TRD/ Magnuson 4.0 Supercharger Tips, Tricks, and Mods

If you have 2.8 pulley or stock I would stick with the stock 70.5" length. Gates makes a racing belt in that size.

 

I understand your frustration but it is a known fact from people here that have had the TRD tune and Bully Pig tune that the UCON works better with an unflashed ecu.

Scott (the designer and programmer of the UCON) has said it's difficult to tune the UCON to a flashed ecu. Maybe he has refined the tune since it's been more than 6 months that he said that.

He can remote in to reflash the UCON if you decide to get a stock ecu.

 

And I just found my old continental belt box with it in it as my spare. Yep 70.5 and the boxes of NGK plugs boxes. Yeah they are not the ones I thought. They are some 6 heat range ones. That is hotter right? I need to get those out of there! Now to order 22's or 24's?

 

Also I thought they only had issues with like 2011 and up trd tunes?

 

NGK 10 9 8 7 6 5
DENSO 31 27 24 22 20 16

https://www.briskracing.com/heat-range-cross-reference-table

 

Not sure on that one.

 

That is what I was thinking! I went hotter! Man I hope those were random boxes and that isn't what I put in. But I am taking whatever out and going with Denso 22 or 24. Probably 22 since I can get them from Toyota overnight.

 

It was the 2012’s and up.

09-11 (that I know of) was what the ucon was partially designed with (I heard that from somewhere on TW). I can also vouch that my ‘11 had no issues upon initial start up and riding around town. It was not until I hit hwy speeds (65-75 mph) that I started tripping “pending CELs” from my UCON, which Scott and I got worked out quickly.

 

Dont sell her. With all the info here there is definitely a solution in sight.

 

Just pull one of the passenger side ones real quick to check.

 

@mr.trd You have a 2.8 pulley, that is a great starting point right there. If you have an intake on the supercharger or plan to run one or you are hitting more than 7.5lbs of boost on your boost gauge run the

$9 IKH22 Iridium Power Spark Plug, (Pack of 1)

IKH22's. Glass smooth idle.

 

He said he is only at 3 to 3.5 psi at 4000ft elevation. Stock supercharger plugs are 22's. If you ever plan for any other power boosters go for the 24's.

 

The 24s are one step colder correct? From my reading ive heard that colder plugs help prevent spark knock

 

20's are stock
22's are stock supercharger
24's are one step closer than stick supercharger

They can help. They dissipate heat faster than a hotter plug.

 

Oh yeah, oops. I meant 24's.

At boost that low I would stick to 22's then.

 

He is trying to fix his boost problem, that's how this all started.

 

It has to be something with the bypass valve. Maybe not sealing correctly or something. If there was a leak somewhere you would get a code. Or maybe the blower has something wrong with it.

 

Just reading up on elevation and boost found this



At 4000 ft above sea level we need to figure out what 40.8% greater than ambient is. 12.7 X1.408 = 17.88 psi absolute. That’s a loss of 13.624% pressure from sea level. This is what a mechanically driven supercharger will yield if it is designed to provide 40.8% more air (6 psi at sea level). Your mechanically driven supercharger’s boost gauge now reads 3.18 psi while the turbo’s will still read 6 psi. A turbo has the advantage by 2.82 psi. A naturally aspirated engine loses 13.606% pressure at this same elevation over sea level. An exhaust driven turbocharged engine will get a total of 20.7 psi absolute or a 0% pressure loss
since the wastegate is calibrated to sea level or a fixed spring pressure.


So if it’s supose to be at 6 psi. Which is around normal for 2.8. 6-7 psi. And ur reading around 3 seems right. Might be ur problem right there. Just elevation. Put a 2.5 on that thing and boost on

 

I agree with this! @12TRDTacoma had said he had issues with his bypass valve vacuum line not sealing. That would cause the valve to not close. That is one of the reasons I wanted him to get video or have someone romp on it parked so he could get a visual if it was actuating. Even then if the line is leaking it will lose vacuum and possibly not close the bypass valve all the way.

I have also adjusted my bypass valve before I ever installed the ac. I DONT recommend this to all but I definitely got mine to close further before the butterfly would stick then they had set from factory. I'm sure they add in a safety margin for wear, etc.

All of this would make perfect sense because he has the TRD tune, is super rich, even with smaller pulley. Yes elevation is a factor but he also probably has corresponding cooler temps to go with it.

 

Yep the more I read about elevation and boost the more I am hesitant that I really have a boost issue. Just a super rich issue. Last week while I was in MT I was hitting 5. But never had any long drives so I just figured maybe the belt held better until everything got heat soaked and that it was slipping. MT has high elevation too, right. Not really. My parents place up against the mountain in Thompson Falls is at 2400 ft. Low enough to hit 5 lbs I guess. But the ucon and a Dayco 5050705 and a set of NGK LFR7AIX's are going in on Monday. I did look up my old PO on the current spark bolts and they are wrong. Not sure the actual performance problem they may be causing, but they are BKR7EIX they have a 1/4" less reach. Thank you all for your help!