Also curious....I bought these on the group buy a long time ago because I'd be rebuilding my transmission at some point.

Would love to hear what others have to say as well...don't want to get something installed that I have to go back and fix a year later

From what we'd heard from the honda people (which synchrotech has been around a long time) they all loved them

 

what is the redline cocktail? you're not running any shockproof in there are you?

 

Cocktail for CT9A's is 2 qts of MT90 and 1qt of MTL.

 

why not just run mt85

 

MT85 didn't exist back then when someone thought up the idea of making that cocktail :P

 

shockproof only in the tcase boss!

 

will do. BTW what clutch r u on?

 

Carbonetic Full Blade. Awesome clutch if not abused. Easier than stock to modulate but holds 450 ft-lbs.

 

I followed this thread before I pulled the trigger on the Syncrotech Carbon's. There really isn't any conclusive reporting in the 30 pages so far. Everyone just adds to the questions, so I'll do my best to make it plain. I have the carbon syncros. I am somewhat of a driver. My VIII in its current form is sitting in the 530ish whp area on STM's Mustang dyno for reference (750hp VD), the car on kill mode has trapped in the 140's going low 10's on a beat drivetrain making 650hp on the same dyno/setup.

When driving around town, compared to a 60k mile old trans that was beat to death, the carbon syncro's feel smoother, or engage nicer, than the previous used unit. Downshifts happen much easier, there is less direct effort needed on the shifter to engage the gear. Upshifting at high RPM's feels like it should. That's a little vague, but any time you bang a gear and it goes right in, that's kosher to me. I have shifted in the 8500-9k rev range and not had any issues. They are not magical in nature by any means, but I am satisfied with them.

I have had TRE do a few trans builds for me in my DSM days, and as far as quality of the shift I would say it is similar to that of a properly built OEM syncro transmission. Syncrotech has improved the tooth profile to aid in engagement of the syncro, so that has to count for something. These are still an oem style syncro, with carbon deposits where the syncro rides on the shaft to reduce friction. I noticed the trans needs to be warmed up to experience the best shift quality, and by warmed up I mean at least 5-10 miles of driving. It is notchy when cold, like most of our cars.


10.29@141 on a stock transmission with QM 8 leg with a 4.70 330' (for those that are 1/4 time savy). This trans almost never went into gear easily under 7k, causing a lot of transient response issues even with me forcing it, especially from 1-2 at high RPM's.

10.40@133 with a 4.30 330' with the carbon syncro build. Both 60' times were high 1.6's.

The main thing for me is how long will this last? So far I have alittle over 1k miles on the setup and 5 track passes at 530whp. They're supposed to outperform OEM syncros in every way and as far as that goes only time will tell.

If I did it over again, I would get them again for what it's worth.

 

that's all good to hear!

granted you're only one person, but still good to hear haha

 

I'm currently getting some Carbon synchros in my trans thats being built at RRT Motorsports. I will also add some input once I get some time driving with them

 

Put a few hard track miles on the car.

So far, on redline cocktail mix, I'm impressed with the synchros. Shifts far better than the old transmission ever did. Had an Exedy twin carbon in the car back then, and it shifts better with an ACT clutch now, will update again after the RPS Carbon clutch is installed.

First fluid change looked relatively clean, no metal chunks but it has a glimmer of fine metal in the oil (Normal after a rebuild). Changing to Motul for the next race in a week's time. I'll have another update out shortly.

I usually end up killing a transmission every season, if this survives longer than a season I'll be *impressed*. It's a time attack car running big slicks and aero.

Closing thoughts
Would recommend, friend says it shifts better than a TRE OE synchro box, and before that he was in love with his transmission... until he drove mine lol

 

How are you killing it? Lock out, shred a gear?

 

Bent and discolored shift forks

impacted gears (not sheered, but not usable either)

discolored/bent synchros

bent shift keys


Most of my issues stem from getting the trans too hot.

 

Hi Everyone,

We have had quite a few inquiries about making the EVO 8/9 MR 6 speed synchros. I will be starting a new interest thread for them and look forward to your input.

Thanks - David