Board logo

Engine Choice... Enter RX8
scootz - 6/12/13 at 12:26 PM

Aaaaargh... why can't I just be normal!?

Where I'm at...

I have a Quantum Xtreme in my garage with a good Type 9, but it needs an engine.

I have two perfectly good options sat next to the car - the first is a freshly rebuild, good-as-new XE with alloy belhousing to suit. Will need to fabricate mounts, get clutch / flywheel, injectors, exhaust, ECU to suit and dyno time, so still a bit of money to be spent on that option. Option 2 is a low mileage 2005 MX5 engine with 5-speed box. Would need pretty much the same as the XE, less the clutch / flywheel, but plus a prop.

So why the hell am I itching to fit an RX8 lump and 6-speed box???

I know these engines are notoriously fragile, but I envision buying a reasonable running lump, and a non-runner for pulling apart, learning from and hopefuly rebuilding. The plan would be to work on the non-runner and then swap them over as and when required. And repeat if necessary...

The sale of my other bits would more than cover the cost of the RX8 bits (including spare) and put a wee bit in my pocket for starting collecting engine rebuild parts. The costs to get it running would be in-line with either of the XE or MX5 options (mounts, ECU, exhaust, ECU, dyno time)... possibly a little less though as I wouldn't be fiddling with the RX8 inlet, so could sell my 45's and put the cash towards the costs.

I also know that the MPG is poor at 20-ish, but it's a toy car... and I'm worth it!

The way I see it is that the RX8 components can be got cheap (for obvious reasons), the drivetrain is almost 50 kgs lighter than the XE's, it almost revs like a BEC, spits out 230 bhp, and the 6-speed box is a pearler. And above all else, it's a wee bit different

It's that last bit that gets me into trouble so often though... the urge to do something completely (or in this case slightly ) left-field.

Stupid direction... and if so, someone please talk some sense into me!

[Edited on 6/12/13 by scootz]


mcerd1 - 6/12/13 at 12:31 PM

so what happened to this being the car you'd actually drive ?

just stick the XE in it - its not like you've not got other projects


[Edited on 6/12/2013 by mcerd1]


femster87 - 6/12/13 at 12:44 PM

Just sat here laughing. You are just like me Scotty ( alright since your the older one am just like you) I started to fix exhaust on my smart roadster today and decided I will carry on stripping it for a new engine. Just small problem of finding a replacement over the weekend.

I must say you do make me laugh though. I have also lost hope with the carbon tub project. Any takers??


Wheels244 - 6/12/13 at 12:45 PM

Sell the XE to me for a spare and stick a rebuilt RX8 in


Jon Ison - 6/12/13 at 12:47 PM

Why do we need to talk sense into you, your talking sense already, in your position I too would go the RX8 route, I have said for years now next build rotary engine practical or not, that's what I want, this goes back to my autograss days running a Mazda turbo nutter rotary in the rear end of a special.

Do it.


r1_pete - 6/12/13 at 12:48 PM

I do fancy putting a conventional engine in an RX8, maybe we could split a car between us


scootz - 6/12/13 at 12:56 PM



Some interesting reading there! Keep it coming!


zilspeed - 6/12/13 at 12:57 PM

Scott

Look up Peter Locke on FB.

He's local and has run an RX8 in sprints and hills for years.

He's also very knowledgeable about the Mazda rotary.


scootz - 6/12/13 at 12:58 PM

Cheers Zil.

The more I think about it, the more that an RX8 seems reasonably sensible. Certainly mo less sensible than a car with a bike engine in it.


scootz - 6/12/13 at 01:00 PM

The Xe... if anyones interested!




FuryRebuild - 6/12/13 at 01:13 PM

+1; we don't do this because other people see sense in different ways

quote:
Originally posted by Jon Ison
Why do we need to talk sense into you, your talking sense already, in your position I too would go the RX8 route, I have said for years now next build rotary engine practical or not, that's what I want, this goes back to my autograss days running a Mazda turbo nutter rotary in the rear end of a special.

