AdamR Posted March 23, 2013 Author Share Posted March 23, 2013 Thanks to all who commented, I'm glad my wall of text was somewhat interesting! Obviously I'm still to drive the car, but will report back when I have done so. Paul - that's a good question, and one I don't know enough about to answer with any sort of conviction! My guess would be something along the lines of the estimation being relevant to the power of the car (i.e. a different correction factor being applied to a differently-powered car), or that the numerical amount of loss increases with the load on the drivetrain and therefore it is largely proportional to the power the engine puts out? Edit, just did some reading up and my first supposition is fairly true due to my second supposition. However, drivetrain loss for a Westfield (given the layout of the engine, drive shafts and diff) seems to be more like 10-15% from what I've read. Most of that is down to the diff having to change the path of the torque by 90 degrees apparently, then a couple of percent from seal drag, friction in UJs and the gearbox. The points raised put the loss in terms of kilowatts and therefore heat - if the losses were 25%, say, at 200bhp you'd be boiling fluid and melting housings apparently! I guess this goes to show that power at the hubs is the real figure to look at (which is how Blink work) and a 10% increase is significant regardless of the actual figures I'm more happy with the new shape of the torque curve and the improved AFR than the actual numbers though to be honest. Quote Link to comment Share on other sites More sharing options...
BLiNK Motorsport Posted March 24, 2013 Share Posted March 24, 2013 Just one query, how the heck does a transmission loss equate to a percentage of the power? My point is, two westfields, both with exactly the same gearbox and diff ratios have wildly different horsepower figures, the x flow car has 100bhp at hub, the duratec has 250bhp at hub, yet if a percentage calculation is used to get a flywheel figure, then the duratec as over twice the transmission losses from the same transmission..... Paul; see here - http://forum.wscc.co.uk/forum/index.php/topic/100347-rolling-road/?p=1033461 So, in other words you can't - it's just pure guesswork and is not an estimate of flywheel power in that vehicle but how our Dyno figures correlate to manufacturers figures if the engine was taken out of the car and placed in an ideaal test cell. It is just a guess and that's why we only print the Hub Power/Torque figures. HTH Quote Link to comment Share on other sites More sharing options...
AdamR Posted March 27, 2013 Author Share Posted March 27, 2013 That would have been a much better thing for me to post (the link), thanks for that! To continue from before... I had chance to nip out in the car this evening - the first thing I noticed was that the flat spot I had around 5800 rpm has definitely been reduced. Previously, in similar conditions (very cold, but dry), the 'jerk' in torque would have the rear tyres squirming (or worse) but now the car feels much more driveable with the smoother power delivery. The overall power didn't feel (on my bum dyno) to be vastly increased but I knew it must have been due to the results of the dyno runs... however, comparing some data from before and after the tuning session tells a pretty different story. My 'standard' test is an in-3rd-gear 60-90 run (that's all I have space for on my private road and I think it's a fairly 'real-world' test too), which was previously around 3.7-3.8s. With virtually identical ambient temperature and road conditions as before (dry but bl**dy cold), and averaging two runs in opposite directions of the same piece of ground, it appears to be half a second quicker than that! Incidentally the power calculator built into the software estimates the car to have 213bhp at the rear axle, and BLINK's dyno said 211bhp - pretty surprised the software is that accurate but I'm not complaining! Apparently it can be used to check if a car is down on power by comparing 'old' to latest data, which is a handy thing to know. Cheers, Adam 1 Quote Link to comment Share on other sites More sharing options...
