gerg 10,871 Posted February 24, 2015 It's not about needing to be rich, rather the extra fuel injected stabilises combustion and keeps it on the "safe side" of detonation. You could substitute the extra fuel with water if you wanted (ie water injection... What a great idea) Share this post Link to post Share on other sites
PRO250 1,506 Posted February 25, 2015 Im no pro on boosted either but all my boosted stuff the old XR and turbo corty I ran them ritch you use the fuel as a cooling effect as the boost rises it keeps the cast pistons from melting most of the boosted suff of people around me you flash them onto boost they will peg fuel everywhere and those engine don't kill the pistons all the others do unless there forged, but even thenLook at my white car not on fuel and cause the gas is a dry it burnt a piston and broke a ring on a super safe tune with no timing turbo corty on the same boost level is still around and with 4 degrees more timing and the same boost level but on fuel and ritch as Id look at valve springs, mine where 130 on the seat and 350 open in the end to keep the valves shut. Pull 1 out and check it id do this before wasting money on anything else, if its not the issue check cam timing or just go bigger Share this post Link to post Share on other sites
Xelisty 366 Posted February 25, 2015 Yes rich but I had no clue until I saw that. The car feels strong and fast for what it is. Cracks a sub 6 sec 0 to 100. Where so you draw the line with tune safety. It's not a race car but street. It was tuned in Brisbane in 20-25 deg days with low humidity but they knew it was to be used in darwin 35 deg heat and very high humidity and I said I plan to take it down the strip. He knew there was no local tuners and he did not want anyone messing with it as he set it up for me. (although there may be a tuner but none have been found to date) It drives great, does not blow smoke so no negatives that I can see. Been over 12 months and 5-6000 km. Interesting though but really nothing can be done without retune. Thanks for the great advise all round . Happy for further discussion and thoughts Off shopping for the below over the coming months. I will get further advise and take it slow to ensure all correct. Bit of copy blatant copy from people but a idea anyway the way the car will head to progress Find tuner to assess currect set up, afr, retune for local conditions etc. Go shopping 1. Automotive boost referenced fuel regulator (rising rate, what ratio) 2. Wait until the T5 blows and get a supra box 4. 28 spline axle upgrade (where do you get these and what else is needed. My LSD is very tight and totalled rebuilt) 5. Aeromptive 340 intank pump or similar 6. 1000cc injectors , matched set 7. High flow fuel rail (assess) 8. CDI msd 6a ignition and misc components, coil etc. 9. Roller cam and chain, 10. Billet hydraulic turbo cam 11. Roller rockers with raised tappet cover 12. Ported alloy head, port matched exhaust and inlet 13. Tune and dyno (find tuner) 14. Maybe clutch Other Bigger radiator (with thermos fitted ) Upgrade alternator 90/10 front shocks (new rears already sorted) Remove front swaybar Rear sway bar large Start buying forged internals Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
Xelisty 366 Posted February 25, 2015 The valve springs are brand new. First thing I did. Psi double Good top spring quality. Tuner first though and see how we go Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
XPT 673 Posted February 25, 2015 Really - I would have thought that it would have been the same. If anything the more fuel would be bad for the turbo as it would be increasing the heat in the charge and making it spool harder. I know the 'anti-lag' on the autronic dumps fuel and reduces timing to give the turbo a hot charge to help it spool up. why the difference for a Turbo engine in afr? My turbo knowledge is limited - that's why I am building my turbo crossflow project. When I had the Supra tuned the tuner aimed for 11.5 AFRs he told me that with an XR6T he would aim for about 12:1 AFRs due to the more modern and obviously better head design among other things. I don't know where the xflow efi heads rate in comparison . The 7MGTE is 8.4:1 comp and both the Barra and EFI 250 are 8.7:1 comp, where this places the XFlow as far as a safe AFR I'm not sure, but you would imagine 11:1 AFRs would be safe Share this post Link to post Share on other sites
