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Old 26th September 2012, 06:28   #6
Sandy309
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Join Date: Jan 2010
Location: Cornwall
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Alot of the JRE engines I map on our engine dyno go to Steven Gault's rolling road once fitted in the cars over there. I know how the figures for those compare.

The last engine I dyno'd in this spec (engine dyno, DIN corrected and calibrated, not to be confused with the vagueness of rolling road figures), was almost identical to Josh's, the only significant differences were Jenvey SF bodies on my own manifold (same tract design effectively as Josh's) and the same geometry exhaust, made by a different fabricator. Peak figures were 234bhp at 8500rpm (as far as I tested it) and 159lbft at 6500rpm, with two slightly different inlet configurations. I tried alot of different injectors and injector positions, cam timing etc to arrive at this, two days of dyno testing on an engine I've already developed extensively.

Here are the figures for two inlet tract variations I tried (these are the stable recorded steady state figures plotted on a simple Excel spread sheet):


Pictures of that engine on the dyno, showing some of the inlet/injectors variations I was testing:






Pics capturing the readout (DIN figures are what matter and ignore the Lambda display, we were using a separate one), believe me it was quite an emotional moment when I saw 230bhp+ for the first time!




Before everyone gets too carried away with peak or wide open throttle figures, I should point out the range of other qualities I have achieved with these engines that I'm proud of and I feel makes them stand apart from others... Driveability (they are totally road friendly and little need to be revved to perform), economy, no oil or water leaks even after a couple seasons, negligible breathing and oil consumption, so far total reliability and aside from the glitch with Josh's fuel system, after I've trimmed the map in the rollers and/or on the road once, that's it, they run sweetly until the next rebuild.

I regularly dyno other people's race and rally engines of similar spec that customers have paid in the region of £13-15k for and don't perform anywhere near like this. I haven't got a set price for this spec, because individual builds always have a certain amount of variation, customers have an ECU already etc, but from scratch, with OE crank, exhaust manifold, ECU+loom, race clutch and steel flywheel, dyno'd and ready to use, it's about £11-12k. I do limit my builds, because of the other ongoing commitments I have (about half of my work is mapping, wiring and development for other engine builders; also the need to do scheduled work on existing engines) and currently the waiting list is well into next year so I'm afraid I can't really consider doing any more just now.

Last edited by Sandy309; 26th September 2012 at 06:37.
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