Thread: Unichipping a 4lt V8

Why not call Graeme Cooper who are Unichip agents in Sydney.
He told me that the gains on a GEMS engine are not great as the timing is already mapped and has knock sensors. If I recall he said gains were maybe 5-8%.
On a 14CUX 3.9 , you pick up a LOT from timing map changes with an average of 15% increase in power. I get slightly better economy in town but little on the highway.
You will never recover the cost in fuel economy gains.
Regards Philip A

Thanks Philip, that was what I was after, cost v's benefit etc.

Yeah, if you're talking 4.0 w/ GEMS or Bosch, the improvement is marginal but an improvement all the same.
Here is my dyno chart - this chart shows results with std exhaust, std diffs and 245/75x16 tyres....


I've since changed the exhaust, changed the diffs and changed the tyres - she still drinks petrol like a true V8 Rover but will get up 'n' boogie when required.
I'm going start playing with ROVACOM, I'll have my UNICHIP for sale if interested....

Hardy

Oh BTW - I think it was about $1100 or $1300 all up incl the dyno tune.
$5000 towards a supercharger would be money well spent.

Or $300 towards a lovingly cared for 2nd hand UNICHIP - would suit any EFI V8....

Its a pity that they did not do a dyno run in third from 1000 or 1500RPM. The area you use most in an auto is 1000-3000 RPM. It looks like the graphs are moving further apart down low and if so this is a good thing. As it is the graph is pretty meaningless as you only go over 3000RPM for a small time in an auto anyway.
My 3.9 has almost 60% more power at 1500-2500RPM with unichip,heads and Thor manifold. You can juuust feel the difference LOL.
Its funny that the 4.0 graph looks a lot like the 3.9. The stock engine is well tuned in the mid range but you pick up lots at both ends.
Did they REALLY take the engine to 6200RPM?????
Who was it Graeme Cooper?
Regards Philip A

Originally Posted by Hardy

I'm going start playing with ROVACOM, I'll have my UNICHIP for sale if interested....

Hardy, I'm definitely interested in the UniChip for my P38A. I'd like it so I can get the dual mapping - one for petrol, the other for LPG.

Ron

Phillip, you're dead right right on all counts.

6200 rpm - Yeah, I cringed when I first saw it.
I don't know why the dyno didn't show the lower rpm.
I can't remember when I last hit 3500rpm - in the bush that is.

T'was CNJ at Slacks Creek, Brisbane - Kelvin was the chaps name, very knowledgable in his field. He had a lot 'young fellows of oriental descent' hanging around, taking phonepics of their Honda SuX2000's and ****box 1 Millions etc. Not an expert on Rover V8's but I'd still use him again if ever the need arose.

I want a supercharger. Or a new TDV8, when they come out....