EA81 supercharger revamp by Tweety

tambox · Post by **tambox** » Mon Sep 09, 2013 8:38 pm

They may be the same, electronically, just one is the later version that was made to overcome the faults in the initial one.
Maybe.
Sun is still ok, just packing some toys to bring.

Tweety · Post by **Tweety** » Mon Sep 09, 2013 9:21 pm

yes tambox, agree with that. There is actually at least 3 versions. my error is not ordering one with the housing/alloy unit. I am finding many on the net now and will order another with the housing.

Sun is still on.

Tweety · Post by **Tweety** » Mon Sep 09, 2013 10:59 pm

I'll wait till after Sunday Greg before I seek another unit. we can test this unit first. have asked forumites on USMB if they can supply a junkyard that has some MAF assemblies.

Post by **Bantum** » Mon Sep 09, 2013 11:12 pm

Query : Have you tried FROG for the part ?

Cheers, Bantum ...

Tweety · Post by **Tweety** » Tue Sep 10, 2013 6:13 pm

Yeh Greg, no chance there. and the part - the sensor will need the housing with it. Will see how we go on the weekend. We can test the original one, even grind down the purchased one, ride the trike without one connected etc to see how we go.

Recoed one that have allegedly been tested range from $125-220 US plus postage.

http://www.partsmonkey.com/en/catalogue ... low-sensor this one for $247US

steptoe · Post by **steptoe** » Tue Sep 10, 2013 7:17 pm

starting to think my PM didn't get tru to you Tony, labelled it SEX! to get your attention - maybe it got zapped !

rockauto have them @ 165 new? and reco ....

Tweety · Post by **Tweety** » Tue Sep 10, 2013 9:01 pm

Jonno, I thought it was spam lol....

Just looked it all up. this one is listed as being 1986-1987, the year my system was made. Just ordered one. The more expensive alloy housing type. plus a coolant temperature sender which can effect the performance in a similar manner- its only $5 AUS extra. Gee Rockauto have a lot of stuff.

Tweety · Post by **Tweety** » Tue Sep 10, 2013 9:04 pm

The item purchased

steptoe · Post by **steptoe** » Wed Sep 11, 2013 7:45 am

Wouldn't you think they'd send me a Rockauto.com T-shirt for that

Surprised you just went in there , ordered and back again, I almost need meals delivered when I go to visit !

Tweety · Post by **Tweety** » Wed Sep 11, 2013 8:19 am

haha. well considering I'd covered every other site, seen some crappy examples of MAF assemblies for sale for as little as $25 but thinking of the expense of the postage wanted a better unit. Then go into http://www.rockauto.com and they ahve 3 units and they list the year that they are compatible with- it was a no brainer. top site that.

YouTube · Post by **El_Freddo** » Fri Sep 13, 2013 7:52 pm

I hope this solves the issue mate, you're so close!

Chers

Bennie

Tweety · Post by **Tweety** » Fri Sep 13, 2013 9:04 pm

yeh Scott, I do think I am close to curtain close. It might be down on power but already the difference in smooth running, cleaner engine and easy starting are impressive. No regrets.

With the new sump gasket there seems no oil loss on the dip stick. Might get a few years out of this engine and postpone the new one planned for 2014. Even considering just getting a set of heads recoed with a shave for the higher CR.

This means a fast track to stage 3- engineers report including approaval for a higher towing capacity, cosmetic spruce up. New screen and another sunroof.

Things are looking up!.

Tweety · Post by **Tweety** » Sun Sep 15, 2013 4:22 pm

Today a big thankyou to Greg (tambox) for attending my place today. A long ride for you mate.

I'll leave the technical details to Greg to explain. But the trike runs out great in first and second on the 3 speed auto. It when it gets into 3rd it goes max 105kph and had a huge dead spot - (worse that a flat spot)

Sitting in the rear seat Greg mad two multi meters. The MAF went to a max of 3.4volts. We believe it should go to 5 volts. I have two being shipped here from the states.

Seeking specs from USMB as we speak on all sensors. Internal engine wear like wear on cam lobes could be an issue.

Tony

tambox · Post by **tambox** » Sun Sep 15, 2013 6:29 pm

It was a nice ride, thank you Tony for putting on the great weather.

