MR2 or E30 325i

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Discussion

ICSD

Original Poster:

638 posts

235 months

Tuesday 11th November 2008
quotequote all
I'm looking at a new car for sprinting next season.

I was originally thinking Puma but I can't quite bring myself to have a front wheel drive car and also I'm worried about the Nikasil engines - especially as I'm only after a cheap one.

So I've decided it has to we RWD and I'd really like to be in the 1800 to 2600cc grouping.

I've nailed it down to two cars that fit the bill and are available at sensible money - MR2 or E30 325i and wondered what you chaps' opinions might be. Which is likely to be quicker, least hassle and cheapest to upgrade and fix?

Also, any other interesting suggestions about which car to use. I'm looking at an overall budget of £2k to include the car, insurance etc and the necessary upgrades. I'm not too worried about being fastest in class but I would like to be competitive and I could spend some more on it for the following season so it doesn't all have to be done at once.

Thanks

Chassis 33

6,194 posts

283 months

Wednesday 12th November 2008
quotequote all
I've never driven an MR2 so cant comment on the them, however I'm an avid e30 fan and from experience there's nothing much to go wrong with them, plenty of access to most things for when you do need to get the spanners out, however they do have an achilles heel that I've found on trackdays. Unless you mess about with fuel pickups or run more than 2/3rd full all the time you'll get surge on right handers.

Regards
Iain

RobM77

35,349 posts

235 months

Wednesday 12th November 2008
quotequote all
The earlier (pre '97?) MR2s suffered from a handling problem. I think it was roll oversteer caused by the engine being a bit too high, not unlike the Testarossa. This may not affect a modified track car, but it would be as well to check. This issue was fixed afterwards. Not sure what the multiplier for a turbo is in your capacity based classes, but the Turbo MR2s (2000cc turbo) can be jolly quick, and even as standard they're way faster than a standard 325i.

Oh, and to get the engine out of an MR2 (Mk1 anyway) you need to drop it out through the bottom. Make sure you can practically do that in your garage!

It's a tough call - the 325i is going to have far more tuning parts readily available for it, but the MR2 will be lighter, smaller and nimble.

Both cars have racing championships dedicated to them (Kumho Tyres series for the BMWs, if it's still called that; and the 750MC MR2 Challenge for the MR2s. If you can find a pre-prepared car then I'd go for an ex race car from one of those series.

Edited by RobM77 on Wednesday 12th November 08:06

RogueMotorsport

246 posts

189 months

Wednesday 12th November 2008
quotequote all
I'm massively biased towards the MR2 and don't have any BMW experience to speak of. The MR2 Championship cars are very capable but the regulations restrict the modifications so there's plenty of scope to improve both power and handling. The Toyota sprint series is very popular at the moment (http://www.toyota-sprint-series.com/) and MR2s are punching well above their weight in terms of bang for buck. Here's some in car footage from my (road legal) mk2 MR2 Championship car:

http://uk.youtube.com/watch?v=sN54Q3eWjPw

The last run is the smoothest and begins at 5:40 through the video. It was enough to place me 7th out of 52 with many of the cars finishing behind me being turbocharged, supercharged, four wheel drive or combinations thereof. I'm normally towards the front of the field in the MR2 Championship races, but by no means a stand-out driver.

There are a great deal of chassis and engine tuning options available - more for the mk2 and mk3 than the mk1. It may also be worth considering that the mk3 MR2 is ~1000kgs from the factory and the 190bhp engine from the Celica / Elise / Exige is a straight swap...

I'll be at the London Motorsport Show on the 22nd and 23rd of November at Brands Hatch and am happy to show you around an MR2 Championship car. If you hold a national race license you'll be able to hire for a session or failing that we can strap you into the passenger seat!

Best regards,

Patrick Mortell
Rogue Motorsport Ltd
01676 530222

jellison

12,803 posts

278 months

Wednesday 12th November 2008
quotequote all
I yused to think the same way on the FWD / RWD thing, till I had a Real Mini Cooper and then a Puma. Both Wicked - generally no fan of FWD though it has to be a Really good fwd chasis for me to like it.

Pum'a are awesome bits of kit - can you stretch to a Racing one?

Out of the other 2 close one, the front engine Beemer will be easier to control at the limit (but it is a Beemer!). No idea what shape the e30 is.