Do it.


pewe - 6/12/13 at 01:43 PM

There was an RX engined Se7en at Motorsport Events track-day at Keevil on Nov.16th.
IIRC reg was Q ... EAN or similar as it's close to my F27's reg.
Current owner hadn't built it but he reckoned it was exciting to drive and it sounded fricking awesome.
Maybe worth trawling through Faceache or youtube for pics?
HTH.
Cheers, Pewe10


tomprescott - 6/12/13 at 02:39 PM

Go for the rx8, they seem to be going for peanuts at the moment and you could probably sell the rest of a complete car to get the engine and box for free.

I must admit that the Wankel story is a good one, described as an aloof engineer who considered himself the third in a line of automotive legends (the other two being Otto and Diesel)! That said, the wankel engine looks like a great option for a kit, almost into BEC territory with regards to being light and revvy but without the headaches of expensive gearboxes and reversing gubbins.


The Black Flash - 6/12/13 at 02:45 PM

The rotary has always seemed like a very sensible choice for a lightweight fun car to me. Do it


waggy - 6/12/13 at 02:54 PM

Don't do it!!! An rx-8 engine won't work at all well in a 7.
There are massive hurdles to overcome, not least the fact that when you think all is going well you blow up your engine for not having enough back pressure in the exhaust!
Do a little search on rx-8 in a seven and you'll find several threads where it's been done..... And then undone!

I'm not trying to say you can't do it, just ensure you are armed with all the information before you sell what looks like a well prepared, well suited engine.


mookaloid - 6/12/13 at 02:58 PM

You could buy my spare Saab 2.3 Turbo engine off me and use that


sdh2903 - 6/12/13 at 03:01 PM

Fit the XE, it looks lovely.


waggy - 6/12/13 at 03:02 PM

quote:
Originally posted by tomprescott
Go for the rx8, they seem to be going for peanuts at the moment and you could probably sell the rest of a complete car to get the engine and box for free.

I must admit that the Wankel story is a good one, described as an aloof engineer who considered himself the third in a line of automotive legends (the other two being Otto and Diesel)! That said, the wankel engine looks like a great option for a kit, almost into BEC territory with regards to being light and revvy but without the headaches of expensive gearboxes and reversing gubbins.


If you buy an rx-8 to remove the engine and box you will be left with a virtually worthless lawn ornament! The engines are the only thing on these cars that break!! If he does decide to go down this route and put the Rex engine in the best thing to do would be source a loom elsewhere and retro fit some other engine into the rx-8! With a Nissan engine fitted they are a much more drivable, user friendly vehicle.

Despite the fact I don't think it'll work in a 7 for various reasons, all the flooding and starting issues would put me off.

Ps. All this info is coming from me...... an rx-8 owner!!!!


waggy - 6/12/13 at 03:07 PM

Here is a thread to have a read at before you start.

http://forum.wscc.co.uk/forum/index.php/topic/101235-need-a-valuation-on-my-se/


Jon Ison - 6/12/13 at 03:41 PM

quote:
Originally posted by waggy
Don't do it!!! An rx-8 engine won't work at all well in a 7.
There are massive hurdles to overcome, not least the fact that when you think all is going well you blow up your engine for not having enough back pressure in the exhaust!
Do a little search on rx-8 in a seven and you'll find several threads where it's been done..... And then undone!

I'm not trying to say you can't do it, just ensure you are armed with all the information before you sell what looks like a well prepared, well suited engine.


That's what turbos are for.


Canada EH! - 6/12/13 at 04:12 PM

There was a RX 7 powered Locost here in Ontario running in Solo, nobody could beat him for two years in including Formula fords. The only way that stopped him was he sold the car.

My son has an RX 8 with 160,000 km and yes it has had a new engine supplied by Mazda at 130,000 km.

It does burn fuel, on a trip last summer with a friend driving a Corvette Z06 they both got about the same gas mileage.

I have driven his RX 8 and another for a few hundred miles as I picked them up new from dealers a long way away.

The real trick to RX 8 engine long life is to break them in slowly with much respect, nothing over 4000 rpm for 1000 km, this is very hard for most people when dealing with a performance car, the reason I was sent to get them and not two 20 somethings.

They also like a little 2 stroke oil in the gas once in awhile.


