Converting SII V8 back to 2.25

Evening, I'm looking at converting a SII V8, which is missing the V8 engine, back to a standard 2.25 petrol. I understand that the bulkhead has been adapted for a V8, the gearbox has been fitted with a V8 conversion plate and the electrics modified. I'm not too concerned with changing out the gearbox and electric mods, but I'm not sure about the bulkhead. Can anyone tell me what work is probably needed to the V8 bulkhead to make it ready for a 2.25 petrol, whether it involves removing the bulkhead and whether there is anything else to watch out for? Cheers, Richard.

not usually altered much at all, probably find there is a chunk out of the p/s footwell to allow access to the rear plug, also worth checking the engine mounts, most v8's use adapted mounts on the engine and keep original chassis mounts in the correct position but not always the case

cheers steve

You do know the V8 is more economical than the 2.25 don't you ?

Dr_evil said:

You do know the V8 is more economical than the 2.25 don't you ?

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And better

Dr_evil said:

You do know the V8 is more economical than the 2.25 don't you ?

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Wait.... WHAT!?

How is it more economical? I want a V8, but always thought the 2.25 was better!

Put an old 3.5 in rather than the 2.25, gotta be better option. My 2.25 is thirsty as, a v8 couldnt be much worse plus you can put rangie diffs in and get more mpg again.

tomtomtom said:

Wait.... WHAT!?

How is it more economical? I want a V8, but always thought the 2.25 was better!

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which fcukwit told you that


V8 has more power, a great noise and in a series is far more economical than the 2.25

You do need better cooling and some small mods to fit though

Dr_evil said:

which fcukwit told you that


V8 has more power, a great noise and in a series is far more economical than the 2.25

You do need better cooling and some small mods to fit though

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But not if it has been moded already like his

bencorkill said:

But not if it has been moded already like his

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but he wasn't the one who asked

I was thinking of keeping the SII as original as possible and with the V8 still to be fitted, I'm also a little leery of someone else's modifications. But I didn't know that a V8 would be more economical than a 2.25 ltr. That may make me change my mind....

its better in every way as long as you don't floor it too harshly, if the conversions been done right (unlike mine was)

Should be a chunk out of the passenger footwell, modded engine mounts to raise it up slightly, spigot adaptor if not you need to make a custom bush up like I did………then I gave up and decided I wanted a 5 speed box so fitted an R380

If you were really worried about wrecking your Series box you could find a low compression v8 possibly (military) or just a carbed 3.5 in mild tune. Would be easier on the drivetrain than something pushing out 150hp plus (or double a 2.25) like a 3.9 etc. It would be the torque that would snap stuff though and I don't think an old 3.5 would have a massive amount more than a 2.25 in good tune? But someone else on here would know better than me.

Do it, if not purely for the noise. Doesn't matter how fast you are going in a series, 30mph feels like 70mph in my Mondeo!

3.5 would have 130 stock on carbs iirc, think I've even read the stage ones sometimes had 90bhp but that was due to carb restrictors in the inlet or something like that, so you just remove them

Just don't floor it off the mark and you should be fine

Correct info re MPG and V8 Smooth or what

I've had a few v8 series vehicles and yes I have broke stuff, mostly half shafts and nearly every time was snatching second and giving it some lacehole.
Normal driving even towing 2 ton no problem or perhaps I should say no worse than a 2 1/4.
As for economy, a 9.35 compression 3.5 v8 on HIF SU's in an 86" RR diffs, overdrive and radials + long run to Wales 30 mpg

I've also thought about building a V8 just for gas only. ie very high compression, injection manifold with gas injectors where the petrol injectors should be and edis 8 ignition.
I even spoke to the engine builder at RPI who said it would work great

oooooh 30mpg sounds nice I only get 25 in the disco so if its that in the 88 I'll be happy

Ceramic coatings will be grand Bro will be experimenting with ceramoc coatings for a dare I say it economical more powerful 3.5.

P.S Dr's engine is VERY economical. It does 0.0 MPG as its never run!!! Teehee!!!