Come on you Lot - I need to pick Your Brains !!


I have been looking for and have found a Rally 2/4 Engine for the Sirion (In fact Iv'e found 2)
I am still doing some checking to make sure they are the correct one's.(107bhp version)
So how hard would it be to remove my Sirion 4 Track Engine and replace with the Rally 2/4.?
Do I need any special Electronics from the Rally 2/4 - I know I need the ECU - Do I need anything else?
I think the electronics will be the problem rather than mechanics.:)

Give me some good idea what I need please.;)

Cheers, Bob F.

Hi Bob, Not sure, about this

Hi Bob,

Not sure, about this but maybe worth considering the following:

- The rally 2 & 4 uses a Quick syncro gearbox, wil yours be okay?
- Is the clutch in your car rated for the more HP you are putting in?
- Will the drive shaft be okay? I'm guessing yes.
- Will the radiator be okay for this engine?

Hopefully everything else should marry as I believe the engine itself should the same as the one you are taking out except tweaked.

Shame you couldn't find someone to remap the one you have now? I know of one tuner for the YRV based in Surrey called Bigperformance who claims to map the normal car from standard to 100BHP.

'53' Plate Yellow YRV Turbo/ '53' Plate Black Subaru Impreza WRX STi PPP

'12' Plate Mazda MX-5 2.0 litre NC 3.5 Venture Roadster 160BHP
'15' Plate SEAT LEON 184 FR TDI. 240BHP/500nm Torque.
Past: '53' Plate Yellow YRV Turbo Approx. 150BHP

Rally 2/4 cars were altered

Rally 2/4 cars were altered as follows. Modified exhaust cams, ECU and Free flow Air filter. The bushes in the gearbox were changed to give a 'short throw' gear change. The suspension was lowered by 20mm with stiffer, uprated springs, and the brake pads were uprated. I don't know of any other mods so suspect the clutch, radiater etc will be standard. I would certainly double check the engines Bob as there were so few Rally's actually made, there can't be many about.

I suspect if you have found the correct engine it would not be too difficult to swap but getting the right ECU would be essential. Then there's the unknown 'how would it drive without the suspension/gearchange mods'?? I suspect you could just fit competition type pads to uprate the brakes.

All sounds a bit risky. May be best to sell yours and buy a Rally. I know where there's a cracking Rally 2 for sale!!!

Simplest route

Bob, I would have thought that Trevor Levy made the minimum changes necessary to the standard engine. Thus my advice would be to follow the same route and replace parts. From what he told me he would have given up on the ECU and concentrated on cams and free-flow air filter. You can always have a chat with Trevor to confirm this.

It may be less expensive than buying new cams, to buy a second-hand engine and pinch them off that. If you put your old standard cams into the second-hand engine you would have a saleable standard engine to defray your expenses.

Changing the engine sounds a horrendous and unnecessary option from which I would shy and in any case you can't guarantee the state of a second-hand engine although the cams are less likely to be worn than many other parts.

YRV Tony

YRV Tony

What power is the Sirion

What power is the Sirion Fourtrak? Is it 86 bhp or 101 bhp?

If it's the latter then a more fee flowing exhaust and better induction will give you a couple of extra bhp, otherwise Ian at Big Performance is your man for a remap. The website is a bit of a dogs dinner and doesn't mention Daihatsu, but he appears to be able to tune anything with an engine!

Replacing the lump might seem the best way forward, but I would suspect that you would need the ECU from a rally 4 rather than a Rally 2. The 4wd adds weight and the fuel and ignition mapping probably alters the power and torque curve to suit the extra weight.