NigeEss - 6/12/13 at 04:27 PM

quote:
Originally posted by waggy
Don't do it!!! An rx-8 engine won't work at all well in a 7.
There are massive hurdles to overcome, not least the fact that when you think all is going well you blow up your engine for not having enough back pressure in the exhaust!
Do a little search on rx-8 in a seven and you'll find several threads where it's been done..... And then undone!

I'm not trying to say you can't do it, just ensure you are armed with all the information before you sell what looks like a well prepared, well suited engine.


Ah, the old "engines need back pressure" myth rears it's head again.


chrism - 6/12/13 at 04:59 PM

Arent they quite a wide engine aswell for a locost, due to them being quite a low block height the intake and exhaust both come out of the steering side of the engine quite low down compared to other engines and will probably get in the way of the steering column/extension so that will need rerouting if possible either further to the side or over the top.

[Edited on 6/12/13 by chrism]


rdodger - 6/12/13 at 05:31 PM

My vote is for RX8 because.....

231 BHP Standard
Light weight
6 speed box with decent ratios
Low centre of gravity
A rebuild is less than tuning another engine to over 200bhp
9000 rpm!
Awesome sound!

It appears RX8 engines start to fail at 60,000 mostly due to poor maintenance. ie not keeping an eye on the oil level.

So in the average kit the engine would last 20 years!
Most owners of a kit lift the bonnet every time they drive the car, 4 times on a track day! No problem with topping up the oil then.

Do it, then tell me how you did it


D Beddows - 6/12/13 at 08:03 PM

Why not? because you'll spend a load of money and never finish it as another amazing idea will come along before you do

That's actually not a reason not to do it btw - I've just seen you not finish soooooo many things that were a good idea


Canada EH! - 6/12/13 at 08:47 PM

No problems here with steering, LHD, engine is almost round and smaller than a Kent 1600.


Simon - 6/12/13 at 09:18 PM

quote:
Originally posted by waggy

If you buy an rx-8 to remove the engine and box you will be left with a virtually worthless lawn ornament!


Excellent! If someone could buy an RX8, and remove engine and box/prop and diff, I'll give you £100 for the rest - so long as you're within a reasonable distance (and what's left of the car is immaculate!), as I need something to chuck a diesel engine into

Cheers

ATB

Simon


sdh2903 - 7/12/13 at 01:07 AM

Scootz you've gone all quiet on your thoughts, you been away buying an RX8???


chrism - 7/12/13 at 02:29 AM

quote:
Originally posted by Canada EH!
No problems here with steering, LHD, engine is almost round and smaller than a Kent 1600.


Yeah but both the intake and exhuast appear to be on the RHD side, not ideal for the UK.


boosted - 7/12/13 at 12:01 PM

Copart salvage yard......07 plate rx8 231 with rear hit and only 28k on it went for 700 pounds. last week!

Got everything you need to do conversion.....make more like 210hp. But with straight headers and no cat will see big gains!

Ive got an SE with rx8 lump in it! The 1 mentioned above.....goes like snot. I dont know why it smoked for previous owner....i changed the exhaust as too loud. Had 5 secs of smoke when i added oil to the fuel tank before it mixed.

9200 rpms....need coils every 20k .

http://s1065.photobucket.com/user/boosted38/library/


scootz - 7/12/13 at 01:00 PM

quote:
Originally posted by sdh2903
Scootz you've gone all quiet on your thoughts, you been away buying an RX8???


That's because I've been busy at the auctions!

2004 6-speed with 50k miles. Reasonably local. £770 inclusive of auction charges and VAT. Couldn't even buy an engine for that on eBay!





XE for sale!!!


sdh2903 - 7/12/13 at 01:04 PM

We shouldn't be at all surprised but you don't half bloody work fast!!!

Wasn't central auctions in glasgow by any chance?


scootz - 7/12/13 at 01:44 PM

No. T'is in Aberdeen (so can nip in to see mother Scootz when I go to collect... which is nice!).


boosted - 7/12/13 at 02:25 PM

Spot on!

Change the coils as a matter of fact.....dont buy ebay 1's there fake.

www.mazdarotaryparts.com

Run premix 2 stroke oil in the fuel tank and should have no more apex seal wear.

might be worth having a read of the faqs on rx8club and mazdarotaryclub the latter i use extensively and a really friendly forum.

