Ian C Posted July 8, 2003 Share Posted July 8, 2003 I just finished installing an EGT gauge in the car and took it for a test drive. Chris Wilson installed the probe for me yesterday, it took him, get this, 53 minutes flat (not that I was timing him or anything ) and it did involve some dismantling in the engine bay which I didn't dare watch. As ever, mucho thanks to Chris, job well done, good chat and good cuppa afterwards as well So here, for reference if anyone wants it, is the results: Car setup: Hybrid sequential twins FMIC with some shonky ducting 550cc injectors Walbro/CW fuel pump Apexi AFC, set up 'safely rich' by CW Apexi pod air filter with shonky heatshield Vented bonnet louvres and no underbonnet insulation CW double decat pipes with Apexi back box CW restrictor ring Fuel: Shell Optimax Boost pressure: Running a maximum indicated 1.31bar of boost at the manifold, normally holds around 1.25 though. Ambient temperature: 18degC Idle: 320degC Tootling around: 500degC 80mph cruise: 700degC 110mph cruise: 780degC WOT in 6th on first turbo: Between 700 and 800degC WOT in 6th on both turbos, up to a true 168mph: 880degC maximum All done on my private test track, of course. I'm relieved to see that my EGTs are all well within safe parameters despite giving it serious abuse on a warm day -Ian Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 8, 2003 Share Posted July 8, 2003 Hello Ian, So those EGT tempratures of yours a fine then??What is a limit approaching max temp for the manifold?? How come you do not run higher boost.....just curious mate? Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 8, 2003 Share Posted July 8, 2003 O h and another thing, you are fully decatted, is this ok with hybrids?? Link to comment Share on other sites More sharing options...
Sharpie Posted July 8, 2003 Share Posted July 8, 2003 Ian, Nice to see those numbers I get the same at BPU on stock twins. 820 at WOT (1.25bar) and have only ever been to 880 once on a very hot day with a fat bloke riding shotgun. CW put in my probe too. u_ali, I have 900 set as my warning and upto 950 is fine depending where your probe is located. Link to comment Share on other sites More sharing options...
Doug Posted July 8, 2003 Share Posted July 8, 2003 For reference mine recorded 850c max at WOT on my stock car with both cats in. Leon installed my probe, not sure exactly where, might have to check to ensure we are getting a fair comparison. Link to comment Share on other sites More sharing options...
Ian C Posted July 8, 2003 Author Share Posted July 8, 2003 950degC is about as high as you want to peak, you don't want to run that all the time I too had a fat bloke riding shotgun, he was taking some film footage using a digital camera, no sound but suprisingly good quality. I can't believe how quickly the speed ratchets up, it's different when you are driving hard as it's 95% road, 5% rev counter so I never notice the speed factor. Just watching the Apexi digital readout now, it takes about four and a half seconds to get from 77 to 107mph in 4th gear, tee hee. I have a double decat, yes, trouble is it boost creeps, hence the restrictor ring. I'm going to take it out as a test, I'll see what happens to the EGTs using the throttle to hold the same amount of boost, and then at WOT to see what boost levels and EGT values I get. Theoretically, the EGTs should go down without the restrictor ring in as the whole system is freer-flowing, but then if the boost creeps up it will bring the EGTs back up again simply due to more exhaust gas being generated (and more power, hopefully, woohoo!). I'm going to be careful as it should show the limitations of the sequential setup, which should be of interest to folks here It's interesting to see that roughly the same values are recorded on stock engines, those CATs must really hold in the heat/restrict the flow! Also, the cooler the intake charge, the cooler the EGTs, so the big FMIC, it's ducting, the pod filter heat shield, and the vented bonnet must all add up to the thankfully respectable results. My probe was located in cylinder 1's exhaust manifold runner by the way. -Ian Link to comment Share on other sites More sharing options...
Sharpie Posted July 8, 2003 Share Posted July 8, 2003 I have a FMIC going on at the moment so, will look at the difference next week when I get her back. Yeah, I would start watching things very close indeed, if things get over 900. I have not been on a track yet so, can not say what they would be like..... No cats here Link to comment Share on other sites More sharing options...