AdamR Posted June 4, 2013 Author Share Posted June 4, 2013 Bit of an update, part 2 of the transformation has now been completed The first session in March was to make the car safe at full chat (it had previously been too lean), which was successful, but Richard and Fraser weren't happy to leave it at that. So, I popped back this morning to run through the rest of the map and see if the dry sump system I'd fitted recently had freed up any power. The theory is that because the crankcase runs in a slight vacuum (two stages of the pump 'scavenging' from the engine but only one pushing oil back in), the windage losses from the crank hitting the air and oil froth in there are reduced, so the car can make a bit more power. Naturally we left the power runs to the end Last time I managed to melt their floor paint and a rear arch had to be removed to get the car hooked up However, they have since made an exhaust outlet and some huge hub adaptors - top stuff! So - onto the mapping. It turned out the fuelling was a bit ropey mid-range and on part throttle, with some areas too lean and others too rich! But, after some adjustments (made easy by the Dynapack being able to hold the car at a steady rpm while the throttle was opened in stages) the AFR was corrected throughout and a bit of pinking / detonation at high throttle and low revs removed. This should improve driveability / smoothness and fuel economy, too. The torque plot is certainly smoother now which I was chuffed with! A couple of runs with the car held at full throttle at 6500, 7000 and 7500rpm were done too - bl**dy scary watching that - to ensure the mapping was spot on at these commonly-used, high-stress areas. Finally, we did a couple of power runs, Richard tweaking away between each one to fine tune the AFR. Turns out peak power was up 6bhp at the rear hubs, and this sort of gain was pretty consistent from 6k upwards Nothing like the crazy gains some people claim from dry sumps (I've seen 20bhp!) but as a side effect of a better oil system I'll take that! I'll scan the graphs and pop them up later for anyone interested Quote Link to comment Share on other sites More sharing options...
FILFAN Posted June 4, 2013 Share Posted June 4, 2013 thats about 5% increase and nothing to sniff at all good sorry to sound smug though but when they first announced they had a dynapack i said straight away that they needed extensions to fit a westfield on due to the limited clearance as my car was tuned on one and ran into the same issues. never got any response Quote Link to comment Share on other sites More sharing options...
AdamR Posted June 4, 2013 Author Share Posted June 4, 2013 thats about 5% increase and nothing to sniff at all goodIt's a bit less than that for my car (up to 217bhp from 211bhp at the hubs), but still, all good as you said! Makes sense - maybe they were too busy dreaming up how to fix it, haha. Quote Link to comment Share on other sites More sharing options...
FILFAN Posted June 4, 2013 Share Posted June 4, 2013 what you done to the engine Adam is it just cams or you got some headwork done 1 Quote Link to comment Share on other sites More sharing options...
AdamR Posted June 4, 2013 Author Share Posted June 4, 2013 I haven't done a lot other than fix what other people did wrong and get it mapped properly, but the spec is something along the lines of...- Standard crank- Standard head (was sold to me as CNC ported with oversized valves )- Simpson full exhaust system- 48mm ITBs- Peco 480 injectors- SBD 295 cams- Double valve springs- Titanium valve caps- Ultra light weight cam followers- Vernier pulleys- Oversize pistons (86.5mm I think)- Steel rods- Ultra light flywheel- Twin plate paddle clutchSomeone has spent a few quid on it Quote Link to comment Share on other sites More sharing options...
FILFAN Posted June 4, 2013 Share Posted June 4, 2013 ooo giving me ideas were on pretty much the same spec other than cams.must get my cams in soon they are on the shelf waiting to go in though they are not as agressive they should see me about 180-190 at the wheel. just need to modify my rocker cover to mount a cam sensor first Quote Link to comment Share on other sites More sharing options...
AdamR Posted June 4, 2013 Author Share Posted June 4, 2013 Sweet - should give you a decent power hike then Although having the car off the road during decent weather is a bit of a bummer... Quote Link to comment Share on other sites More sharing options...
FILFAN Posted June 4, 2013 Share Posted June 4, 2013 oh there is no rush it can wait til the winter 1 Quote Link to comment Share on other sites More sharing options...
AdamR Posted June 5, 2013 Author Share Posted June 5, 2013 Managed to get the two graphs scanned in to compare, the greyed out lines are the 'before'... Quote Link to comment Share on other sites More sharing options...
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