EVO 8/9 Synchrotech Carbon Synchros
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.
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.
i wonder if carbon synchros help the trans run cooler as well.
Okay so I've had my carbon synchros for about a year now with roughly 1200 miles of general cruising and some spirited drives with no issues to note. I would agree in saying they aren't a miracle mod by any means, but coupled with a twin disc they shift very well at higher RPM's. Shifts are a tad notchy while the trans warms up, nothing crazy, but worth mentioning. Once warmed up, the trans feels great. Obviously coming from a trans with some miles it feels much tighter after a rebuild with these units, and as others have said before me, I as well will be buying these again upon my next reuild. I plan to hit the track this year once I complete my winter projects, and will try to update after doing so.
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Okay so I've had my carbon synchros for about a year now with roughly 1200 miles of general cruising and some spirited drives with no issues to note. I would agree in saying they aren't a miracle mod by any means, but coupled with a twin disc they shift very well at higher RPM's. Shifts are a tad notchy while the trans warms up, nothing crazy, but worth mentioning. Once warmed up, the trans feels great. Obviously coming from a trans with some miles it feels much tighter after a rebuild with these units, and as others have said before me, I as well will be buying these again upon my next reuild. I plan to hit the track this year once I complete my winter projects, and will try to update after doing so.
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From: San Dimas
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From: Ashdod
Originally Posted by kyoo
what'd the first flush look like?
Joined: Dec 2010
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From: Winchestertonfieldville (Rochester, NY)
First flush was not black, actually wasn't really terribly dirty at all and that was at 50 miles. 2nd one at 500 was slight gray tinge but nothing crazy.
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From: Dubai
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From: South Africa
digging up an old post.
Any long term reviews on these ? What lifespan are you guys getting , 10-15k miles ?
use my car on weekends only, and some strip time. Dont do more than 4k miles a year.
Any long term reviews on these ? What lifespan are you guys getting , 10-15k miles ?
use my car on weekends only, and some strip time. Dont do more than 4k miles a year.
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From: Uae
just go to a good gear guy to have em installed.
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From: Winchestertonfieldville (Rochester, NY)
I have ran SyncroTech Carbon synchros for the last 6 years with ZERO issues. I've even left some pretty detailed reviews in this thread to help others. I installed brand new 2/3/4 synchros and springs with new 3/4 slider a few weeks back and finally got the car together last week. Mainly did it out of routine maintenance because of the cars power/usage but with the around 10k miles of use it wasn't completely necessary.
25 miles into my break in driving, 3rd clunks into gear, hard. Which to me meant the synchro wasn't slowing the gear to match with itself. Tore it down last night and sure enough, the Carbon literally disintegrated off the synchro and was just free spinning on the gear. I used RedLine MT85, warmed car up for 10 minutes before even moving the shifter and never went above 3k RPM because I know how important a gentle, shift heavy break in is for these kind of parts. Synchros were also coated in oil before installation so they were never dry. Here's a picture of the 4th synchro which looks brand new (because it is). Didn't check 2nd yet but I can say, I am super disappointed. I missed a Dyno Appt at STM, and also the first No Prep race of the year, $100 in drivetrain fluids etc etc. I sent an email in last week when I had the issue and the rep @Synchrotech has been easy to deal with thus far, he was just waiting on disassembly to verify the issue.
I will also say, when that Carbon comes apart it gets EVERYWHERE. My brand new trans fluid looks like 10k mile conventional motor oil. I am going to have to completely disassemble and throughly clean everything, again which is also upsetting. I sent pics in with some detail around the issue last night and I don't suspect they'll give me a hard time. I'd like to think this is just one of those times where this can happen randomly but I am seriously reconsidering using OEM synchros after this, even after years of success this was enough to change my perception.
