rx8 engine rebuild

Engine height is a somewhat limiting factor for many conversions it seems.

I know Reyland were converting a car to use the VAG 1.8t lump, if it all went to plan they were considering offering the conversion as a regular offering to customers, rather than just a one off. Martin hadland did post a build thread on the Passionford website a while back...
 
There are DVD torrents. Send me a trust message if you're interested in doing the job yourself. It's all you need for knowledge of rebuilding these engines. I've rebuilt a twinturbo motor then took it straight to the nubring after using this dvd.
 
looking at these myself now,

ideally buy something with a knackered engine and sling something different into it.


seems the LS1 is a common conversion over in the states, but your not exactly falling over them in the local breakers yard


something like this could be an option for an easy 200 bhp conversion

http://www.ebay.co.uk/itm/st170-eng...itu=UCC&otn=5&ps=63&clkid=7873313017383284833

either that or an injected rover v8 would make a fine choice. but again thin on the ground for good ones and not exactly cheap either.

Really need to have a look under the bonnet for one and get an idea of how much room there is to play with. plenty of choices for engines for not a lot of money, many of which that would give more power better economy and superior reliability to the renesis.
bmw straight 6? and if your a mentalist get one of a diesel flavour just for the epic MPGZsssss and the torques.

buy a ropey 328 spend a few weeks transering everything over and swearing at the wiring looms hey presto you have a reliable and more powerful RX8
 
q6600 said:
Yes, it was Hurley. Now i don't know what to do 3500 is a lot of money...
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I'd write it off as a bad decision and get rid of it asap to be honest. But if you decide to get it repaired, i'd take it to Hurley Rotary.

I traded mine in as soon as the warranty ran out. Car was still running ok at the time but I knew from the compression test results that it wasn't going to last too much longer.

Lost 4K in 12 months on the damn thing :mad:
 
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Speaking of buying cheap RX8s and putting a replacement engine in, I wonder if a Lexus 1UZ V8 would fit in the engine bay. Reliable, cheap, plentiful and make an awesome, awesome noise. 250bhp as standard and relatively light as quad cam V8s go.

A grand on a RX8 with a broken engine, a grand on a 1UZ, W58 gearbox from a Supra and adapter plate leaving a £1k-£2k to fit. £4,000 for a V8 53 plate coupe doesn't sound too bad to me?

I sometimes really wish I had a workshop to play around in on the weekends :(
 
What actually goes wrong with these engines? Is it just the rotor tips wear away?

Surely they could've just designed the engine to make them easily accessible, and make it part of a 50k service to get them replaced or something? Or are there other components that wear..?
 
godinman said:
What actually goes wrong with these engines? Is it just the rotor tips wear away?

Surely they could've just designed the engine to make them easily accessible, and make it part of a 50k service to get them replaced or something? Or are there other components that wear..?
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Apex seals on the rotor tips wear out, leading to loss of compression. This is the case on most RX8's anyway.

Would certainly not be easy to make them accessible to change readily. The whole engine has to come apart.

They tried to reduce this problem by adding in an extra oil way to the rotor tips on the RX8 R3, but it is an inherant design flaw with the rotary engines.
 
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IvanDobskey said:
Apex seals on the rotor tips wear out, leading to loss of compression. This is the case on most RX8's anyway.

Would certainly not be easy to make them accessible to change readily. The whole engine has to come apart.
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Edit - Missed the second line! Ohkay, so mainly labour then I suppose.
 
godinman said:
Edit - Missed the second line! Ohkay, so mainly labour then I suppose.
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Ah, sorry, added in a couple of extra thoughts :)

Yeh, there's quite a lot of labour involved. A full rebuild involves stripping the engine right down and replacing the rotor tips and seals.

Rotary engines are also very prone to carbon build up in the rotor chambers.
 
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Just how difficult are these to rebuild I've built a few 4 pots in my time but never played with a rotary
 
Delta12 said:
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either that or an injected rover v8 would make a fine choice. but again thin on the ground for good ones and not exactly cheap either.
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Bleh, what a horrible idea :D

I don't know if there's enough room under the bonnet for a straight-six, they're usually quite long. May not clear the hood.

LS V8's fine though, seen a few with those. Make real good cars. Then again, you could just buy a Corvette, but obviously it'd be LHD.
 
This is the project thread with the 1.8T conversion...interesting read although I agree with Matt82 in that its not necessarily the engine I'd chose. Its cheap, readily available, and tunable, but I don't think it has the character or the ability to rev well that you'd really want in a car like the RX-8. Something powerful, revvy and naturally aspirated would suit it better IMHO...

http://passionford.com/forum/restor...a-rx8-project-with-20v-audi-turbo-engine.html

As for what engines would fit:

The original engine is about the height of a normal 4 pot with the head removed, so the trans tunnel/bulkhead wasn't designed to clear anything above that height and also the belhousing actually sits inside of the tunnel so you can see that although a spacer plate would bring everything forward its still not enough if the head has anything overhanging further than the block face. The Audi engine has 4" of stuff protruding I have reduced this to 2" with a bit of relocation. So in an ideal world the gearbox would need to be moved forwards...

Problemo No.2 The gearbox doesnt have a conventional mount and crossmember, it has a long steel 'power frame' that joins the diff to the gearbox so no box crossmember (it does have a carbon prop though ). The gear stick goes straight into the box so the box can't be moved forward as the dash is in the way.

Sitting the engine further back does have its advantages though, the original electric power steering rack can be retained as the Audi pulley clears it and the other bonus is the engine sits behind the centreline of the front wheels

So in short if you're considering this you need and engine that doesn't have more than 2" head protrusion at the rear or you need to change the box and make mounts for that and the rear diff.
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Basically theres no easy swap...! Subaru flat 4 is too wide, many engines will be too long..the LS1 V8 must be a very compact unit or its a very involved conversion to get it to fit!
 
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