[Mk2] [Turbo] Rev1 to Rev2 to Rev3 conversion!

[fishface]

Hi all. Sorry i know youve probably seen this question a hundred times before but i have spent half the day trawling the forums and am still confused so wondered if somebody could answer a few questions please? We have a Rev1 turbo which was running with a CT20B, Cometic head gasket, decat, induction and EBC. It ran really well but something in the bottom end gave up the ghost at Donington in November! We now have a Rev2 bottom end which i am in the process of fitting forged rods and pistons to along with all new bearings and new oil and water pump. We also want to fit the full Rev3 top end conversion with the head, cams, manifolds, throttle body, fuelling system and ECU. Right the questions are............

1) Which cambelt do i need? Are they the same? Are the Rev3 cam pulleys adjustable like the Rev1 ones?
2) Can i use the Rev1 engine loom with repinning at the ECU and if so do i need to add wiring to it for some of the sensors? Would it be much easier just to use a Rev3 engine loom?
3) Will i need to change anything in the other parts of the Rev1 loom?
4) Will it work ok with the Rev1 mechanical speedo?
5) Will my Rev1 throttle cable work?
6) Do i need to change the downpipe for a Rev3 one?

If anyone has any other help or advice they could give that would be great! Thanks Andy.

Apologies in advance as im sure i will have a million more questions in the next few weeks!

[Shmed]

Hello mate,

I have a rev 2 block and rev 3 head, so can answer most your questions:

1) Which cambelt do i need? Are they the same? Are the Rev3 cam pulleys adjustable like the Rev1 ones? Rev 2 Cambelt, I don't think rev 1 or rev 3 are adjustable as standard. Buy some off Flea Bay for about £80 a pair.
2) Can i use the Rev1 engine loom with repinning at the ECU and if so do i need to add wiring to it for some of the sensors? Would it be much easier just to use a Rev3 engine loom? You could repin it. You will likely use the existing alternator so oval/round plug not an issue. Rev 1/2 lambda is only 1 wire, rev 3 is 4, so might need some extras there. 2Bar Tuning has a pinout diagram.
3) Will i need to change anything in the other parts of the Rev1 loom? AFM is removed so wires could be used to wire IAT sensor. There might be others, but can't remember
4) Will it work ok with the Rev1 mechanical speedo? If the sender in the gearbox is mechanical (i.e. rev 1), and the speedo is from a rev 1, then yes. Otherwise, no.
5) Will my Rev1 throttle cable work? No. They are slightly shorter than the rev 3 ones
6) Do i need to change the downpipe for a Rev3 one?Not necessarily. The manifold needs to change, but downpipes can be interchangable between revs (I think...)

[Shmed]

Just spotted that you were going to add Rev3 ECU. You should also add rev 3 injectors and rail (rev 2 wont fit the head - easily anyway). Also you should consider swapping the coil to a rev 3 one too.

[gazrev1tubby]

It's much easier to get a rev3 engine loom, all you'll need to do, is repin a few connections to the chassis loom in the boot, and a couple at the engine bay fuse box.

The rev1 throttle cable can be used

Pretty sure it's a rev3 cambelt you need, as i'm sure the head denotes the correct belt

The cams are adjustable like the rev1 ones, in the sense that the dowel pins can be moved for adv/ret

You will also require the correct rev3 sensors for the swap, namely:

fuel pump resistor pack
coil/ignitor
map sensor
mat sensor
ait sensor
rev3 leads and dizzy cap
injector resistor pack
4 wire lambda sensor
rev3 ecu - obviously

The speedo drive in the gearbox controls the speedo, so you just continue using the mechanical drive and rev1 clocks

The downpipe will bolt up fine, it fits to the turbo - so the manifold makes no difference

You'll also want a rev3 manifold heatshield

[fishface]

Ok thats confused me lol! Thanks for the replies though! The gearbox is staying but i wondered if the Rev3 picked up any signals from the speedo cluster that wouldnt be there with the mechanical speedo? We will be fitting the full rev3 top end including the fuel rail and injectors so no problems there! I think it also includes the MAT, IAT and lambda sensors! We already have the Magnecor 8.5 mm HT leads so will these be ok? I think all i will end up short of are the MAP sensor and the coil/ignitor if anyone has any they want to sell? With the downpipe i thought i had read that the turbo sits slightly lower on the Rev3 manifold but if i dont need to change it all the better! Will probably heatwrap the manifold and downpipe and fit a turbo cosy as we never had a turbo heatshield anyway lol!

