secret squirrel Posted April 13, 2009 Share Posted April 13, 2009 Hi guys, I'm from the land of Oz and I'm probably going to drop a 5efe into my starlet because I can do it for practically nothing other than time. I plan on leaving the 4efe ECU in place and transfering the TPS and W/T sensors because it gets a bit hot in queensland and A/C is a necessity which seems to be the only area that the 5efe and the 4efe looms seem to differ.So, my question is : Has anyone ever actually had there car checked on a dyno or via a wideband to see what the AFR's are like running the 5efe motor on the 4efe ECU?To my thinking, closed loop should behave exactly the same and as both engines are physically identical (most importantly the head and therefore flow capabilities) except for stroke (capacity), then it should be fine. It will just run 1-2 load reference pionts higher accross the map due to the extra load (amount of air being injested) from the larger capacity. In turn, compensating with more fuel.Hopefully someone was thourough enough to have there car tested?Any first hand, accurate information would be most appreciated. P.S. I'm a mechanic that has dabbled in tuning before so feel free to get as in depth as you find necessary Quote Link to post Share on other sites
ste91 Posted April 13, 2009 Share Posted April 13, 2009 AFAIK the 4EFE ECU runs fine on the 5EFE and I think a fair few people have done it. Quote Link to post Share on other sites
Jozinobi Posted April 13, 2009 Share Posted April 13, 2009 Surprising as it may be I don't think anyone that I know of has tested their 5EFE converted EP91 for AFR on the 4EFE ecu.Yes I may be running more volume and air capacity with my engine but the general state of tune is still the same.I was at my tuners last week and we took the starlet for a run with the 4EFE ecu. I cant give you the exact air/fuel ratio however it started to get very lean from mid range to top end revs. We used wideband with AFR display and emanage ultimate.What Im trying to say is yes the 4EFE ecu will run the 5EFE but it is far from ideal, although both engines are 98% similar they do have different compression ratios and other small details which would make them run different apart from the obvious displacement increase. Don't assume that everything will be just fine because it is obvious that the 4EFE ecu wont fuel the 5EFE 'perfectly'. Instead of compensating with more fuel, its seems to retard the fuel to be on the safe side, this is exactly what is happening with mine. I'm no engine mapper/tuner but I can tell you it certainly wasnt running to its full potential.I understand you are trying to get concrete answers but to be honest I would not make such hard work about it. It is basically a plug and play engine. Seeing as you have easy access to this engine you have nothing to lose from trying it out. What car is it from exactly because over here we work with UK 5EFE from Toyota Paseos, so the one you have there may be a variation which is something we have no experience in besides the import 5EFHEs from Cynos and Sera.As for your queries about retaining A/C (via pm), its something that we cannot help you with as our UK ep91 do not come with it as standard. We just got the hot and cold heater. However Im sure someone with more logic can explain that one. Tuning is all about discovering for yourself what can be done, there are usually so many different variables as you have read that there is no right answer for it. Don't expect a world of difference but the conversion will make the EP into a more drivable car for everyday situations.Apologies if I could not be more exact with answering your specific questions however all I did was buy a full UK 5EFE, booked it into my mechanic to fit, and voila, everything was plug and play besides one or two sensors and retaining the 4EFE throttlebody it worked a treat. All other fine tuning is up to you.I sincerely hope that you can get this sorted as it would be waste not to try that engine out. Any of those other queries you sent me feel free to post them up, as there are others who may be able to give you some advice, especially on the air con being retained with the use of a different ecu etc. You seem to have the resources available to complete this conversion so I would definately look into it.RegardsJoz Quote Link to post Share on other sites
secret squirrel Posted April 13, 2009 Author Share Posted April 13, 2009 We have every version of the 5efe over here with every version of paseo included the (also rare here) 5efhe. I've got access to a (what should be a straight swap) dumb as dog dodo early version 5efe from a paseo which I intend on horing for it's seats, P/S and rear disc brakes also. I will write a more detailed reply but It is time to go to work fo me . Joz, did you go for a run with your tuner with your 5efe or your now 5efhe? As I said in the PM, that would make a huge difference.Thankyou for your replies and keep them coming if anyone has something to add .I'll drop in after work. . . . Matt Quote Link to post Share on other sites
Jozinobi Posted April 13, 2009 Share Posted April 13, 2009 I went for the tune up with the 5EFHE engine Matt.I understand there would be some difference but I believe its the closest anyone has got to discovering the afr ratios for that particular combination (4efe ecu and 5e engine) in the UK.Looking forward to your reply mate.Joz Quote Link to post Share on other sites
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