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Rx8 1.8t 20v conversion for track
john-t5 - 29/2/16 at 02:22 PM

Don't know if this will intrest you guys. But I've started to put a 20v turbo in an rx8, the help I've received from rubjonny & toyotec, has been invaluable & convinced me to join the club.

I'll start by copying the first few posts from another forum to get us upto date.
I've decided that I'm going to do an engine swap in my track car project. More out of curiosity than anything else.
I've seen a few projects done, but with no real world feedback.

Here's some of the things I'll try show.
•REAL & FULL cost of conversion.
•Time actually spent working on car.
•How car compares once finished (if finished) have my other RX8 to compare it with.
•Cost of any engine modifications. (Again if finished)

I'll keep editing this first post with costs & times.

COSTS.
•RX8 £200
•Transporting RX8 £90
• Audi engine, loom, ecu & gearbox(will be sold on) £200
• 2 sheets of cardboard for adapter plate £4
• sheet of MDF (mock up adapter plate) £10.38
• steal plate for adapter £26.38
• taper bit for adapter plate £10.99

Total so far = £541.75

TIME.
•Removing engine & box from Audi 1:15 (was just over an hour, will round things up to the nearest 15 mins)
• Remove engine from RX8 2.30 (lots of swearing involved [-X )
• Sit block in place & take some measurements, experiment with what clutch could work. (Time including picking up parts 2.30
• draw up adapter plate on cardboard 0.45
• center engine in the bay & start to cut the bulkhead. 2.00
• Remove dash & air con unit. Was a pain, but now I've done it I recon I could do it in have the time now. 3.30
• Cut some more from bulkhead. 1.00
• Cut even more from bulkhead to get inlet, cam cover & exhaust manifold on. 4.15
• bulkhead made 5.15
• passengers side engine mount made 4.30
• adapter plate 3.30
• drivers side engine mount 3.30
• loom work so far 4.15
• remove bumper & radiator 2.30

TOTAL TIME SO FAR. = 41.15


If you can think of anything else, just post up & I'll add it on.
I have no time limit on this, but will do my best not to let it drag on forever. Finishing off a xr2 turbo track car for a friend over the next week then this is top of the list. :wink:

Engine I will be using is the VAG 1.8 20v turbo, not my first choice of engine. Cheap & plenty available. Massive market for tuning & one of the main reasons was, easy to use standard ecu.

This is the RX8 I bought with low compression for £200



Got the car dropped off to remove the engine from.








I'll do my best to answer any questions as I go. :wink:

Cheers John

[Edited on 29/2/16 by john-t5]


john-t5 - 29/2/16 at 02:29 PM

Finally got the xr2 I was restoring & convering to a turbo finished & MOT'd last month.







So after taking a few weeks off the REX has finally made it into the garage.

Cheers John


john-t5 - 29/2/16 at 02:31 PM

Removed the engine. Lots of seized & snapped bolts, as the car has been lying by the sea in Wick for 2 years before I bought her. #-o











Now the hard work starts. Collect a loan of a mockup block later this week.

Cheers John


john-t5 - 29/2/16 at 02:33 PM

Well picked up a lone of a scrap block for mock up, so stuck it in to take a few measurements.


Also got donated a few old flywheels & clutches to have a play with. Have found a mix that might work. 1.9 tdi a4 solid flywheel (if I can find one at a reasonable price) with a 4x4 Sierra Cosworth friction plate & Audi pressure plate. Fly would need a lip machined on it to take the rx8 starter ring gear. Or get a custom fly made to take rx8 clutch. Once adapter plate arrives I can take final measurements & make a decision.
So most of my time has been spent like this. :roll:


Another 2 1/2 hours spent. Including picking up parts donated.