PRO250 1,506 Posted February 25, 2015 You will find being at the smaller sized cam the matched spring pressures will be very low, under 290 on the nose. That's the first place id look if it was my boosted crossy, my springs where 110 and 280 on the nose and would not keep up after 7psi of boost it costs nothing to check its installed hight and open or 500 thow pressure, then pull a spring on the intake and exhaust and take to a machine shop and ask them to look at it at your measurement you have takenThis is something so many people over look in a engine and is one of the biggest reasons you see strong engines that will not pull or will not rev. I can only advise you and i can understand if you had to spend coin but this you only have to spend 15min of your time and a trip to the machine shopIts your car and it up to you how you go about it. but with everything you run is on the large side of things this is where id look first and then cam timing and cam size the next Share this post Link to post Share on other sites
Xelisty 366 Posted February 25, 2015 Done. I will get Danny to check next week the valve think you mentioned. . I will let you know. Btw I have no clue what you are talking about with the spring pressure but Danny will and that what matters. Cheers Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
ando76 4,354 Posted February 26, 2015 A standard - unported xflow would be crap when compared to the Barra. Think there is some data on that in the crossflow porting thread. A well ported x flow head will run with the barra heads. I would think that somewhere between 11.5 and 12.5 would be fine - when tuned in Darwin conditions. It seems to me that Mike may have overcompensated for the heat and humidity - better to be safe then hole piston sorry. I love this graph from Toyota - I reckon it is a valuable tuning guide for all. 2 Thom and gerg reacted to this Share this post Link to post Share on other sites
Xelisty 366 Posted February 26, 2015 I have zero interest in a barra. I could of got a xr6 turbo for less than the xe with all the turbo kit. Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
Xelisty 366 Posted February 26, 2015 The car is heading to the shop next week to get some checks done a fuel surge tank. I just don't like the idea of changing to a late model engine. For me that is. Lots cheaper power chucking a barra in I know. Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
ando76 4,354 Posted February 26, 2015 Yeah mate stick with the crossy. I love em. Barra engines are nice but I'm old school - love my pushrod dynosaurs. Bahaha Share this post Link to post Share on other sites
XPT 673 Posted February 26, 2015 Xelisty I wasn't suggesting for a second you swap for a Barra, not after you've gone this far. I was just giving a comparison from what a tuner told me about AFR's and what he considered safe for a modern turbo engine, compared to a more old school engine A standard - unported xflow would be crap when compared to the Barra. Think there is some data on that in the crossflow porting thread. A well ported x flow head will run with the barra heads. I would think that somewhere between 11.5 and 12.5 would be fine - when tuned in Darwin conditions. It seems to me that Mike may have overcompensated for the heat and humidity - better to be safe then hole piston sorry.I love this graph from Toyota - I reckon it is a valuable tuning guide for all.Ando- I wasn't so much talking from a perspective of flow because the answer is obvious, more chamber design and detonation threshold. This is a stock head If I remember right, you would know a lot better than me about which heads have the best chamber shape from factory. Would this be an E1 head? Share this post Link to post Share on other sites
ando76 4,354 Posted February 26, 2015 Yeah me too - I wasn't suggesting a Barra conversion - we were just talking tuning comparisons. XPT - My personal opinion would be the E2 head as it has the smallest of the open chambers and also better valve sizing. That is what I have on my forged 250 rod turbo motor. It also does not have any 'sharp' points like the C1, C1A, C2 and D heads. I know we all remove those sharp points on the valve shrouding on those heads but I think the E2 is better and with a bit of shave you get them down to 47cc pretty easily which is where most de- shrouded C/D heads end up anyway. In my experience those sharp points can be a real detonation hot spot, pun intended, so not having them would be a good thing in the turbo application. 3 XPT, Thom and Outback Jack reacted to this Share this post Link to post Share on other sites