Guest Terry S Posted July 8, 2003 Share Posted July 8, 2003 Ian the EGT's get really high on the transition between #1 & #2. When #2 is on line I never saw more than 800. Hold it at about 3800 rpm & you'll see what I mean. Link to comment Share on other sites More sharing options...
Ian C Posted July 8, 2003 Author Share Posted July 8, 2003 I saw yours up on the ramps Very nice and clean! I've been reviewing the footage frame by (blurry) frame and have found that 4th gear was running 1.2bar of boost, 5th went to 1.24 and dropped to 1.21, and 6th ran from 1.30 to 1.28bar. So 4th and 5th need a touch more duty cycle to get them to 1.3bar, heh In answer to u_ali's question about why I don't run higher boost, it's because I don't need to Safe fuelling, safe EGTs, and a nice moderate boost pressure. Although I will try it a bit higher to see what the results are. I have plotted the speed increase over time off this video so I can check if extra boost actually makes it noticeably faster -Ian Link to comment Share on other sites More sharing options...
Ian C Posted July 8, 2003 Author Share Posted July 8, 2003 Originally posted by Terry S Ian the EGT's get really high on the transition between #1 & #2. When #2 is on line I never saw more than 800. Hold it at about 3800 rpm & you'll see what I mean. I remembered you telling me that ages ago, which is why I gave it WOT in 6th at about 2500rpm. The EGTs didn't reach beyond 800degC, but I didn't *hold* it at 3800, I'll try that as well. Was your probe in the manifold runner as well? And was this when you were running 1.6bar on race fuel? -Ian Link to comment Share on other sites More sharing options...
Barry Posted July 8, 2003 Share Posted July 8, 2003 Ian, Where is the EGT probe, before or after the turbo's? Link to comment Share on other sites More sharing options...
Ian C Posted July 8, 2003 Author Share Posted July 8, 2003 Cylinder 1's Exhaust manifold runner. Well before the turbos. -Ian Link to comment Share on other sites More sharing options...
Barry Posted July 8, 2003 Share Posted July 8, 2003 Gottcha.! Link to comment Share on other sites More sharing options...
Alex Posted July 8, 2003 Share Posted July 8, 2003 Glad to see there was nothing to worry about, get that restrictor out and the boost up and get on down to 10OTB2.... Just remeber... There is NO TIMING GEAR! Link to comment Share on other sites More sharing options...
MONKEYmark Posted July 8, 2003 Share Posted July 8, 2003 after fitting fmic my egt`s went down a bit. have had it in ttc mode and they have gone a bit higher almost hit 1000 on hks electronic egt with probe in same place chris fitted mine. have put back in sequential now and will keep an eye on them at elvington on sunday. back to a steady 1.1-1.2 bar now other day in ttc mode hit a high of 1.45 bar going to get mine sorted after sunday, get some fueling mods as i am stock jap fuel system. water injection is going to be needed too. hope you do well at 10otb2 Link to comment Share on other sites More sharing options...
Guest Terry S Posted July 9, 2003 Share Posted July 9, 2003 Ian the probe was in the same place. No idea when it went as at first I assumed the EGT gauge was faulty. I am starting to wonder if I had a faulty VSV which was causing #2 not to come on line properly, hence the high readings. I could watch it hit 950 then drop back to 800 as soon as #2 was fully on line. Link to comment Share on other sites More sharing options...
Digsy Posted July 9, 2003 Share Posted July 9, 2003 Nice work Ian. On a completely unrelated note, there was a very sneaky speed trap on the A11 yesterday Link to comment Share on other sites More sharing options...
Gaz Walker Posted July 9, 2003 Share Posted July 9, 2003 Originally posted by Darren Blake On a completely unrelated note, there was a very sneaky speed trap on the A11 yesterday Don't think he wanted to know that! Gaz. Link to comment Share on other sites More sharing options...
Ian C Posted July 9, 2003 Author Share Posted July 9, 2003 Thankfully I used my secondary backup test track, Alpha-47. If only they knew what they missed -Ian Link to comment Share on other sites More sharing options...
