Judgement day(s)

A litre of petrol only weighs 0.74 Kg, so I am sorry to disapoint but 13.5 gal only equals around 45Kg, not 61 as it would if it were water. After playing with race cars over the years I have found weight is very easily added but much harder to remove, particularly when rollcages, larger brakes, wheels and tyres are added.

So petrol only weighs 3/4 the weight of water? You learn something every day!
To the rolling road batman!!!!

So far so bad.......135bhp at the wheels!!!!!!!!! I am about to refit the standard injectors and go back....the guy at the RR says he has never seen a car running so rich and the power figure is so low because of it The good news is it pulled 240lbft of torque and will pull more when back on the standard injectors.

[simontaylor]

I've always been told that torque is more important than bhp, so not too bad, 240 ft-lb against a standard 214, but only a 12% increase don't sound too good. Good luck with the other injectors.

..yes, but the problem is if you put a standard GTA on the rollers, it will never hit 200bhp and 210lb ft of torque, its more like 185.

Well, the final results......194bhp and 242lbft of torque with 20% correction for drivetrain. Not what I was hoping for! It would appear there was a crossed wire when I advanced the igntion and Ive actually retarded it so that will account for some of it, although I'm not sure by how much. The guy at my garage reckons the RR must be suspect as he reckons on a turbo car the torque and bhp readings should be more similar. Oh well.....theres always next time!!

The power and torque figures should be closer together - but not because its a turbo. 21 Turbo's make massively more torque than power but thats how there set up. With standard cam timing if your just running more boost the curves should stay the same shape but just go higher. If your making 242 ft/lbs I reckon with the ignition timing sorted it should be about 225 bhp. It will probably increase the torque too though so my guess would be about 240/260 at 16psi of boost. Cars produce more power with a lean mixture but run hotter. What boost are you running? Also the duct running to your intercooler maybe hampering rather than helping as the design of the rear spoiler is for the air to flow downwards thru it so you may find its not flowing too well. Also what were the fans like at the R/R as you may have had very little air going to the intercooler. And although the EVO might have a similar power to weight ratio it will be quicker because it has a much wider power band. GTA's effectively have a 3 - 6000 rpm power band whereas most of the japanese stuff comes on boost 3 -3500 revs but goes to at least 7500-8000 revs, giving a 25% wider powerband. And if cars with the same power to weight ratio have widely differing power outputs the more powerful car is always quicker. Try racing an Elise from 40mph upwards in a Scooby with the same p:w and you kill it. And one last thing Skyline weights vary alot from model to model - the GTR's are 1480, 1540 and 1560 for the R32, 33 and 34 respectively.

The ducting to the intercooler comes in at each side so shouldnt be a problem, Ive also got the fan blowing in from the side and the water spray. The RR had a fan at the front and set one up at the rear to blow onto the intercooler so cooling wasnt a big problem. Ive had a fairly lengthy chat with David about the RR readings and they appear to be about right as torque peaked fairly early at 3000rpm and then was roughly the same as the power higher up the range. First thing to do is reverse the ignition problem. Dont know wether I'll have time (or money!) to go back to the RR before the season starts.......but for all the figures it still feels damn quick in a straight line.....with the igntion suitably sorted it should be quicker still. Need that programmable ECU to really sort it out!!

Well Ive reversed the ignition problem and the car now has at least another 100bhp ....seriously though it does feel noticably quicker.....burned off a 500cc bike on the way back home this afternoon!!!

have you got an adjustable fuel pressure regulator to run and fine tune the larger injectors?

No...hence why they are now back in their box waiting the arrival of the (fabled!!) programmable ECU........how is it coming along David??

Its getting there Pete. The new ecu requires 3 sensors from the R25 range which are more accurate than the GTA ones, air, coolant and throttle position, but Im having batches of billet aluminium adaptors made to fit them as they are smaller than the original sensors. Ive already had a play with the new ecu with out the sensors connected, and Its all fairly straightforward...Whats good is even though you can individually adjust every point in the map for fuel and ignition, on the main window you can shift the whole fuel and ignition maps up or down any amount, so if you fitted large injectors but wanted it to fuel correctly, you could shift the whole fuel map down say 10%, or you can advance the whole ignition system a few degrees by clicking the mouse instead of burning you hands behind the turbo trying to play with the TDC sensor!

How much did you move the sensor this time?

Only just past (advance!!!!) where it started from...maybe 1mm.....no more. As I said the car feels noticably more sprightly and pulls better at the top end.

I dont know if this will help you Pete, but as youve stripped the rear of your car, you could consider cutting a small hole about 6" x 6" in the rear fibreglass bulkhead behind the rear seats, but in line with the TDC sensor, so you could adjust it easily from inside the car. You could then make an oversize removable panel then to cover the hole back up.

Only just past (advance!!!!) where it started from...maybe 1mm.....no more. As I said the car feels noticably more sprightly and pulls better at the top end.

Any difference off boost..? Easier pull away?