Well I had my car setup today at TOTD, I wanted a road setup really but left it too late and I wanted it done before Central Day. Probably just as well I didn’t as im not sure this problem would have been so aparent on a road setup..

The problem is the car performed quite strangly and power tailed off fast at 5k for some reason.. I know it’s impossible to do a proper diagnostic just by looking at the graph but has anyone seen anything similar and might have some suggestions as to what is wrong?

Its was holding boost, fuelling was ok it just seemed to hit a brick wall at 5k for some reason as if it couldn’t shift the air, Chris thought that perhaps the exhaust was at fault, im going to try another but does anyone have any other options? Im going to double check the cam timing also..

Lets discuss

Should add spec is dark greens, T34, pace intercooler, mongoose, cone filter

 

A mongoose will cope with this power easy, so unless something has come adrift inside ?
I would certainly look at cam timing(possibly retarded), but if a worn dizzy they can be repaired, some pick up the top bush and spin it inside the housing as mine did, I had a gap of 0 - 2.3mm!!
Odd thing was the ONLY tell tale sign was a 1/2 misfire in REVERSE only,(due to revs being genrally lower I assume).
There is no way you WON'T feel this on the road, very bad it is, what is more important as a clue is what the missions were doing at this point ?
tabetha

 

The thought was perhaps the baffle in the backbox had come adrift and was causing an obstruction.. The dizzy is being repaired by a good friend of mine and should be ready to go back in shortly, I also had a slight misfire on certain runs which was put down to the dizzy wear.

My thought is the cam timing to be honest, Chris had to adjust the exhaust cam to make the 310 as it was out a little and the car only made 280 before this was done! I have verniers so it’s not plainly obvious whether its spot on or not. The emissions were fine as far as I know when the power dropped off.

Cheers Tabs

 

I am not being funny but this is exactly what a rolling road is for, things like cam timing swings to best effect, what cams are you running ?
tabetha

 

standard cams, yeah i agree but they didnt want to risk it not knowing valve clearances etc

 

why not try putting std cam pulleys back on and re timing it and trying again, also IIRC you can check the timing to std by taking the bolts off your vernier pullys and looking at the positions of the woodruff keys on your cams they should face directly away from each other on a horizontal plain when the bottom pulley is set in the cam timing position

 

I'd be looking at timing, why could TOTD not suss it out mate? Or did you not want them to cos of cost?

 

They did remove the pulley bolts and check the reference to the woodruff keys, but it’s not quite as easy to tell whether it is 100% spot on when they are apposed to each other. The Exhaust cam was out when we started and we adjusted it, but the inlet looked roughly spot on. I think I am going to have to do what Trev suggested and put the standard pulleys on then lock the cams and swap back to the shiny ones haha