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Hi guys,

I recently installed a single stage boost controller to give my car a little bit more power after nearly, and I do say nearly coming second in a drag with an XR6 Turbo.

Anyway stock boost was set at about 6-7 pound so I added an extra couple of pound and the car now boost to about 9-10 pound.

This extra boost has created some sort of problem with the acceleration which becomes jerky when taking off on the new boost level (fast launches)

Does anyone know a)why this is happening

b)How to fix it. I have tried reseting my EM with no avail.

Maybe I need a fuel cut defender??

Cheers

Jevan

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Guest RedLineGTR

It would be your spark plugs if they at a stock gap..when i added some extra boost i needed to gap them down to 0.8 which most people use. But it also depends what u mean by jerky since i only got it when i was in the 4500rpm range or something abit futher down. Might be something else but yah..

I have just boosted my car up a little and noticed now when i go upwards of 4500rpm it starts to make lots of small back fires, my thoughts was the plug gap but not sure yet, is that what you meant RedLineGTR?

QuickR33Melb mine is not jerky on take off but i just had a prob with my bov leaking and it made the car shudder and go nowere when it came on boost, maybe your new boost controller is leeking

RE: the drag with the XR6 Turbo - my brother's just bought an XR6 Turbo UTE and we measured 6.6 seconds 0-100 with an AP22 performance meter, with me in the passenger seat and a bit of other load as well. He revved it a bit with foot on brake, but it was rather gentle and no wheel spin at all. The best I've managed so far in my GTS25t is only 7.4 seconds on standard boost, but I don't launch *really* hard. (I certainly launch harder than he did, though). I reckon he's a lot faster than me, unfortunately. :D (I'm sure a skilled driver could do a lot better than me in my car - I accept that. Unless my car has a problem, but it's had a few dynos and the tuners reckon it's just fine)

Greg.

Thanks guys for the replies.

I took the car out near the Melbourne Airport last night, for those of you that live elsewhere it's a fantastic place to cut loose as there are long straight roads and NO cops! Just service roads for the airport. The problem is exactly how Gold Rays & Miss*33 described!

I wound the boost back a bit and the problem started at about 4500rpm. I'll look at re-gapping the plugs in the next 24 hours and let everybody know if this solved the problem.

As for the XR6 Turbo the one I mentioned was a sedan, most liekly an auto and had 3 people including the driver. I still have alot of respect for those cars. It's nice to see Ford creating a bit of a cult car and taking a leaf for Japanese success in automotive manufacturing.

I'll be interested to see 18-25 year olds driving them in ten years time when there cheap and fully modified!!!!

definitely spark plug gap.

If you do a search, this has come up countless times.

and 99% of the time, the spark plug gap is the issue.

if you haven't already changed them, get yourself a set of copper plugs ($4 each) gapp them to 0.8mm (if they are not already gapped to that) and your probs are solved.

Your a funny man Robo.

I dropped the car off this morning at Ultratune in Collingwood.

I'm good mates with the owner so I buy him Macca's for lunch and he does an hours work for free. I also told him to check the air fuel mix which may need adjusting

I will keep you all posted and let you know what the results are when I take the car out for some late night track work near the airport.

I got the car back and it is boosting without a problem!

Thanks to everybody for their advice it is greatly apprieciated!

My mechanic is at a loss to explain how that slight adjustment can stop the jerky engine but it works so I'm happy.

Thanks again guys I'll buy you all a drink one day.

PS- Have a look on ebay for some good skyline parts

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