Tweety is lacking grunt, sort of like when you go up a hill in top gear, you reach a point where no matter how much further you press the accelerator, it makes no difference.
Why??
Some readings.
At idle the MAF is at about 0.7v, duty cycle 6%.
When accelerating hard through 1st/2nd, till the auto upshifts @4500rpm (guessed), the MAF slowly climbs to 3.4v and the duty cycle slowly climbs to 46%. The rate of increase is in sync with the RPM increase.

In top gear, past the kickdown point, at full throttle the MAF is 2.7v and the duty cycle is 36%, thats where they stay, on a constant incline. As the accelerator is released, the MAF and duty stay very close to 2.7/36, until the butterfly starts to reduce the required air and Tweety slows, the MAF/duty drop in sync with the rpm. The motor has no signs of pinging, when like this.

Disconnecting the MAF, increases the duty cycle by about 2%, through the whole rev range, Tweety still runs fine without it, just a bit richer. This had no effect on full throttle performance in top gear.

The temp sensor measured approx where it should be.

From the limited information available, it seems the MAF voltage is lower than what it should be.

Is it the MAF, or is it the motor is worn and cannot get the higher air flow ??

Tony equiped with a duty cycle meter and a new MAF will answer some more questions, soon.

Subydoug · Post by **Subydoug** » Sun Sep 15, 2013 6:49 pm

Hmm, did you guys check the signal coming from the TPS? May be worth a probe while someone actuates the throttle, just to make sure its giving a full swing. Those MAF readings sound pretty good to me. I would have thought that the duty cycle would be higher then that at WOT.....

Regards

Doug

tambox · Post by **tambox** » Sun Sep 15, 2013 7:19 pm

I think its only got an idle switch TPS, as the workshop manual settings are O/C only at just off idle.
As tony said, he had it serviced by an EFI specialist, who did a lot of checks/settings/cleaning.
TPS Should not worry anything after that, as it revs out in the lower gears, it seems the TPS is ok.
As it has the idle switch type TPS the duty cycle is based on the MAF, not the throttle.
Varying the throttle, above cruise, has no effect on the duty cycle, but as the MAF increases, so does the duty cycle.
Early model ECU system, very basic, give it what it needs, not what it wants.

From the readings, they show the duty cycle is in snyc with the air flow, at cruise the MAF sits about 1.8-2.2V, duty around 20-26%.
Just at WOT in top, it stops at a terminal velocity point.

Subydoug · Post by **Subydoug** » Sun Sep 15, 2013 7:50 pm

Oh really? Pretty sure the TPS on my mpfi stuff also has a part throttle and WOT signal. Seems odd that subaru would use a different setup. I suppose the first sign of TPS issues would be a stumble on takeoff.

Sounds simple but there isnt a hole not blocked off somewhere on the intake ducting thats letting air bypass the MAF is there? All the emissions hoses correct?

Well tweety, if the new MAF sensor doesnt work Il make you a little box to put between the MAF and ECU which will let you increase or decrease that signal at will.

Regards

Doug

tambox · Post by **tambox** » Sun Sep 15, 2013 8:00 pm

After internetting some info, it may have a WOT set of contacts, not mentioned in the setup instructions.
According to USMB, the WOT contacts connect at 45 deg past the idle contacts.
Once Tony buys a working:rolleyes: multimeter he can check it.
If that is not working it will make a difference.

steptoe · Post by **steptoe** » Sun Sep 15, 2013 8:54 pm

Seems odd....my rrrr's

There are so many thigs different between MY and L's that could have remained the same - such as the direction the door key needs to lock or unlock, the radiator support pins ...and not to mentin why Fuji went spfi in its later years in L's in the US ! 1300cc in L Series.

After stuffing around with my power supplies an idea popped into my head for Tweety. Tony, what about using a USB adaptor plug in your 12V socket to get 5V output to feed to that wire Greg was playing with, say on a switch that you or someone as brave as Debbie or Greg could flick at the Delorean speed of 105kph see if it gives it a burst !! ??

Subydoug · Post by **Subydoug** » Sun Sep 15, 2013 9:12 pm

Could be dangerous doing that steptoe. The charger is capable of delivering a fair amount of current and unless the ECU has a high inpedance input it could damage the ecu. Doesnt mean you cant do it, but it you do, run it thru something like a 10k resistor so it cant flow any current.

Regards

Doug