RobM77

35,349 posts

235 months

Wednesday 12th November 2008
quotequote all
jellison said:
No idea what shape the e30 is.
The E30 is the last model made with seperate headlight units - the shape that spawned the iconic first M3.

ICSD

Original Poster:

638 posts

235 months

Wednesday 12th November 2008
quotequote all
RogueMotorsport said:
I'll be at the London Motorsport Show on the 22nd and 23rd of November at Brands Hatch and am happy to show you around an MR2 Championship car. If you hold a national race license you'll be able to hire for a session or failing that we can strap you into the passenger seat!
I am going on 22nd so I will pop along thanks.

It's the SW20 that I'm interested and I've been looking at the 190BHP import version (G) which seems quite affordable - is a '93 or '94 OK? What needs doing to it?

RogueMotorsport

246 posts

189 months

Wednesday 12th November 2008
quotequote all
jellison said:
Out of the other 2 close one, the front engine Beemer will be easier to control at the limit (but it is a Beemer!).
MR cars are harder to control at their limits than FR cars, but's that's because their limits normally are somewhat higher. smile

jellison said:
No idea what shape the e30 is.

jellison

12,803 posts

278 months

Wednesday 12th November 2008
quotequote all
RobM77 said:
jellison said:
No idea what shape the e30 is.
The E30 is the last model made with seperate headlight units - the shape that spawned the iconic first M3.
Aha - see alot on council estates now!

I love the ORIGINAL 4 pot M3 though.

RogueMotorsport

246 posts

189 months

Wednesday 12th November 2008
quotequote all
ICSD said:
It's the SW20 that I'm interested and I've been looking at the 190BHP import version (G) which seems quite affordable - is a '93 or '94 OK? What needs doing to it?
Here's a quick guide I wrote on selecting an SW20 for use in the MR2 Championship, it should help with some of the basics. Don't be led by people who will tell you that Japanese versions are more powerful than UK versions - the Japanese models were rated in PS rather than BHP hence the slightly higher number!

Rogue said:
The mk2 MR2 had a ten year production run spanning from 1989 to 1999. During this time, Toyota revised the car five times - roughly every two years. The revision dates are as follows:

Revision 1: December '89 - August '91
Revision 2: August '91 - November '93
Revision 3: November '93 - June '96
Revision 4: June '96 - December '97
Revision 5: December '97 - May '99

Chassis
There were four different version of the MR2 chassis, designated SW20, SW21, SW22 and SW23. The SW21 and SW22 chassis' were designed for the left hand drive American market and were fitted with the 2.2l 5SFE and 2.0l turbocharged 3SGTE engine respectively. Neither are currently legal for the MR2 Championship. The SW23 chassis was available in the UK only and was outfitted with the lower powered 3SFE engine. The SW20 chassis is by far the most common and was available with the 3SGE engine in the UK and the 3SGE and 3SGTE engine in Japan. For the purposes of this article the SW20 and SW23 can be considered identical and are both suitable for use in the MR2 Challenge series. I will refer only to SW20 from this point.

The SW20 chassis was available in three forms, depending on whether it was purchased in the UK or Japan. Both regions received the T-bar model which has two removable glass panels in the roof. The UK had the alternative option of a "Moon Roof" which was a single large glass panel in the centre of the roof which could also be removed and stowed under the bonnet, while the Japanese market had the option of a "Tin Top" fixed roof. Tin Tops were not available in the UK and Moon Roofs were not available in Japan.

The T-bar version of the SW20 chassis is generally accepted to be heavier than the Tin Top or Moon Roof versions due to the extra strengthening in the roof area to combat scuttle. Other than that, weight differences between different versions of the mk2 MR2 are explained by variations in engine package, trim levels and options.

The only known change to the SW20 chassis was the introduction of two "dimples" in the rear panel at revision 3. This was to allow space for the reverse lights to be installed in the centre panel.

Since MSA regulations forbid glass positioned above the driver, the most suitable chassis would be the Japanese market Tin top SW20. The UK Moon Roof model would be a reasonable second choice, with the T-bar model coming in last.

