difference between rev1 and rev 2 tubbies?

[darkz]

hey guys, just wondering if you knowledgable chaps could enlighten me on the differences between the rev 1 and rev 2 turbos, regarding engine differences/turbo? and body changes..
cheers. How can i tell which engine is which?

[TomThumb]

quore this has been done plenty. but as iv had a few beers i have the compelling urge to answer your noobish question! (via google)


* position and orientation of oil filter changed.
* different internal engine parts, e.g. pistons, con-rods etc.
* turbo charger changed from Toyota CT26 to CT20B (same intercooler though).
* boost pressure raised from about 10 to about 13 PSI.
* power output raised from 220 to 240 BHP.
* compression ratio slightly lowered.
* injector size increased from 430cc to 540cc.
* fuel cut threshold raised from about 12 PSI to about 18 PSI.
* head and inlet path completely redesigned. TVIS removed, 8 'independent long ports' reduced to 4.
* throttle body increased from 55mm to 60mm.
* inlet valve lift increased from 8.2 to 8.7.
* different, smarter engine ECU, more tolerant of poor fuel, different connector pin out.
* air flow meter removed.
* intake manifold inlet air temperature sensor added. i.e. after turbo and intercooler.
* ECU now modulates the turbo VSV to achieve variable control of boost pressure rather than either open/full or closed/reduced. Control of boost now quite subtle when ECU is unhappy because of temperatures, detonation, speed, etc.
* location of valve shims moved (someone said this was to stop problems with them falling out). If the manual is to be believed, this makes adjusting the valve clearances a much bigger job as on the revision 3 it involves removing the camshafts (might as well replace the timing belt whilst you're at it).
* exhaust valve clearance increased by 0.08 mm (probably. valve clearances is one question I'd like answered direct from Japan. They are probably the same as the UK GT4s, but it would be nice to be sure).
* oil pan changed from a one piece pressed steel part to a two piece affair, the upper half being aluminium, the lower half being pressed steel.
* No. 1 compression ring now described as 'stainless steel' in GT4 manual/supplement instead of just 'steel'. Oil ring is described as 'stainless steel' instead of 'a combination of steel and stainless steel'. No. 2 compression ring remains described as 'cast iron'.
* idle speed perhaps slightly reduced (need to check this out on a rev 1 or 2 car, my stickers say 750 rpm, I've a feeling rev 1 & 2 was 800 rpm).
* exhaust part numbers changed. Revision 2 part number for the front pipe is superceeded by the revision 3 front pipe part number. Back-box part numbers different. Unknown to me whether they are actually different.
* Coolant drain plug added on cylinder block (on older engines the manual says to disconnect a by-pass hose when changing coolant).

(Please note a lot of significant chassis improvements were already made for revision 2, although revision 3 ABS is probably much improved including the addition of an accelerometer.) Its rumoured that the USA never got the later improved engines, even though the american version of the MR2 turbo was sold there until 1996 (in very small numbers after 1994 though).


but you can get the rev 2's upto the power of rev 3's quite easley

[Peter Gidden]

Ummm, unless i've been awake far too long, these are differences Rev1/2 to Rev3...

The easy way to tell the difference Rev1 to Rev2 turbo engine is vacuum pipes coming off the vtop of the throttle body: 1 for Rev1 and 2 for Rev2.

[Goldy]

Ummm, unless i've been awake far too long, these are differences Rev1/2 to Rev3...
.

Think you might be right there.... someone might have had 1 too many beers

[TomThumb]

oops i thaught he said rev 12 - 3!

just rev 1-2 oops

the queen mother made me do it

[darkz]

lol yeh i knew the most of the diff between rev1/2 and 3 .. altho a few there i hadnt thought about. was just interested in changes frm rev 1 to 2 lol. think ur rite on the beer front . wat about on the outside? didthey change any of the external bits aprt from brakes alloys and suspension? didnt they make the front plastic lip into one piece instead of 2? trying to figure out what engine i have,as the car is plated as a 94, but is def a rev1/2 engine and chassis, just with rev 3 styling
cheers

[Quigonjay]

yeh just 1 or 2 minor differences on the outside - rev2 got deeper lip spoiler + change from matt black to gloss, side strips on rev 2 have a 'tint' of body colour where rev1's are black, rev 1 has yellow fogs, you know about the wheels, on the back panel between the lights rev 1 has 1 line across it (in the middle) rev 2 has 2. Thats about it i think

[Rory]

Rev 2 cars got bigger better brakes also and the suspensions was lowered and handeling improved. Rev 2 cars also got 15" wheels as std. (Rev 1 have 14") Steering wheel also changed to the later style...

