engine fitted, and others saying you must fall within the specs for the car its fitted in.
We are hoping to keep the mazda steering rack and instrument cluster, using the RX8's ECU and wiring loom plugged into the trigger wheel sensor, temperature sensor oil pressure switch etc to fool it into thinking that it still has a mazda engine in there, which should make the steering rack power up and all the guages work properly. I'm pretty sure emissions and check engine light will go crazy, but if all the main functions are there i'll happily desolder a couple of led's. There are also a couple of companies out there that make a Canbus converter that you can connect inputs for temp, rpm etc and they program it to send the correct signals to the guage cluster.
Not to fussed about emissions, all i know is it will be a pass!! As my engine sits further forward i removed the original steering rack, I fabricated a BMW E36 power rack to fit the RX8 and made up track rod ends to fit. I have removed my abs now as it was sitting right onto of the turbo area.. A guy up here in scotland had a 1jz RX8 and he managed to run a trigger wheel and get his instruments working aswell.
29-03-2015, 09:23 PM
RX8 Cosworth conversion