Engine and Gearbox
The mk2 MR2 was available with a choice of four engines:

3SFE: UK Only - 118BHP - Not currently allowed
3SGE: UK, Japan - 158-200BHP - Championship legal (except BEAMS VVTi)
3SGTE: Japan, USA - 200-241BHP - Not currently Allowed
5SFE: USA Only - 135BHP - Not currently Allowed

The lower powered 3SFE engine was only available in revision 1 and some very early revision 2 cars in the UK. It was also the only model that could be equipped with an automatic gearbox. Although low-down torque is said to be very good on these engines, it is unlikely that anyone would want to consider them for race use.

Revision 1 and 2 3SGE engines are essentially the same 158BHP output, regardless of whether they are Japanese or UK market cars. The 3SGE engine in the corresponding Toyota Celica of the same year is also (as far as is required) identical to it's MR2 twin and can be interchanged. All Japanese versions of the 3SGE engines are available with an automatic gearbox.

Toyota improved the 3SGE at revision 3, increasing power to 172BHP, although there are many conflicting reports of this figure rangine from 172 - 176BHP. Other changes such as oil squirters below the pistons (as found on turbo models) help to cool the engine and increase it's longevity. Again, UK and Japanese models are the same and can be interchanged with the same engine from the Toyota Celica.

At revision 4, Toyota made some significant changes to the UK iteration of the 3SGE, while the Japanese version remained unchanged. UK cars were fitted with a system of exhaust gas recirculation in an attempt to bring down emissions. This in turn brought overall engine power down to 168BHP. The EGR system can be removed (or blanked off) under MR2 Championship regulations to bring power back up in line with the earlier model. UK cars were also equipped with transponder immobiliser systems making it very difficult to transplant the engine into another car (There are ways around this).

Revision 5 engines remain unchanged from the previous revision in the UK market, but changed radically in Japan. There, Toyota introduced a variable valve timing head, distributorless ignition and increased the compression amongst other tweaks, bringing power up to 200BHP and achieving the magical 100bhp/litre. Since only a limited number of these BEAMS VVTi engines were produced (rumored to be 1,000 installed in MR2s) and they change hands for in excess of £2,000 they are currently banned from the MR2 Championship.

Also of note, some late revision 5 cars were fitted with a limited slip differential which are not permitted.

The weapon of choice would therefore appear to be the higher powered revision 3+ engines, but real world experience would suggest that all versions of the 3SGE are very closely matched.

Suspension, Brakes, Wheels, Steering
All mk2 MR2s were equipped with power steering with the exception of revision 1 UK models which were not. Selection here is a matter of personal choice, although the non-power steering version is lighter.

Revision 1 MR2s have smaller brake calipers, disks and front pads than revision 2 onwards cars. Revisions 2 to 5 remain unchanged.

Revision 1 MR2s were fitted with 14" wheels as standard, and with slightly narrower tyres than later models. Due to the increase in disk and caliper size at revision 2, all later models were fitted with 15" wheels and wider tyres. While 15" wheels and tyres can be retrofitted to revision 1 cars, 14" wheels cannot be installed on revision 2+ cars. 14" wheels are not permitted in the MR2 Chapionship - this is to ease tyre supply rather than for any technical issues.

Standard shock absorbers and springs remain unchanged throughout the lifespan of the normally aspirated mk2 MR2. Japanese turbo models were equipped with uprated Bilstein shock absorbers (made by Toyota under license) from revision 2 and these make a good upgrade for n/a cars. A limited run of 500 normally aspirated "Anniversary Edition" cars split between UK and Japanese markets were fitted with Bilstein suspension as standard.

Revision 2 also saw some suspension geometry changes over revision 1, including a completely different rear subframe. Apparently this was in response to early criticism that the MR2 was tail-happy, although many consider that this was because people were unfamiliar with the mid-engine, rear wheel drive layout. Later cars are understood to be more predictable, though some claim that they've been "dumbed down" for the masses.

Anti-lock brakes were optional on all revisons of mk2 MR2. The system installed in Revision 1 -3 cars was fairly basic and (in my opinion) not well suited to racing - I would recommend disabling this system. Revision 4 and 5 cars benefitted from a more sophisticated setup with seperate channels to each corner (rather than one to each wheel at the front and a single line feeding both rear wheels), a deccelerometer and more sophisticated software. This system would be more suited to racing but I suspect that most race cars will be earlier models.

Other Considerations
All Japanese model cars came with climate control as standard. This is not a problem, but it will give you more components to remove when preparing the car. By law, aircon gas must be vented and disposed of professionally.