Cheers John


john-t5 - 29/2/16 at 02:34 PM

Broke out the CAD (cardboard aided design) to make a start on a mock up adapter plate. First plate will be made out of wood, just to check fitment & I can take all measurements from that. Saves money on wasted steal if it's not right. [-o<



Cheers John


john-t5 - 29/2/16 at 02:35 PM

Offered the wooden mock up adapter up to the VW engine. So far so good. Just need to see if it fits both together. [-o<



Cheers John


john-t5 - 29/2/16 at 02:36 PM

Engine & box bolted together using mock up adapter plate. Time to get engine mounts made, then make room for the head. #-o



Cheers John


john-t5 - 29/2/16 at 02:37 PM

Spent some time, got the engine centred & at the proper hight in the bay. All measurements taken from gearbox on my rotary powered rx.


Sat the head on to see how much I'll need to cut the bulkhead. :shock:


Some more clearance required, could just use a bigger gearbox adapter, but want engine as far back as possible.


Cheers John


john-t5 - 29/2/16 at 02:39 PM

Unfortunately I didn't manage to make the road trip this weekend. :roll: But did put some time to good use.

Dash looked so nice at the start of the day.


But it had to go.






Gave me the acess to cut the bulkhead so I could get the engine as far back as I want. Still lots of clearance needed & then work out how I get a heater back in her. :-k


Cheers John


john-t5 - 29/2/16 at 02:42 PM

Most of the engine physical in the bay today. Lots had to come out the bulkhead. Need to put a bit of strength back into it next.


Inlet on.


Exhaust manifold on. This isn't the one I'll be using. Proper one I have has the turbo further forward.


View from inside the car. Might not need fancy gauges. Passenger could just lean forward & feel intake & exhaust temps.




Bonnet even fits.


Cheers John


john-t5 - 29/2/16 at 02:43 PM

Didn't get a chance to work on the car today. But sat the strutbrace back on, just to show how far back the engine is sitting.


Could even put the standard cover back on. :wink:


Cheers John


john-t5 - 29/2/16 at 02:44 PM

Sorry guys not had much time to spend on the car. But managed to get some time during the week to make the adapter plate.


Made the new bulkhead this weekend. Have left a removable inspection plate, to allow access to the rear of the engine.


Should be enough room for the engine now.


Plan of action for this week is to get engine back in with proper plate, make engine mounts & take final measurments for flywheel.

Hope to keep this post moving & updated now.

Will update time spent ASAP.

Cheers John


john-t5 - 29/2/16 at 02:45 PM

Passengers side engine mount tacked up.


All welded up.


Cheers John


john-t5 - 29/2/16 at 02:45 PM

Got the drivers side mount tacked up.


All welded up.


Mock up engine in, sitting on its own mounts. Still have proper spacers to make to replace washers.




What do you think so far guys?

Cheers John


john-t5 - 29/2/16 at 02:46 PM

Made a start in the loom last night. Note to self, if someone who knows, tells you to try & avoid a loom from a Passat or A4. Next time listen. Most of loom is invaded in a foam/tar, that has to be removed. #-o

Started like this


Got it this far before I needed a break, it really is a nightmare.


Everyone in work thinks I'm mad, sitting doing this on my teabreaks.

Cheers John


john-t5 - 29/2/16 at 02:47 PM

Well the plan for this week, while I'm waiting on parts. Is to get this cleaned up & ready to put in for the first of many times this weekend.


Cheers John


marc_cowley - 29/2/16 at 02:51 PM

Following.


Chaz - 29/2/16 at 04:30 PM

Ambitious AND I'm following!


Benzine - 29/2/16 at 05:42 PM

Decent


big_wasa - 29/2/16 at 06:24 PM

Look forward to progress


maccmike - 29/2/16 at 06:59 PM

Keep up the good work


dinosaurjuice - 1/3/16 at 08:45 AM

Really like the RX8, and even more so the concept of swapping the engine for a tried and trusted VW turbo lump. Following


john-t5 - 1/3/16 at 09:35 AM

Got the engine decluttered a bit for fitting in. Also cleaned up a bit too.