Xelisty 366 Posted March 28, 2015 Progressing on this. Springs have been measured. I don't have the numbers yet but the mechanic has. Maybe a tad soft he thinks but the details are with crow cams for feedback on what suits the cam. It's Going on the local dyno early this week to do some runs and checks. Got a number of other things done while there like fuel surge tank set up, new drag spec shocks, shift light, tailshaft hoop and few odds and ends. Once I hear more I will update. Sent from my iPhone using Tapatalk 7 ricktewagon, Thom, NZXD and 4 others reacted to this Share this post Link to post Share on other sites
Xelisty 366 Posted March 31, 2015 Got some info.. Dyno bloke and specialist said all is well. All in the timing. It's correct and set to do what it does and power is where it is supposed to be. No other limiting factors. He says basically seems set to protect the stock engine. I will get the new dyno print outs up soon. It has boost on it too, afr etc. Springs were all tested with even result of 110psi at 48mm at fitted height. In the range and well adequate by crow cams. Oil pressure correct at 45 psi at idle and 70 at 3000rpm so not too high to cause issues. So drags on Friday night on a beat the heat night. Pretty popular those nights. No changes so still mid to low 13s I guess. Sent from my iPhone using Tapatalk 1 wagoon reacted to this Share this post Link to post Share on other sites
Xelisty 366 Posted April 7, 2015 Dyno sheets below. Seems the afr are where they should be. Maybe the above dyno was done on earlier runs at mvt. Either way seems ok Electronic boost control so no big whammy in the middle. Looks good Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
Xelisty 366 Posted April 7, 2015 The revs I estimated were out a bit too. Seems to make good power up to 4250 and hits the limit of something as power drops big time. For a crossflow with big turbo reasonable really Thoughts? Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
NZXD 2,328 Posted April 7, 2015 It seems to make decent power at low rpm, it doubles its power between 2250-3500, and 300rwhp is pretty decent. Share this post Link to post Share on other sites
ando76 4,354 Posted April 7, 2015 Just commented in the other thread. The answer is right there in the AFR reading. Look at the dip in the power curve between 3750 and 4500. When it goes rich at 3750 the power drops off and it never recovers. It needs less fuel as it is killing it. clear as day to me. It should be sitting at 12.3 the whole way through in my opinion. if that happened it would continue to make solid power and torque. Would love to see the torque graph overlaid with the AFR. Betcha I know what is happening there. 1 Outback Jack reacted to this Share this post Link to post Share on other sites
TUFE 284 Posted April 7, 2015 didnt this get detuned to protect the driveline? Share this post Link to post Share on other sites
Xelisty 366 Posted April 7, 2015 Good point. No torque graph. I will chase up and hopefully they have it still. I will ask for the overlay with afr. Tufe, yes correct. T5 was a risk and stock internal. Reliability was critical Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
ando76 4,354 Posted April 7, 2015 well that's what he has done. killed it with fuel to save the box id say. Piss the t5 off and go to a single rail, much stronger or better still auto with a stall and then pull the fuel out of it and hold on. 1 Outback Jack reacted to this Share this post Link to post Share on other sites
TUFE 284 Posted April 7, 2015 If its stock internally, that stock engine isnt far off maxxing its potential power output. Not to say it couldnt make a stack more(because it would). But ive always been told ~250rwkW is a good figure to work with. Any more and you'd start looking at spool or 200 rods. My 2c Share this post Link to post Share on other sites
ando76 4,354 Posted April 7, 2015 I'm not so sure on ^^^^ that. Really the piston and rods are still travelling at the same speed (RPM) whether the tune is spot on or not. So therefore the load on them does not change. I actually think that over fuelling it would be causing more load on them. Its not like he is trying to turn the engine harder - its just that the power is falling over because of the tune in my opinion. I would think that this engine would be fine to 5500 with stock gear and the current boost level. It is very obvious that Mike Vine - who is no dill - has tuned this package to protect the current drive line. Shifting at 4500 would be putting a massive load on that box. Look what the torque did to the old pinion yoke. Share this post Link to post Share on other sites
Xelisty 366 Posted April 8, 2015 True. Good sound though. Fkn crack!! I have not revved it hard on launch since. 17 apr I will get on it a bit harder... Sent from my iPhone using Tapatalk Share this post Link to post Share on other sites
