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View Full Version : differance between a SC and non SC motor



boardfish
09-27-2011, 01:02 AM
looking to replace motor with JDM motor what is diff betweenSC and non SC?Can you just add the SC to nonSC JDM motor,thanks

terbennett
10-02-2011, 12:23 PM
They are two different engines internally. The N/A version is the 2TZ-FE and the S/C is the 2TZ-FZE. With the 2TZ-FZE the engine has stronger internals (pistons, sleeves, rods, etc.) with lower compression to handle the additional pressure of supercharging. In addition, the automatic transmission used in the 2TZ-FZE is a stronger transmission to handle the additional torque output of the S/C motor. Rear differential gear ratios are different too. The S/C has a more relaxed geared rear differential to help offset the lower fuel economy. Essentially, if you want it work right, you'll have to replace the engine, tranny and differential together. The replacing the ECU is another spot to be considered. Adding any type of forced induction to the N/A engine is costly due to the fact you will have to build the engine to handle the pressure of turbo- or supercharging. Then you have to consider the durability of your transmission since it wasn't designed for this application. Also the more aggressive rear diff will mean bad mpgs too.

Personally, I'd stick with the non S/C version. While it has less power, it seems to handle neglect better than the S/C model. IME, S/C models also have a greater chance for headgasket failure too. Most of the owners I've spoken to with the S/C models don't even know that you have to replace the fluid in the supercharger periodically. Not only that, you need two bottles of it and the fluid is around $45 per bottle. This is a Toyota dealer only item - which explains the high cost. Toyota also recommends premium fuel on the S/C eventhough I doubt that most owners actually use premium fuel. It runs okay without it but really, any forced induction car should be running on high octane premium fuel. It might cost a little more but your fuel economy will improve with premium on this van.

boardfish
10-09-2011, 08:37 PM
thanks for great amount of info. Now I know my head is cracked,is the SC head the same as the nonSC and interchangeale?Or does any places to get one,thanks

terbennett
10-09-2011, 09:19 PM
Not sure about the similarities between the two heads but it's safe to assume that they are different since the S/C has more done to it to lower the compression (and handle the supercharger) than just different bottom end internals. I had the headgasket done on one of my vans and due to it not being done correctly, it ended up going out a little over a year later. I would recommend a JDM engine swap. It was actually less money than if you are having a mechanic replace the head. Your best bet is to Google "low mileage Japanese engines in (your city or area)" or looking on EBay. Maybe your mechanic will be able to get one for you as well if you are using a mechanic. I've seen engines for as low as $400 on sale periodically and as high as $750. Labor is usually about $400-450 from what I was quoted when mine was swapped- which was just a few months ago.

boardfish
10-09-2011, 09:48 PM
Thanks for quick response.I think JDM is better investment,the motor I have has 240,000 allready and I am doing the work myself

terbennett
10-09-2011, 10:24 PM
I agree with you. Replacing the head on an old engine is just not a wise decision IMO. You will have a new head with 0 miles on a bottom end with 240,000 miles. You will at least have a 6 month warranty with the new motor and the turn around time to swap the engine is much faster than replacing head.

scottamann
10-10-2011, 05:00 AM
We did the Japanese motor thing 80,000 miles and 6 years ago. It's been great.

We decided to keep the motor the same as our version, so spent the money to keep all the American goo for emissions, etc. on it. Not sure I'd do that again, since it's never going to see a dealer, I suspect.