orginal ecu with 20v?

kanga · 12-05-2007, 02:08 AM

well every where i read says you can't use the orignal 4a-ge ecu that came with the car with the 20v, but my dad says he used the original ecu in his NA mk1 when he swaped it in... is this true? and would this harm the engine at all?

mr220v · 12-05-2007, 10:21 AM

I have heard of people successfully running a 20v on 16v electronics of one sort or another. Two big issues:

1. 20v injectors are sized for sequential injection vs 16v batch injection which fire in pairs. You would need smaller sidefeed injectors otherwise you would run quite rich.

2. The only way to trigger vvt is with the tvis trigger. It's on and off at 4500rpms. The 20v vvt needs to be triggered at full throttle. It's more throttle based than rpm based.

These two issues assume that the 20v cam angle sensor can send an acceptable signal to the 16v ecu.

I have also heard of people getting the 20v running on the 4afe ecu.
you'd still have to do extensive modification to the 16v engine wiring harness to fit the 20v, so using a 16v ecu wouldn't save any wiring trouble.

From a cost standpoint, there is no good reason to use anything but a 20v ecu. You can purchase silvertop ecu's for around $100, and all the supporting electronics can be purchased for another $100 or so (coil, igniter, afm, o2). There would still be things to buy if you used a 16v or other toyota ecu.

Vyshino · 10-29-2009, 08:31 AM

Quote:

Originally Posted by mr220v

From a cost standpoint, there is no good reason to use anything but a 20v ecu. You can purchase silvertop ecu's for around $100, and all the supporting electronics can be purchased for another $100 or so (coil, igniter, afm, o2). There would still be things to buy if you used a 16v or other toyota ecu.

100$ eh? im having NO luck at all - i am bout ready to give up -
wondering bout the 16v blue top or red top ECUs to be used on the 20v.

if you have a 20v ST mt or a BT at/mt ECU id love to get my hands on one...

mr220v · 10-29-2009, 09:09 AM

Like I say, with a ton of changes, the 16v ecu could probably run the 20v. If not the old largeport ecu's, then the newer smallport ecu's.

It could physically run the motor, undoubtedly poorly though. 20v ecu's just aren't that expensive.

12-05-2007, 02:08 AM	#1 (permalink)
kanga ..brakes are over rated.. Join Date: Nov 2007 Location: from Nor Cal to Chandler, Az Posts: 168 Thanks: 17 Thanked 9 Times in 8 Posts iTrader Rating: (0/0% )	orginal ecu with 20v? well every where i read says you can't use the orignal 4a-ge ecu that came with the car with the 20v, but my dad says he used the original ecu in his NA mk1 when he swaped it in... is this true? and would this harm the engine at all?

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12-05-2007, 10:21 AM	#2 (permalink)
mr220v Beams Owners Group Join Date: Mar 2006 Posts: 1,791 Thanks: 13 Thanked 139 Times in 117 Posts iTrader Rating: (9/100% )	I have heard of people successfully running a 20v on 16v electronics of one sort or another. Two big issues: 1. 20v injectors are sized for sequential injection vs 16v batch injection which fire in pairs. You would need smaller sidefeed injectors otherwise you would run quite rich. 2. The only way to trigger vvt is with the tvis trigger. It's on and off at 4500rpms. The 20v vvt needs to be triggered at full throttle. It's more throttle based than rpm based. These two issues assume that the 20v cam angle sensor can send an acceptable signal to the 16v ecu. I have also heard of people getting the 20v running on the 4afe ecu. you'd still have to do extensive modification to the 16v engine wiring harness to fit the 20v, so using a 16v ecu wouldn't save any wiring trouble. From a cost standpoint, there is no good reason to use anything but a 20v ecu. You can purchase silvertop ecu's for around $100, and all the supporting electronics can be purchased for another $100 or so (coil, igniter, afm, o2). There would still be things to buy if you used a 16v or other toyota ecu.

10-29-2009, 09:09 AM	#4 (permalink)
mr220v Beams Owners Group Join Date: Mar 2006 Posts: 1,791 Thanks: 13 Thanked 139 Times in 117 Posts iTrader Rating: (9/100% )	Like I say, with a ton of changes, the 16v ecu could probably run the 20v. If not the old largeport ecu's, then the newer smallport ecu's. It could physically run the motor, undoubtedly poorly though. 20v ecu's just aren't that expensive.