exodus87 Posted May 22, 2023 Report Share Posted May 22, 2023 Currently I've been chasing this issue for about 2 months . I have gen 3 freshly built 2.1 stroker . Ct26/gt30 hybrid. 800cc injectors . 255 inline pump . Currently on a remote steet tune .Issues I'm having, throttle delay . When I accelerate there's a pause/ delay in the throttle. Car is very sluggish in any gear any rpm. And at WOT boost cuts at 5k rpms. Any info or help would be great mr2 new map 1 revised.pclx PC Datalog - 2023-05-16 9_18_21 pm boost cut.llgx Quote Link to comment Share on other sites More sharing options...
Adamw Posted May 22, 2023 Report Share Posted May 22, 2023 You have no accel enrichment as the cold correction table is zero'd out, the smallest value would typically be 1.0 in there at normal operating temp and 2.0-7.0 at the cold end depending on injectors etc. For the boost cut you likely have a short spike that gets too close to the limit, you will see it better if you ecu log at say 200Hz, but since you are hitting the cut you will either have to lower boost, raise the limit, or reduce the control range. exodus87 1 Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 22, 2023 Author Report Share Posted May 22, 2023 @Adamw I'm really a noob at this. I was expecting my tuner to know all this and tune it accordingly . If you wouldn't mind telling me what to do step by step to correct these issues i would greatly it. I see youre the goat on here for all issues . Much respect man . I set the dead times for my injectors (sard 800 sidefeeds) and tuner told me to run boost strictly from turbo housing to wastegate with no boost controller or tvsv til these matters get resolved Quote Link to comment Share on other sites More sharing options...
koracing Posted May 22, 2023 Report Share Posted May 22, 2023 If you're hitting MAP cut (set to 252kpa or about 22psi) with no boost controller - your "CT26/GT30" turbo is in dire need of porting on the wategate passages. Also verify there are no mechanical restrictions to the movement of the wastegate actuator arm as some aftermarket ones will hit the housing or arm, and some aftermarket downpipes can interfere with the movement of the arm. If your injectors are SARD 800cc side feeds - did you have them flow tested? Your tune shows them set as 850cc injectors. You're also lean on boost until you hit that cut which the accel enrichment should help a bit, but the base fuel table is off. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 22, 2023 Author Report Share Posted May 22, 2023 @koracing I have been think that it might be the wastegate actuator. I'll check today with hooking up compressor to open wastegate and see if it closes properly. My sard 800 were on my previous engine (gen 3 stock with ct20b) running apexi power fc . Never had an issue with them . Any edits i should do on the tune to try and fix some of the issues. Also while driving when I'm off throttle, afrs stay rich . Afr won't go lean at all. Thank you for the reply Quote Link to comment Share on other sites More sharing options...
koracing Posted May 22, 2023 Report Share Posted May 22, 2023 Yeah I'm not a fan of the internal wastegates on upgraded versions of the factory turbo. They often have problems. Where did your deadtimes come from? Were they verfied/checked in actual operation? The short answer regarding AFR readings is: it needs tuning. There are a lot of settings and if you have an agreement with a tuner who is providing these services, they should be helping address issues with AFR settings off boost even if the on-boost isn't fully controlled at the moment. Other things you should have set up in my opinion: -knock detection/control setup -Overrun fuel cut setup -boost control basics setup -IAT mode turned off -Charge temp approximation table set up -Asynchronous injection on -Wall wetting > 0 This is just based on my quick look over the tune thus far. Wall wetting compensation can help decrease how much accel enrichment is required. PS thank you for going away from the power FC and to something much more capable like the Link. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 22, 2023 Author Report Share Posted May 22, 2023 @koracing yes injectors were verified and tested on one of my previous tunes . And I'm regards to the additional set ups I should have done I suppose I'll speak to my tuner and hopefully he'll address those with finalizing the tune. It would do it myself if I had step by step. But as previously stated I know next to nothing when it comes to tuning . First and foremost I have to male sure that wastegate is ope ong and closing properly. Thank you Quote Link to comment Share on other sites More sharing options...
koracing Posted May 22, 2023 Report Share Posted May 22, 2023 So you verified your 800cc injectors flow 850cc? Strange. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 22, 2023 Author Report Share Posted May 22, 2023 @koracing yes 800. They are low impedance though. I didn't want to change the rail just yet. That's why I went with 800 . They only read 2ohms roughly. I know that's low unfortunately. But they worked great on the power fc. I was making 330whp until it didn't. Lol Quote Link to comment Share on other sites More sharing options...