Nathan Posted July 9, 2003 Share Posted July 9, 2003 Originally posted by Ian C WOT in 6th on both turbos, up to a true 168mph: 880degC maximum Good data Ian. Nice one. If only to explain why I wince when I hear of Jap specs running 1.25 bar with stock pump, 440cc injectors and no AFC....... Did you do a duty cycle check flat out at 168mph? Makes interesting reading.. Regards, Nathan TDI PLC Link to comment Share on other sites More sharing options...
Ian C Posted July 9, 2003 Author Share Posted July 9, 2003 I didn't, no. I wouldn't know how to. The Apexi unit has an injector duty cycle readout but I think it doesn't actually bear any resemblance to reality so I've switched it off Shouldn't be running too close to the limit. AFC wouldn't help much on stocker injectors -Ian Link to comment Share on other sites More sharing options...
Alex Posted July 9, 2003 Share Posted July 9, 2003 Could you not wire up an injector duty cycle read out using just a Multimeter? As long as you tap the source between the injectors and the electronics? Link to comment Share on other sites More sharing options...
Geezabloke Posted July 9, 2003 Share Posted July 9, 2003 I was talking to someone yesterday about EGT probe locations? I was informed that he likes to fit the probe in the down pipe as he has had probe disintigrate before and this could cause damage if any bits went through the Turbos? Sorry if this sounds utter tosh to some? But ive got an Apexi EGT on route and am wondering where the best location for the probe is and should i get an expert to fit it? If so whats the approx cost of fitting just the probe in place? Cheers Guys Link to comment Share on other sites More sharing options...
Ian C Posted July 9, 2003 Author Share Posted July 9, 2003 After the turbo's is apparently worthless as they suck about 200degC out of the system, so the reading would be waaaaay off. Boy have I got some juicy info for you guys after further testing today. I took out the restrictor ring, and thanks to my stupid boost controller rumbling this change and reaching for the stars, I hit a gargantuan 1.57bar (23psi) in 6th at WOT. I only noticed this on the peak hold on the damn boost controller afterwards. I was watching the EGT gauge and it read a maximum of 940degC. So, conclusion 1 is that on my system a more sensible 1.4, maybe 1.45bar would be within tolerable EGTs. But keep reading. I switched off the boost control and let the stock system take over. This would open the wastegate at 0.8bar but the massive boost creep synonymous with hybrid twins meant I would get, eventually, north of 1.4bar, in fact in 6th I hit 1.5 at one point. This was on the way home, ambient air at 13degC, drivers window down again, two people in the car again, and videoing the Apexi digital speed readout again. Conclusion 2 is that without any boost control, I would creep to a maximum of 1.5bar of boost. OK then, so file out the restrictor ring a bit and put it back in to run at 1.4 or 1.45ish. But again, keep reading... I made a spreadsheet of the two test runs, recording how long it took to get from one 10mph boundary to the next, using video editing software to get it accurate to 1/1th of a second. So I knew, say, it took 0.9s to get from 60 to 70, and 1.4s to get from 70 to 80, including a gearchange. Here is the contraversial kicker, folks - I didn't go any faster. The times were within 0.1s on each test. So the difference between 1.2 to 1.3bar in test one and 1.4 to 1.5 bar in test 2 was a big fat zero, except my EGTs were higher and hilariously I popped a hose off the EGCV VSV at 135mph (and duly shat myself as the engine lost power ) The turbos are obviously at a point where the increase in charge temperature cancels out the potential power gains from the increase in airflow, so the end result is pretty much static. So, conclusion 3 is that the restrictor plate is going back in, the boost will run at 1.2 to 1.3bar, the EGTs will stay below 900degC and I'll be happy knowing I'm just as fast as if I was hanging the arse out at 1.5bar. Chris, Nathan, et al, you wuz right all along -Ian Link to comment Share on other sites More sharing options...
Ian C Posted July 9, 2003 Author Share Posted July 9, 2003 And Terry, I tried holding the revs at 3800 in 5th, and I tried going through the rev range at WOT in 6th, and all sorts of stuff, and I couldn't get #1 turbo EGTs beyond 700 to 800degC, so I dunno what was going on with yours -Ian Link to comment Share on other sites More sharing options...
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