Also cut down the front pulley & mounted the RX8 trigger wheel. This is needed to send a signal to the RX8 ECU & should make the Rev counter, power steering & ABS work.
Original pulley


Cut aircon belt drive off


Got a stroke of luck to centre it. When I put bolts through the original mounting holes, they are a tight fit into the centre of the VW pulley. There for centering the trigger wheel. :thumbup:


All done.




Cheers John


john-t5 - 6/3/16 at 01:03 AM

First part ordered turned up today, can't wait for the rest so I can get engine in.



Cheers John


john-t5 - 7/3/16 at 09:38 PM

Manifold turned up today, just a cheap eBay one at the moment. Will be upgraded, if conversion turns out to be worth it.


Looks a tighter fit than it is. Engine has to go back over to the right & dropped down a bit. Have the engine mounts back off to do a small mod. Will make a heat shield to protect brake & clutch master cylinders.


Just flywheel to come, then I can put proper engine in & start the hard work of piping & wiring.

Cheers John


john-t5 - 8/3/16 at 08:38 AM

Love it when I get to play with big boy toys. Got the plasma cutter out to make stronger plates for the engine mounts. Using what's left of the steel from the adapter plate.






Should be strong enough this time. 10mm steel. Will update times & costs tonight.

Cheers John


john-t5 - 9/3/16 at 11:33 PM

Re did the engine mounts.

First go just didn't look strong enough


Looks a bit better now.


Also fitted the RX8 alternator to the Audi engine bracket. Using the RX8 starter & charging loom.


Cheers John


john-t5 - 14/3/16 at 06:19 PM

Car looks like it's went backwards this weekend. But got engine bang centre in the bay & holes drilled in subframe for the engine mounts.

Before removing the mockup engine hopefully for the last time.


Bay looks very empty now. Also cut out the support for the battery, I'll make a new one as coolant pipe has to change direction & be mounted higher.


Oil coolers & pipework also removed, for the moment anyway.

Cheers John


john-t5 - 16/3/16 at 09:41 AM

Modified flywheel turned up today, so I'll need to get it all cleaned up & fitted to proper engine.




Hope to have a go at fitting engine this weekend now. Possibly firing it soon. WISH ME LUCK


Cheers John


john-t5 - 20/3/16 at 10:28 PM

The proper engine has made it into the garage now. Flywheel & clutch fitted, almost ready for the big lift tomorrow.




Think I'll have to clean the breathers out first.


Cheers John


john-t5 - 21/3/16 at 10:52 PM

Engine is finally in. What a nightmare that turned out to be. Had never put the engine in complete before & had never put sump on mockup engine. What a mistake that was. Lots of small jobs done I wasn't looking forward to due to my error. Subframe bolts freed off, steering rack bolts freed off & anti-roll bar freed off.


Had to make a small bit of clearance on the subframe for the sump, but just glad to see it in.


Now the fun starts, wiring & piping it up next.

Will need to update times. Have them all wrote down in the garage.

Cheers John


john-t5 - 1/4/16 at 02:08 AM

Started to get some of the pipe work sorted. I thought I start with the metal pipes on the engine. Started with the Passat top pipe.


Was going to interfere with the manifold I'm using.


With a simple bit of cutting & welding, it's sorted. I hope.


I've also made to bottom pipe fit my application, but forgot to take pics.

Times also updated on the first page.

Cheers John


obr_technology - 1/4/16 at 10:29 PM

Really enjoying following this, keep up the good work!


coozer - 2/4/16 at 04:21 PM

When you made the adapter plate how did you make sure the gearbox input shaft was centre in the crank/flywheel and how did you compensate for the distance the gearbox shaft is moved away from the engine??

Looking good by the way,
Steve


john-t5 - 16/4/16 at 07:47 PM

Done everything from the same centre point when marking out the pitch/diameter of the holes. After testing, I'll get a cad program made up & get a proper plate cut.