koracing Posted May 22, 2023 Report Share Posted May 22, 2023 I don't think you're reading my words. 800cc injectors is what you have, but in your current tune they are listed as 850cc. Given the fuel model that is being used, accurate data is paramount. That difference doesn't seem correct to me. Low impedance isn't a problem with the factory resistor pack in place. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 23, 2023 Author Report Share Posted May 23, 2023 @koracingo shit . Sorry man. Yeah I don't know why my tuner has them in at 850 . They are 800cc. Is that something i can change or he would have to do it ? Quote Link to comment Share on other sites More sharing options...
ellisd1984 Posted May 23, 2023 Report Share Posted May 23, 2023 Sounds like you need a refund off your old tuner and use that money on a new tuner Quote Link to comment Share on other sites More sharing options...
koracing Posted May 23, 2023 Report Share Posted May 23, 2023 I think that would depend on how his tuner reacts to the suggestions here. If he is receptive to making improvements or changes based on this feedback, then I don't see a reason not to continue, particularly if improvments are made. If, however, he rejects any outside advice, that would tend to be a red flag in my book. Changing the injector size from 850 to 800 will cause the ecu to inject slightly more fuel (6% give or take), and so should be a relatively low risk proposition to do. If you're concerned about making changes, save a copy of your tune, then save a second copy with a different name, then make your changes and save. You can't have too many backups. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 23, 2023 Author Report Share Posted May 23, 2023 Can any of these issue be caused by timing being advanced or retarded . It was set at 10 BTDC . but I'm not sure if it jumped Quote Link to comment Share on other sites More sharing options...
koracing Posted May 23, 2023 Report Share Posted May 23, 2023 What makes you think your timing may have jumped a tooth? If you suspect your timing belt has jumped, and given the distributor is driven off of the intake cam, you not only run the risk of being off on ignition timing, but your VE will also be incorrect making any tuning invalid. Pull the upper timing cover and rotate engine over to TDC and see if the cams are lined up correctly before proceeding further. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 23, 2023 Author Report Share Posted May 23, 2023 @koracing I'm just pulling at straws at this juncture . I supplied air to the wastegate actuator with my compressor and flapper opened. However it opened pretty loud . I'll make sure to check the timing marks on the valve cover before I do anything regarding timing. In regards to turbo I am set up turbo house to wastegate . Waist gate should only be 7 lbs . I'm getting about 17 18lbs so it's definitely overboosting Quote Link to comment Share on other sites More sharing options...
koracing Posted May 24, 2023 Report Share Posted May 24, 2023 How far does the flapper move? It should rotate on the turbine housing 60-80° of travel. The arm should move about 1/2" if memory serves me. If that's all working right, you need to pull the turbo and port out the wastegate passages for more flow - or take it to someone to have it ported. Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 24, 2023 Author Report Share Posted May 24, 2023 @koracing I removed the e clip off the actuator and moved the flapper by hand and it seems to travel the distance it needs to. However I am using a ct20b wastegate on a ct26 turbo Housing(hybrid ct26/gt30) . So I'm curious if the actuator arm is hindering the flapper to fully close and open properly. In regards to porting the wastegate. Do I need to port both ports on wastegate ? And how much . I'm guessing use a drill bit? Quote Link to comment Share on other sites More sharing options...
koracing Posted May 25, 2023 Report Share Posted May 25, 2023 There should be no issue with that actuator on that turbo. They are physically inerchangeable. Porting is ususally done with a carbide rotary file or carbide burr on an air or electric die-grinder that accepts 1/4" shank bits. Follow this up with a barrel sanding cartridge roll on an arbor in the air tool or electric die grinder. You'll want to trace the outline of the flapper door when closed to ensure you're not porting out larger than the door will cover. You will need to open up both ports on the twin scroll housing. Usually I port out to within a couple mm of the flapper edge to get good controlled boost. (Note: More often I ditch the stock type turbos and go to an external wastegate with a larger aftermarket turbo) Quote Link to comment Share on other sites More sharing options...
exodus87 Posted May 25, 2023 Author Report Share Posted May 25, 2023 @koracing in regards to wastegate actuator arm it is actually longer than a ct20b arm . When swapping from ct26 actuator to ct20 it is needed to bend the arm out beciase it is too long for the door to close fully . I realized this last night when checking the arm connect to the flapper. With arm attached and pushed to limit out it is keeping the flapper door closed . There is not enough rod to open when pressure is applied. Long story short my flapper door has been such closed . Swapping new ct26 actuator tonight . Porting wise I might just have a shop do it Quote Link to comment Share on other sites More sharing options...
koracing Posted May 26, 2023 Report Share Posted May 26, 2023 It's been a while, but I recall them being the same dimensionally when I looked at them before, but it's been about 20 years since I was looking at both on a bench side by side. If it's stuck closed then that would certainly explain it. Quote Link to comment Share on other sites More sharing options...
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