VAGRANT Posted July 28, 2010 Share Posted July 28, 2010 I have a 2t-geu with efi stripped off. Running 2 40mm dcoe webers, Electronic ignition and worked cams, ported and polished head. has a facet fuel pump and have had the carbs dyno tuned. Haven't got adjustable cam gears. engine work was done about 7 years ago and the project has never been fully finished. partially due to lost interest due to running issue! Have recently renewed my enthusiasim but need to fix 'Gurggle'. When i use even just partial throttle below 3000 rpm the engine just gurgles. once over 3000 ish rpm theres no problem! it revs out faster than i can change gears. but thats not what i want!!!! thinking maybe its cam timing issue and i need to spend money on adjustable cam gears but over and above that... ive lost original paper work for the cam grind etc... Any thoughts? Quote Link to comment Share on other sites More sharing options...
R100 Posted July 28, 2010 Share Posted July 28, 2010 My old Toyota Levin did the same thing. Everything was factory on it including the 2TG except i had twin solex's from memory. Nothing i could do to the tune would make it run any better. Under 3000rpm it just made massive induction gurgling noises and had the power of a toyota 3K but after 3000 it really opened up. Yours could possibly be an ignition timing issue ? Quote Link to comment Share on other sites More sharing options...
Unclejake Posted July 28, 2010 Share Posted July 28, 2010 1) What is a 2T-Geu......... and assuming your advance curve is correct and your base timing settings are correct: 2) What venturis and main jets are you using 3) Have you adjusted the carb idle mixture via the four screws (with the springs underneath them) closest to the manifold 4) Are the carbs balanced Quote Link to comment Share on other sites More sharing options...
VAGRANT Posted July 28, 2010 Author Share Posted July 28, 2010 2t-geu was a later version of the celica 2t-b engine. original was a push rod 1600 2t-geu is the same block but with yamaha dohc head on it and efi. Carbs were balanced adjusted and tuned on a dyno by a local tuning company.. Quote Link to comment Share on other sites More sharing options...
Unclejake Posted July 28, 2010 Share Posted July 28, 2010 So roughly 400cc per carb throat then? Too rich in the main jet or too big in the venturi (air speed too low) would do this but I am tending toward bad idle mixture adjustment or a vacuum leak Quote Link to comment Share on other sites More sharing options...
VAGRANT Posted July 28, 2010 Author Share Posted July 28, 2010 Its been a while but i think i have 30 or 32 mm venturi's had thought about possible over porting and was going to try ram tubes to speed up the air intake. Not much room between carb mouth and right strut tower. i imagine if i were to adjust idle mixture screws by small incrimints at a time then i should be able to make adjustments reasonable evenly......?? Quote Link to comment Share on other sites More sharing options...
Unclejake Posted July 28, 2010 Share Posted July 28, 2010 30-32mm venturis sounds perfectly reasonable. To achieve anything with the idle mixture you need to be certain the timing is steady and around about right first, but the adjustment of the idle mixture is not something you can just prod at a wee bit. You need to go in there boots and all. It is very, very easy to do and is well documented online. I am basing all the above on you having the symptom of a bad progression from light throttle to medium/open throttle. If I have not understood your symptom properly then ignore me. 1) Check the timing is steady at idle and advances after 1,200RPM. All advance should be in by 3,000RPM? 2) Check you have no vacuum leaks 3) Check your venturis and jets are about right against a reliable reference source (remembering that all motors are different). A HUGE pump jet could do this but they don't really get that big. There is a pump jet buried at the bottom of the float bowl that I don't know much about. 4) Adjust idle mixture. You can't do much harm if you look it up first Quote Link to comment Share on other sites More sharing options...
VAGRANT Posted July 28, 2010 Author Share Posted July 28, 2010 no computer at all.. has hall effect (or similar) triggering a module that triggers coil. dyno sheet in km/h not rpm but is very jumpy looking below 80km ..... could be gear changes...unsure. Quote Link to comment Share on other sites More sharing options...
KKtrips Posted July 28, 2010 Share Posted July 28, 2010 did/does the efi computer control the ignition timing? Did the dyno sheets show lack of power below 3000rpm? Quote Link to comment Share on other sites More sharing options...
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