[Shmed]

From experience, it's a rev 2 belt you need. I have pics of the rev 3 belt not fitting. Cams on rev 2 and 3 have the same number of teeth, the difference is on the water pump where the rev 2 has one more tooth. That makes the rev 3 belt one tooth too short.

[Shmed]

Oh, and I also 100% had to swap my rev 2 cable for a rev 3 cable. The rev 2 one held the throttle ever so slightly open. I guess you could get round it by modifying the bracket that secures the cable tithe throttle body.

[fishface]

From experience, it's a rev 2 belt you need. I have pics of the rev 3 belt not fitting. Cams on rev 2 and 3 have the same number of teeth, the difference is on the water pump where the rev 2 has one more tooth. That makes the rev 3 belt one tooth too short.

Thats good info! Not heard that before! Does a Rev3 pump not fit the Rev2 block then?

[Shmed]

I don't think that a rev 3 pump fits a rev 2 block. There probably isn't much point in making one fit either. The bottom end determines the belt you need. I fell foul of forum speak and bought a rev 3 belt, lost some cash on that

Also, idler pulleys and tensioner bolt need to be from a rev 2 assuming you will be changing them.

Engine hangers are different, some of the rev 3 head pipework is different to the rev 2, inlet manifold.

Have you got a rev3 donor, or just buying the head?

[fishface]

I don't think that a rev 3 pump fits a rev 2 block. There probably isn't much point in making one fit either. The bottom end determines the belt you need. I fell foul of forum speak and bought a rev 3 belt, lost some cash on that

Also, idler pulleys and tensioner bolt need to be from a rev 2 assuming you will be changing them.

Engine hangers are different, some of the rev 3 head pipework is different to the rev 2, inlet manifold.

Have you got a rev3 donor, or just buying the head?

Ive got the Rev2 belt so will be easy enough to test fit that before i buy a new one anyway! The head comes with the water pipes but im not sure about the hangers? Does the drivers side engine mount all fit together onto the Rev3 heador will i need to change any of that? We are buying the head with the manifolds, injectors, fuel rail, pipework, cams etc!

[Peter Gidden]

O/S engine mount is same for all SW20 MR2s.

[Shmed]

Yep, engine mounts all the same as Peter says. Little things are different, like Cam belt covers.

[fishface]

Cheers guys! Any more tips?

[Shmed]

The hard pipes that go under the dizzy are different on rev 3, I think it's part of the oil catch can bracket. Standard oil to turbo pipes are different, the banjo is bigger? on rev 2, but that might not be a problem if you already have at ct20b fitted. Can't remember the other problems i had.....

[Shmed]

Here's my build site, Specifically the bit with cambelts, though I stopped updating it after a while.
.

http://shmedz.com/Build/EngineBuild_03.htm

[bobhatton]

I don't think that a rev 3 pump fits a rev 2 block. There probably isn't much point in making one fit either. The bottom end determines the belt you need. I fell foul of forum speak and bought a rev 3 belt, lost some cash on that

Also, idler pulleys and tensioner bolt need to be from a rev 2 assuming you will be changing them.

Engine hangers are different, some of the rev 3 head pipework is different to the rev 2, inlet manifold.

Have you got a rev3 donor, or just buying the head?

All blocks are the same, Rev 1, 2, 3 and on. Oil and water pumps fit all blocks.

On Rev 3 the oil pump pulley is bigger so you would then need the Rev 3 cam belt. If you have a Rev 1 & 2 oil pump pulley use the Rev 2 cam belt

[fishface]

Cheers again for the replies! Is the Rev3 oil pump better or worse in your opinions? I was planning on changing both oil and water pumps anyway!

[bobhatton]

Cheers again for the replies! Is the Rev3 oil pump better or worse in your opinions? I was planning on changing both oil and water pumps anyway!

I think the much later 1998 on 5SFE and3S pumps are wider so pump more oil.

[Peter Gidden]

Rev1/2 oil pump will only fit Rev1/2 sump.

5S oil pump will only fit Rev1/2 sump.

[fishface]

So which pump would you advise to use? I picked up the top end today so ive got the head and cams with pulleys, cam cover, inlet manifold and throttle body, hardpipes, water pump and thermostat housing, water pipes, water outlet tree, cam belt covers, injectors and fuel rail, fuel pump resistor pack and a 4 wire lambda sensor! So i think i now need ECU, MAP sensor, AIT sensor, coil/ignitor, injector resistor pack, engine loom? Do i use the Rev2 cambelt tensioner? Thanks again for all your help and sorry about all the questions!