Rory

[matt_mr2t]

Whats this about the pipe coming off the throttle body?
There's a clear difference between rev1/2 engines and thats the shape of the inlet. Rev1's are longer, rev2's are shorter and straiter.

I think the pipes refered too might actually be something to do with extra's. I saw a rev2 on the same year as mine with LSD and that had the twin pipe formation. That was the only difference between the cars.

[Peter Gidden]

Whats this about the pipe coming off the throttle body?

Small vacuum pipes on top of the throttle body.

All the Rev1s i have seen have one heading off towards the charcoal canister, and all the Rev2s have 2, both next to each other.

[matt_mr2t]

Well I have one that kinda goes in a loop if that makes sense.
Take a look.
http://img.photobucket.com/albums/v361/ ... Samcos.jpg

It's a Jan 1992 J reg so one of the very first rev2's

[JJ]

SO we've agreed on :

Rev 1 to Rev 2 Turbo :

Chassis & Interior :

Deeper front air dam
Honeycomb plastic between the rear lights changed its design slightly... more boardering.
15" Wheels
White fog lamps as standard
Bilsteins as standard with stiffer lowered springs
Longer track control arms to the rear
Bigger brakes all round
Different steering wheel ( less bulky 3 spoke )
Shortened gearknob
Tweeter covers are meshed
Larger door speakers used 6.1/2"
Alcantara seats tougher on the GTS models

Running gear

Dual / Triple syncro gearbox used as earlier ones were like chocolate.
5mm HT leads used, different coil pack
Throttle body adapter plate changed ( option of TRAC )
Throttle body changed - geared down - reduce snap open throttle on light throttle.
Cam cover partially different ( throttle section holding down points )
Charcoal canister different
Vac hoses to charcoal canister ( 2 on rev 2 ! )
Intake manifold support bar adopted
Head partially different - Exhaust manifold gone from 7 bolt to 9 bolt ( common problems of warping / cracking ! )
Stainless steel piping network around engine ( prone to corroding on rev 1s )
Block coolant take off nozzle increased diameter
Temp Gauge sensor connection different - gone from spade to connector
ECU is different
Engine harness is different


and thats all I can think of for the time being !

[JJ]

Well I have one that kinda goes in a loop if that makes sense.

Matt, yours has been modified... the chances are the charcoal canister doesn't exist any more ? or leftt o breath to atmosphere .. any petrol smells coming from the engine bay ?

[Ed]

SO we've agreed on :

Rev 1 to Rev 2 Turbo :

Chassis & Interior :

Deeper front air dam
Honeycomb plastic between the rear lights changed its design slightly... more boardering.
15" Wheels
White fog lamps as standard
Bilsteins as standard with stiffer lowered springs
Longer track control arms to the rear
Bigger brakes all round
Different steering wheel ( less bulky 3 spoke )
Shortened gearknob
Tweeter covers are meshed
Larger door speakers used 6.1/2"
Alcantara seats tougher on the GTS models

Running gear

Dual / Triple syncro gearbox used as earlier ones were like chocolate.
5mm HT leads used, different coil pack
Throttle body adapter plate changed ( option of TRAC )
Throttle body changed - geared down - reduce snap open throttle on light throttle.
Cam cover partially different ( throttle section holding down points )
Charcoal canister different
Vac hoses to charcoal canister ( 2 on rev 2 ! )
Intake manifold support bar adopted
Head partially different - Exhaust manifold gone from 7 bolt to 9 bolt ( common problems of warping / cracking ! )
Stainless steel piping network around engine ( prone to corroding on rev 1s )
Block coolant take off nozzle increased diameter
Temp Gauge sensor connection different - gone from spade to connector
ECU is different
Engine harness is different


and thats all I can think of for the time being !

Geek

[matt_mr2t]

I dont even know what the charcoal cannister is, it was like that when I bought it. At that stage it only ever had an exhaust and airfilter.
I can't see any reason why they would have done that?
It doesn't smell of fuel although it's crap on petrol lol.