Got a bit lucky with the input shaft, the crank of the VAG engine sticks out from the block about the same distance as the adapter, on the rx8 it's just about flush.

Cheers John


john-t5 - 16/4/16 at 07:48 PM

Not had much time to work on the car the last couple of weeks. Been busy getting the retired track car out of hibernation & ready for a rolling road day. Back on it over the next week.

The car the rx8 is replacing on track.
https://youtu.be/KWgQgnfxDyI

Cheers John


john-t5 - 18/4/16 at 11:48 PM

Fitted the starter today & checked that it would still engage with the modified flywheel. Was chuffed to hear it turn over.

http://youtu.be/wJYVPrcnsd4

Cheers John


obr_technology - 19/4/16 at 05:34 AM

quote:
Originally posted by john-t5
Fitted the starter today & checked that it would still engage with the modified flywheel. Was chuffed to hear it turn over.

http://youtu.be/wJYVPrcnsd4

Cheers John


Glad it's progressing well.

Could you tell me if the starter motor is on the bell housing side of the flywheel? If so that would be ideal for my project as the type 9 bell housings all have the starter on the engine side of the flywheel (from what I can see).

[Edited on 19/4/16 by obr_technology]


john-t5 - 19/4/16 at 07:56 AM

Rx8 starter is on the bellhousing side.

Cheers John


obr_technology - 19/4/16 at 09:13 AM

quote:
Originally posted by john-t5
Rx8 starter is on the bellhousing side.

Cheers John


Great, thank you.


nick205 - 19/4/16 at 03:01 PM

Must admit this is quite interesting to watch. Given the low cost of an RX8 with a spanked rotary engine and the availability for VAG engines it's quite a tempting proposition to do.


john-t5 - 24/4/16 at 10:22 PM

A few small jobs done today.

Blanking plate fitted to the rear of the head.


Wiring all connected to the engine, think I'll be able to fit it nice & tidy with minimum work.




Piped most of the turbo up temporarily, with the pipes I have about. Just so I can try & test fire it before going any further.


Plan is to pipe up the rest of the intake side of things, try & test fire it for next weekend if I get time & get ECU back. Getting a bit nervous now. If you can spot anything fitted wrong please let me know.

Cheers John


obr_technology - 7/5/16 at 07:29 PM

Hi John,

Any progress on the rx8? Can't wait to see it running!

Cheers

Olly


john-t5 - 8/5/16 at 07:28 AM

It's all temporally wired & piped up. I'm just waiting on my ECU coming back from immobiliser delete to test fire the engine & test the clutch before I go any further.

Cheers John


marc_cowley - 8/5/16 at 08:47 AM

also looking forward to this! Who is doing you immob delete? Can they do al Marques or is it just bag? Thanks


john-t5 - 9/5/16 at 09:21 PM

It's just VAG the guy does. But if it's not done this week I'll be picking it back up. Has had it over a month.

Thought I'd already added this video on here.

Modified fly wheel fitted, starter engages & turns engine over.

http://youtu.be/wJYVPrcnsd4

Cheers John


obr_technology - 9/5/16 at 09:38 PM

Looking good.

Are you running the VAG ECU to run the engine and the Mazda ECU and sensors so the dash still works?


john-t5 - 10/5/16 at 11:25 PM

That's the plan. Have the trigger wheel mounted to the front of the VAG crank, still to mount the pickup. This should give me the signal to the ECU for the Rev counter, power steering & ABS. Then the VAG ECU will be left to run the engine. Only thing I haven't really looked at so far is the traction control. Not a big deal on this. Will just be a track car. But would like it on a road car. I'd need to figure out a way to get the RX8 ECU to talk to the VAG throttle. But that's a thing to play with in the future. Unless anyone has any ideas?

Cheers John


john-t5 - 7/6/16 at 10:58 PM

Unfortunately not really much to report at the moment. I'm still waiting on my ECU coming back. :-k

Just thought I'd post to let you's know the project is still ongoing.

