Using a '93 3SGTE ECU on a '91 3SGTE Engine and Harness Options

[Dr_Tweak]

Some weeks back I had a customer doing a 3SGTE swap into a '91 Celica that I did a wiring conversion for. After he got it back and installed, I asked him for the part number on his ECU since I've seen many situations where the importers send the wrong ECU for the year of the harness. Sure enough, he had a '91 Harness but a '93 ECU. I advised him to get a '91 ECU, but he was having a hard time locating one.

About the same time, I started gathering parts and doing research for making jumper harnesses for various Toyota applications. I located the supplier for the female ECU plugs for a few different Toyota harnesses. When I got one in that matched the 3SGTE harnesses, I though, why not make a jumper harness that goes from a '91 harness to a '93 ECU, or a '93 harness to a '91 ECU? Then customers who run into this situation don't have to find another ECU or repin the whole harness.

Since I had this customer, Bryant, who had this very situation at hand, and since I happened to be going near where he lived on a recent road trip, I decided to whip up a prototype and give it a try.







There it is plugged into a 3SGE ECU as an example. This first one came out a little rough, the production model will be cleaner.

And here it is plugged into the car:



The jumper harness worked PERFECTLY. It fired up the first try and is running great, no codes and no problems at all

If anyone wants one of these jumper harnesses let me know, I'm currently building them to order.

Other applications for this setup include plug and play jumper harnesses for standalone units that don't already have a plug and play setup, like perhaps 3SGTE/Autronic, and so on.

-Doc

[Dr_Tweak]

No dude, I'm serious. I really want you to make one and put together a total cost. If you could consistently do it as the same quality using all brand-new parts, then I'll buy them from you. You think that you can consistently get brand-new parts for $50 each and it only takes two hours to make? And your time is obviously worth less than $75 an hour from your post, so what is your time worth? $10 an hour? $15? Seriously.

Considering that most shops charge an hourly rate of $60 - $80+ an hour, a shop is already overbudget if it takes you two hours and the parts cost you $50, not to mention that you would make zero profit because PROFIT what you SELL the item for minus the COST of the parts AND the COST OF MAKING IT.

Now sure, if you're big on doing it yourself, you could go find a Toyota ECU and hack the PCB connector off, find a harness and hack the plugs off, and then spend half a day trying to solder the wires to the right pins without melting the plastic housing and dislocating any of the pins, then yes, you could do the whole project for... pretty much nothing. People like that would never buy this product and wouldn't need help making one, so it's a moot point anyway.

What REALLY irritates me is that all day long I read people complaining that there aren't enough products for our cars out there and they wish someone would step up and make this or or that or this, and EVERY TIME I come out and actually produce a product or service and provide it to the community at a price that is reasonable while putting some food on my table, I get someone like you or Lagos saying, "Oh well, I guess Tweak is making a mint off of selling these/doing these swaps/wiring that engine...., you guys shouldn't buy this, or have him do your swap, you should just do the swap yourself or find some crappy used parts and solder them together and it'll be just as good..."

Here's a big to you!

-Doc

This post has been edited by Dr_Tweak: Jan 2, 2008 - 1:39 PM

[WannabeGT4]

No dude, I'm serious. I really want you to make one and put together a total cost. If you could consistently do it as the same quality using all brand-new parts, then I'll buy them from you. You think that you can consistently get brand-new parts for $50 each and it only takes two hours to make? And your time is obviously worth less than $75 an hour from your post, so what is your time worth? $10 an hour? $15? Seriously.

Considering that most shops charge an hourly rate of $60 - $80+ an hour, a shop is already overbudget if it takes you two hours and the parts cost you $50, not to mention that you would make zero profit because PROFIT what you SELL the item for minus the COST of the parts AND the COST OF MAKING IT.

Now sure, if you're big on doing it yourself, you could go find a Toyota ECU and hack the PCB connector off, find a harness and hack the plugs off, and then spend half a day trying to solder the wires to the right pins without melting the plastic housing and dislocating any of the pins, then yes, you could do the whole project for... pretty much nothing. People like that would never buy this product and wouldn't need help making one, so it's a moot point anyway.

What REALLY irritates me is that all day long I read people complaining that there aren't enough products for our cars out there and they wish someone would step up and make this or or that or this, and EVERY TIME I come out and actually produce a product or service and provide it to the community at a price that is reasonable while putting some food on my table, I get someone like you or Lagos saying, "Oh well, I guess Tweak is making a mint off of selling these/doing these swaps/wiring that engine...., you guys shouldn't buy this, or have him do your swap, you should just do the swap yourself or find some crappy used parts and solder them together and it'll be just as good..."

Here's a big to you!

-Doc

You ever stop and think that maybe it's your attitude that may be what's motivating us?

I said unless you think your time is worth more than $75 an hour this is quite profitable. If you're making these yourself there is no shop overhead to factor into the hourly rate. Just a flate rate of $75 per hour. It's just like you had a job doing work for $75 per hour.

If you disagree with the prices why don't you put up an itemized price list... Yeah, didn't think you were going to do that.

This post has been edited by WannabeGT4: Jan 3, 2008 - 7:39 AM

[BloodyStupidDave...]

If you disagree with the prices why don't you put up an itemized price list...

Okay, I'll bite.

Using a combination of your prices, RS, Vehicle Wiring Electronics and Trylon prices, each adapter requires:

$5.09 26 pin housing
$5.66 22 pin housing
$5.07 16 pin housing
$8.52 64 pin housing
$10.24 64 female pins
$10.24 64 male pins
$4.20 10m of 11amp thinwall cable (64 lengths of 15-16cm)
$2.48 2m of heatshrink (64 lengths of 3cm)
$2.00 24ml resin

Total parts, excluding sales tax, P&P: $53.50. I'm making assumptions on some quantities (such as guessing the amount of resin one would use); that housings and pins can be ordered individually (RS SSM is 50 for pins). Savings can be made for larger orders but it would seem unlikely that Dr. Tweak would shift more then 20 or so, so savings would be minimal.

I'd agree with both Dr. Tweak and Gary that assembly time is likely to be just under 2 hours. At the average of Dr. Tweaks' guideline quotes (which are comparable to similar shops in the UK), labour costs would be $140.

Whether Dr. Tweak uses a shop or not is irrelevant. A basic premise of business economics is that labour is never free even if you do the work yourself. If Dr. Tweak were to charge $30/hour for his time, add in £30/hour for premises, business rates, electricity/gas (power/heating/lighting) costs, insurance: Labour and overheads would still be $120. So the profit for the business would be a maximum of $25.50 on each item, or less than 15% profit (compared to the 25%-33% guideline for most businesses).

Or to look at it another way, for a healthy 30% profit, Dr. Tweak would need to be charging just $20/hour. I think that most people would agree his prices are appropriate, not extortionate.

Your only motivation here is to make money. You need to learn to coincide with the people here that are doing this as a hobby.

I think that is unfair. I don't believe that is his only motivation, although it is clearly a consideration as he is running a business afterall. I think your comment is quite revealing. You consider your Celica to be a hobby so you expect people to offer their services on a similar basis. It doesn't matter whether the organisation is the size of Toyota or the size of the some of the sole traders on here, that isn't going to happen. Toyota isn't going to offer to service your car at cost just because you are an enthusiast just as sole traders aren't going to run their businesses as charities. Sorry.

This post has been edited by BloodyStupidDavey: Jan 2, 2008 - 4:17 PM