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Tremec TKX at the Track

66 Sat

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I've had the TKX in about 6 weeks now after replacing the 727. Yesterday evening was it's first outing at the track. After a 500 mile break-in I put the Tremec MTF fluid in and I was all set to go.

I've got the Mal Wood Underdash Hydraulic pedal unit so the only visible change under the hood is the small hydraulic reservoir mounted off the brake master cylinder bracket.

On the street it's great, has a nice positive shift and performs well. I was interested to see how it would go under high rpm, fast shifts with a helmet on and all the adrenaline of trying to beat my best (slow) quarter mile time.

Well it didn't disappoint. If it shifts well on the street then it shifts amazing on the track - I was worried about missing a shift but my concerns were unwarranted. It honestly feels laser-guided, going from 1st-2nd, 2nd-3rd, and then 3rd-4th, each shift just slams home without hesitation. These were at 5,000 rpm.
I don't need 5th gear at the track which is probably the slowest and trickiest shift on the street due to the distance from my body.

I did 7 passes, so 21 shifts at 5,000 rpm in total, all as positive as each other. This is on my opposite side too - for the the last 30 odd years I've been daily driving manuals and shifting with my left hand, but now I'm shifting with either hand, depending on what car I'm in.

It wasn't any quicker (or slower) than with the 727 which was a surprise as it feels much faster and more free revving. Overall I was very impressed.

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SCORE !
I wish that my Tremec TKO shifted as well as the new TKX models do. When I'm over 6200, it acts like there is a bar across the gate and the lever will not allow me to shift to 2nd. Once the rpms drop a bit, it slides right in. If I short shift at 5000, it is no problem.
How are you adjusting to having to declutch at stops and stop and go driving?
I love having a manual transmission but sometimes the clutch action in slow traffic is not much fun despite the hydraulic setup. That is the only time I miss the automatic.
 
Day to day driving is fine, but reverse parking is a bit more challenging than before, twisting around to look behind while juggling the clutch. I've had two close calls recently in carparks, pure fluke I didn't hit the concrete the last time.

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Remember you are adding an extra shift if you make it into fourth in the quarter. So unless you are Ronnie Sox there is an opportunity to slow down. Was the mph the same ?
 
Remember you are adding an extra shift if you make it into fourth in the quarter. So unless you are Ronnie Sox there is an opportunity to slow down. Was the mph the same ?
Best time - 14.558 @ 96.78 mph with the TKX & Edelbrock AVS2 650

Best time - 14.418 @ 98.54 mph with the 727 & Edelbrock AVS2 650

Best time - 14.104 @ 99.80 mph with the 727 & Holley 600 Vac Sec

I'm going again at the end of the month and I'm going to swap the Holley back on beforehand. Part of the problem is the shift into 4th is about 92 mph as power feels like it's trailing off with the AVS2 at 5,000 rpm. If the Holley will pull with power through to 5,500 rpm then I can leave it in 3rd.

I've got a whole spreadsheet on all my times and the differences between set-ups. It doesn't matter that I'm in the 14's, 13's, 12's whatever - the fun for me is trying to improve. That being said, I'm keen to finally get into the 13's and break 100 mph.
 
SCORE !
I wish that my Tremec TKO shifted as well as the new TKX models do. When I'm over 6200, it acts like there is a bar across the gate and the lever will not allow me to shift to 2nd. Once the rpms drop a bit, it slides right in. If I short shift at 5000, it is no problem.
How are you adjusting to having to declutch at stops and stop and go driving?
I love having a manual transmission but sometimes the clutch action in slow traffic is not much fun despite the hydraulic setup. That is the only time I miss the automatic.
Interesting... As you know, I just got my TKO together & I'm still learning it's quirks... But I've done a half dozen 1st-2nd shifts at 5700-6000 RPM's & it's been fine.. I haven't built the confidence to hit 3rd at that RPM yet but at 5100 which is about 60 mph it slides in great every time... Maybe the CF blocker rings I added do help....
 
Those are standard in the new TKX but we’re optional for the TKO. I didn’t think that I needed them.
The lady cam
I had wasn’t as strong at the high end. This cam just keeps going so shifting at 6000 feels like im
Short changing myself.
 
Nice! I was planning on switching to the TKX but have had no problems with my TKO. (Shifts nice at 7,750)
 
OP - what's your motor? I see the 354 Poly sticker on the air cleaner - that's the one?
I'm jealous that you were able to get 7 passes in. How far from home is your local track? Mine is 1.5 hrs + depending on traffic and the time I went there were so many cars I only got 3 passes in over a 3 hr period. I had better luck at a test and tune the day before a larger show up at Sac Raceway before they closed and got 6 runs in.
 
OP - what's your motor? I see the 354 Poly sticker on the air cleaner - that's the one?
I'm jealous that you were able to get 7 passes in. How far from home is your local track? Mine is 1.5 hrs + depending on traffic and the time I went there were so many cars I only got 3 passes in over a 3 hr period. I had better luck at a test and tune the day before a larger show up at Sac Raceway before they closed and got 6 runs in.
Yes engine is a 318 poly with a 3.58" crank. It should go faster, stock 4 barrel intake and a fairly small cam holds it back, but it's a great combo on the street. I'm going to port the intake on the advice of Gary Pavlovich which should help, and if cam changes weren't such a gamble these days I'd change that as well.
Local track is Willowbank Raceway. It's just over an hour away and is usually very busy on the Test and Tune nights but for whatever reason it was quiet with only about 30 cars. Also I got there before the gates opened for the time ever and was actually first lined up. It was spooky, I was the only car in the staging lanes, it was like my own private dragstrip.
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That isn't just opinion, that is reality for most of us.
 
I have a similar problem with my TKO (Kern Dog). It is not as smooth as I would like to do any spirited shifts. Any suggestions?
 
I have a similar problem with my TKO (Kern Dog). It is not as smooth as I would like to do any spirited shifts. Any suggestions?
I've done lots of reading but little real experience... Changing to different oils seems to help, I'm currently using Pennzoil Synchromesh... If your willing to go deeper Carbon Fiber Syncro blocker rings and brass shift finger pads are recommended... I have both, it still doesn't feel like an old musclecar box but it's not bad.. 2-3 & 3-2 you have to hit the gate right which is already becoming natural for me but if you hit it right it seems to go in gear pretty ease even at 6K... I'll probably work up to 6300 but my 340's power falls off soon after 6K so no reason to push it..
 
I've got the Mal Wood Underdash Hydraulic pedal unit so the only visible change under the hood is the small hydraulic reservoir mounted off the brake master cylinder bracket.

View attachment 1751451
Holy crap that pedal is awesome! Thanks for alerting me to it. Much cleaner solution than the kind that mount on the firewall.
 
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