All Japanese vehicles are limited by law to 180kmh (~112.5mph). This can be disabled by either converting the speedo signal to read in MPH (essentially moving the speed limit to 180mph) or by simply cutting the speed input signal to the ECU (though this will illuminate the engine management light).

Revision 3+ MR2s command a significantly higher price than previous revisions, due to improved styling and power. T-Bar models are more sought after and typically fetch up to £500 more than other types.

Japanese normally aspirated models are known as "G" or "G-Limited". UK models are known as "GTi-16" for 3SGE engined cars or "Coupe" (no badge on the rear) for the 3SFE engined version. Turbo models are "GT" or "GT-S".

All versions of the MR2 were supplied with a rear spoiler with the exception of the 3SFE Coupe model. Revision 1 and 2 cars had a three piece spoiler that extends along the rear wings. Revision 3 and 4 cars had a single piece spoiler of a similar design but without the wing extensions. Revision 5 cars were fitted with what is affectionately known as the "Comabt" spoiler, consisting of two side supports and a central adjustable "blade". This can be positioned to (allegedly) affect downforce.

Exhaust systems vary between engine versions as well. Revision 1 and 2 engines have the same manifolds, while the revision 3 is different but shares the 4-2-1 layout. revision 4 and 5 cars have a 4-1 exhaust manifold design. All japanese model cars have a catalytic converter, as have revision 2+ UK cars. De-cat pipes are available to remove them.

Revision 3+ cars are fitted with a different design of rear light - they are more rounded and have the reverse lights in a colour coded centre panel.

Revision 1 "G" grade Japanese model MR2s were available with manual wind-up windows.

Internal side impact door bars were installed in all models from Revision 2.
Cheers,

Patrick

Edited by RogueMotorsport on Wednesday 12th November 14:20

ICSD

Original Poster:

638 posts

235 months

Wednesday 12th November 2008
quotequote all
That's great thanks - I'll definitely come and see you and maybe get a ride.

A couple more queries, do you think that the MR2 is do-able for £2k and also, can you explain the handling issues and the right way to correct them?

I have to say that the E30 can be snappy as well (I have already had one on the track) so I'm not that worried about the MR2.

RogueMotorsport

246 posts

189 months

Thursday 13th November 2008
quotequote all
ICSD said:
A couple more queries, do you think that the MR2 is do-able for £2k and also, can you explain the handling issues and the right way to correct them?
£2k is what I would spend on the base car - for that you'll be looking at a '94+ car in good condition. You can find cheaper if you look hard (especially at the moment) but normally cash saved on the initial purchase will end becoming cash spent on rectifying problems later. Your biggest initial gains will be from weight saving which cost nothing but time.

In my opinion, there are no issues with the handling - it's simply a case of becoming comfortable with the way the car feels. Revision 1 cars are more prone to snap oversteer, but you'd want to be looking at revision 2+ anyway for the bigger brakes. Changing the fourteen year old rubber bushes for some polyurethane items will help the chassis communicate what is happening to you better and made a considerable difference to my racing.

Patrick

mat205125

17,790 posts

214 months

Thursday 13th November 2008
quotequote all
A cheap E30 325 is likely to be quite tired and worn

rallycross

12,807 posts

238 months

Thursday 13th November 2008
quotequote all
From my experience in road cars (have owned both the above) I would have said the BMW.

But then after having been out on track in one of the 750mc MR2 challenge cars, I was amazed at how well they handle, after just a few basic mods they are great fun.

If you are thinking along these lines go and talk to Rogue at the motorsport show, I think they may be doing some demo laps, so you will get an idea of what I mean.

I was so impressed by the MR2 I bought one and I am now racing one in the 750 mc MR2 challenge, its still road legal so you can use it in a number of series eg sprints, BARC tintops, SEMSEC, trackdays, I even did an autocross in mine it was great fun.

And you can buy a decent base car from £1k upwards if you want to build it yourself.

Edited by rallycross on Thursday 13th November 16:18

ICSD

Original Poster:

638 posts

235 months

Friday 14th November 2008
quotequote all
I'm starting to think that what I'll do is go for the MR2 but develop it slowly so it's fairly inexpensive to start with.

Probably just fit a couple of seats with 4-point harnesses and get some track wheels and tyres and that'll do for now.

Looking forward to seeing Patrick at Brands.

Thanks everyone