Have spent some of my time helping some friends compete at knockhill. Which lets me play with some interesting cars.






Also a few mods to the fiesta that we built last year. Arches rolled to get bigger wheels on to allow for a brake conversion


Did get a couple of jobs done to the rx8. Drilled & tapped the rear of the head to take an outlet that suits my application.




Messed about with the water pipes a bit till I was totally happy with them. Will update times ASAP.

Almost forgot, got some tail pipes FOC for me to start making the exhaust. Should be big enough. :lol:




Cheers John


john-t5 - 14/6/16 at 05:19 AM

Got my ECU back at the weekend & got the car fired. Started no problems, even with half the pipework missing.

https://youtu.be/W330j7BkKS4

Cheers John


obr_technology - 14/6/16 at 07:16 AM

Great stuff, nice to see the project progressing John.


john-t5 - 19/6/16 at 08:26 PM

Ordered some parts to make the the breather system.






Hope to get a full day working on the car tomorrow

Cheers John


john-t5 - 3/11/16 at 05:02 AM

Turbo coolant feed pipe made.


Bottom radiator pipe made.


Top radiator pipe made.


Cheers John


john-t5 - 3/11/16 at 05:03 AM

Been a while since I've been able to work on the car. But finally got the intercooler in a position I'm happy with. Had to remove the front crash bar, I'll make a different one up. Didn't realise the intercooler was this big.








Cheers John


john-t5 - 3/11/16 at 05:03 AM

Started to mock up the boost pipes. Even made my own bead roller of sorts. Should do the job.


First boost pipe just about mocked up.



Cheers John


john-t5 - 3/11/16 at 05:04 AM

Got one of the boost pipes done. Quite happy with it for a first attempt.




Have to make an exhaust manifold now. Lesson learned about buying a cheap eBay one.
ops: #-o

Cheers John


john-t5 - 3/11/16 at 05:05 AM

New Exhaust manifold here. Some assembly required.


Could be a while before it gets done. :cry:


Find out on Thursday if it's broken or not.

Cheers John


john-t5 - 3/11/16 at 05:05 AM

Started to mess about & mock up the exhaust manifold tonight. No off the shelf manifold will fit, due to how far I'm into the bulkhead. #-o


I'll need to sit & update first post with times, still start the stopwatch when I go into the garage. Just keep forgetting to lift notepad to update the time & don't want to guess at it, or lie about time. :^o

Cheers John


john-t5 - 3/11/16 at 05:06 AM

Thankfully the ankle is all healed up now & I can finally get on with the car. I've not been sitting about doing nothing though.

Last month I got the chance of being part of the pit crew for a super tourer at the super tourers race at knockhill & also part of the crew for the ultima again. To say I was chuffed is an understatement, even although I was still hobbling about.








Unfortunately one of the BMW cup cars I help with had a small bump & any spare time has been spent repairing that. But worth it finished today & back ready to race this weekend.



This is the last race of the year, so more time to get the RX8 done.



Cheers John


john-t5 - 3/11/16 at 05:07 AM

Managed to get a few bits done. Brackets made for the breather & ABS block. Both fitted. Just waiting on 2 ends to finish the breather pipes. But I'll get the brake pipes done while I wait.



Cheers John


john-t5 - 3/11/16 at 05:07 AM

Been a bit distracted from the project again, missed track too much. So dragged the 3 door out & got it ready for a bit of a play last weekend the weekend



Finally got the manifold made up, let's hope it works. On to making the intake pipe & boost pipe up. Ends for breathers here too, so let's hope for big progress this week.


john-t5 - 3/11/16 at 05:09 AM

Sorry I hadn't posted for a while guys. But have copied over some updates. This is where I stand at the moment. Slow progress, but it's still progress.

