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Carb engines and IVA
frozennorth - 27/4/20 at 08:44 PM

I've heard that it can be pretty difficult to get post - 1995 carb. engines to pass the current emissions standards required for the IVA; which is a bit of a nuisance, as I intend to use a 1999 Fireblade engine in my newbuild. Does anyone have any experience of this? I don't mind fitting a cat if necessary, or maybe some other mods..

SJ - 28/4/20 at 06:58 AM

My understanding is that it is hard but can be done, but using tricks like air bleed valves to get the emissions low enough.

flak monkey - 28/4/20 at 11:03 AM

It's made harder with bike engines as they were never designed to meet car emissions standards. Bikes always have had a higher limit than cars, and even now its still 4.5%CO and visual only. No HC test.

For post Aug '95 cars (until 2002) it is 0.5% CO at idle or 0.3% CO and 200ppm HC at 2500-3000rpm.

Basically it means a CAT will be required. But you are ultimately trying to get an engine to pass a test it wasn't designed to - the cam profiles in bike engines don't help either.

That said, it's not impossible, it's just not simple.

russbost - 28/4/20 at 02:02 PM

If it's a new build why use an engine which is less than ideal in a kitcar anyway in a situation that has the potential to cause a ton of grief? If it's just because you already have the engine, then I would suggest flog it & buy something more suitable like the 89/90 ZX10 or slightly later ZZR1100 engine, far better in a car than the blade & won't need to pass CAT emissions.

Alternatively put the money towards a later injected bike engine which can be relatively easily thro' the test with a power commander & a CAT

frozennorth - 28/4/20 at 08:25 PM

Thanks for the feedback gentlemen, I don't think I will continue with the Fireblade engine: it's a pity. I last used it in one of my hillclimb cars and it's a cracker: probably best used again in another hillclimber. Anyway, I'm going to switch to a Hayabusa as I have one to hand and I'm familiar with them, having used one in the past with good results. Should be good in a road car...

russbost - 29/4/20 at 07:08 AM

Is this going into a 7 style vehicle, ie engine longitudinal? If so from what I've heard the 'Busa needs an accusump even for road use & for serious track use you'd need to dry sump, there are also various baffled or swinging pickup sumps available

frozennorth - 29/4/20 at 08:37 AM

It's going into a Tiger Avon; I fitted one in a Stuart Taylor Phoenix hill climber / sprinter before, and made my own sump and swinging pickup; combined with a bit of baffling and an accusump it worked fine, and I will do the same again with this one. Cheers, John