You can junk the air pump of the engine and rear 02 sensor but the front 1 is required to run the engine.

If you have any q's just ask!


scootz - 7/12/13 at 02:28 PM

Cheers!


Dualist - 7/12/13 at 04:42 PM

Excellent engine choice my friend, I'm fitting a 13b in my 7 and room won't be an issue, dropped it low as I'm going dry sump so loose about 3" in the height

Bargain price too, looks like another tool didn't know how to look after a rotary. There's a guy I know from school and he brought one for his missus and she just bimbles around in it, he brought it for £5k about two years ago and a dealer offered him £600 a month ago, lmfao.


femster87 - 7/12/13 at 05:27 PM

Nice one


ceebmoj - 7/12/13 at 06:09 PM

Please can you post up pictures and sizes of the engine and gear box once its out of the car?


boosted - 7/12/13 at 06:16 PM

quote:
Originally posted by pewe
There was an RX engined Se7en at Motorsport Events track-day at Keevil on Nov.16th.
IIRC reg was Q ... EAN or similar as it's close to my F27's reg.
Current owner hadn't built it but he reckoned it was exciting to drive and it sounded fricking awesome.
Maybe worth trawling through Faceache or youtube for pics?
HTH.
Cheers, Pewe10


HA HA that was me!


boosted - 7/12/13 at 06:18 PM

quote:
Originally posted by ceebmoj
Please can you post up pictures and sizes of the engine and gear box once its out of the car?



Tell me what you need as have an engine and box sat in garage...see my photos above.


ceebmoj - 7/12/13 at 07:19 PM

quote:
Originally posted by Dualist
Excellent engine choice my friend, I'm fitting a 13b in my 7 and room won't be an issue, dropped it low as I'm going dry sump so loose about 3" in the height



Do you have any more information on the dry sump set up?

quote:
Originally posted by boosted
quote:
Originally posted by ceebmoj
Please can you post up pictures and sizes of the engine and gear box once its out of the car?



Tell me what you need as have an engine and box sat in garage...see my photos above.


Some pictures of the engine and box together showing the rough size. I'm looking at a number of options at the moment.

[Edited on 7/12/13 by ceebmoj]


wylliezx9r - 7/12/13 at 08:55 PM

Please finish this project Scootz it sounds fascinating. Was going to do the same myself but opted for an S2000 motor in the end.

[Edited on 7/12/13 by wylliezx9r]


PhillipM - 8/12/13 at 01:43 AM

I've got a rebuilt RX8 engine sat right here waiting for a new home. Hell, I'll even throw in the long branch stainless exhaust manifold if you want it - we made 268bhp from it with that, a straight through exhaust and standalone.


Dualist - 8/12/13 at 10:27 AM

quote:
Originally posted by ceebmoj

Do you have any more information on the dry sump set up?

quote:


Here's my slow build thread mate...

http://www.haynes.co.uk/forums/showthread.php?t=8521&page=3

(if it asks for a password it's 'haynes', but I think they have sorted it out now).


ceebmoj - 8/12/13 at 01:53 PM

The build looks great and no password needed. It's an incredibly compact set up.


Dualist - 8/12/13 at 02:28 PM

quote:
Originally posted by ceebmoj
The build looks great and no password needed. It's an incredibly compact set up.


Cheers mate


Volvorsport - 8/12/13 at 03:45 PM

my mate geff at re:worx built a westfield rotary back in 1998 while we were at uni ... ive just realised that a long time now

personally id do a 12a turbo . no wiring to do , 2 inch su suck through carb - about 250 hp.


bill132hotrod - 8/12/13 at 05:10 PM

Is the XE still for sale pm me price please.


boosted - 11/12/13 at 04:44 PM

http://s1065.photobucket.com/user/boosted38/media/2013-12-09155547_zps0ecdf28b.jpg.html?sort=3&o=0

Couple of photos here of engine and box.... do you require measurements.....did have some but washed my hands!


boosted - 21/12/13 at 07:34 PM

[img]http://s1065.photobucket.com/user/boosted38/media/2013-12-21163513_zpsdcd6d8dc.jpg.html?sort=3&o=0[/img]

Pulled the standard engine today ready for the Hayward race to go in.