Cheers John


obr_technology - 4/11/16 at 11:04 PM

Glad to see you are making progress John, sounds like you are suffering for mounting the engine so far back into the bulkhead. I'm sure the end gains will be worth the hassle!


john-t5 - 11/12/16 at 04:11 PM

Got some time at last to finish the inlet side boost pipe (almost forgot to mount the map sensor) & start mocking up the turbo side pipe.








Not to sure about it at the moment, would like the turbo outlet a bit shorter.

Cheers John


Toprivetguns - 11/12/16 at 06:37 PM

Very keen to see this RX8 up and running. A friend has just started a similar project with an Audi V8.

Keep us posted !


john-t5 - 14/12/16 at 04:09 AM

Now that sounds interesting. I hope he does a build thread I can follow.

Cheers John


CosKev3 - 14/12/16 at 07:28 AM

Cut the outlet off the turbo and weld it back on facing forwards would be my suggestion

Done it with the GTB2260 on my daily driver and it does not effect performance.


PAUL FISHER - 14/12/16 at 12:23 PM

What ECU are you using for this conversion.


john-t5 - 15/12/16 at 03:19 AM

That's what I'm looking at doing, cutting & modifying the outlet pipe. I'll need to get it sitting were I want it. Turbo has been a bit of a pain.

I'm running the standard VAG ECU bosh me7.5 to run the engine & the rx8 ECU to run the dash & the rest of the car.

Cheers John


john-t5 - 5/1/17 at 03:41 PM

Well turbo outlet cut & away to get welded. So I thought I'd move on with another job.

Need some connections from the rx8 engine loom to power the dash, ABS & steering. Also the revers light & neutral switch wiring is in here. Info on this is not as readily available, like the VW stuff.


Also have the starter & charging loom to sort to work with the rx8 starter & VW alternator. Then get it all in the bay along with the VW loom & looking neat.


john-t5 - 14/1/17 at 12:41 AM

Modified the RX8 engine loom for the sensors I need to power the dash, steering & ABS.

Before


After


Also got the turbo back. Bit better looking now.




Cheers John


john-t5 - 17/1/17 at 03:38 AM

Both looms in & wired. Car now starts from the rx8 key, dash working. Need to tidy it all up to look nice now. Well chuffed.

Still lots to do intake still to finish, accelerator pedal to modify, fuel system to finish. But a least there is a bit of progress.

Cheers John


Toprivetguns - 17/1/17 at 10:17 AM

Good work so far!


john-t5 - 18/1/17 at 12:42 AM

Thanks, taking a lot longer than I had planned, but just can get the time I want to spend on it. Target is track use this year.

Adapter made to run the rx8 coolant temp sensor. For the dash & to run the cooling fans.


Passat pedal modified to fit the pedal exactly in the same place as the RX8 one. Also made a new plate to mount the rx8 pedal plate, so it looks the same as the rest.


Cheers John


Gre3D - 10/2/17 at 11:02 PM

wow,
lots of work went into this project allready!
i'm curious to seeing it run, should make a fast car!


Nojjer - 17/2/17 at 09:11 AM

wow this is a brilliant project! i assume you have used stock rx8 box, flywheel and clutch?


marc_cowley - 16/5/17 at 01:56 PM

any updates?


Shiggins92 - 23/6/17 at 09:33 PM

Oh wow well this is interesting!!

I have a golf mk2 running a 20vt and its great fun haha

Had great fun with an RX8 on track not long ago what was running a v6.

Any updates?


john-t5 - 28/6/17 at 05:26 AM

That sounds interesting, what engine was it running. Any pics or info.

Finally managed to get back on to this.
Drivers side boost pipe finished & fitted.




Cheers John


john-t5 - 28/6/17 at 05:28 AM

It's running stock 6 speed gearbox, clutch & a modified RX8 flywheel to fit the VW engine

Cheers John


john-t5 - 8/9/17 at 10:50 PM

I'll need to update this & change the links from Photobucket

Cheers John