3.391
2.319
1.725
1.295
1.000
Life beyond synchros...
Regardless of torque capacity, does one really want to limit their shift speed?
The bigger the turbo, the more important this topic becomes.
You should buy a samsonas.
You should have placed the order 9-12 months ago.
In that price range, I might look at the Tremec T56 Magnum. I like the top loader shifter since it won’t lose the geometry due to flex of motor and trans mounts under load/windup.
For drag specific use the Ford C4 or the Chevy 3 speed others are working on adapting.
I would guess the drag racing season is shorter on PEI than in NH. If you have to do all the safety stuff we have to do here, the car you don’t drive very much now will become a car you barely ever drive.
Why not go with a s6-53?
Sent from my iPhone using Tapatalk
1989 535i - sold
1999 M3 Tiag/Dove - sold
1998 M3 Turbo Arctic/black - current
2004 Built motor TiAg/Black - Sold
2008 E61 19T Turbo-Wagon - current
2011 E82 135i - S85 Swap - current
1998 M3 Cosmos S54 swapped Sedan - current
1998 Turbo: PTE6870 | 1.15 ar | Hp Cover, Custom Divided T4 bottom-mount, 3.5" SS exhaust, Dual Turbosmart Compgates, Turbosmart Raceport BOV, 3.5" Treadstone Intercooler, 3.5" Vibrant resonator and muffler, Arp 2k Headstuds | Arp 2k Main studs | 87mm Je pistons | Eagle rods | 9.2:1 static compression, Ces 87mm cutring, Custom solid rear subframe bushings, Akg 85d diff bushings, 4 clutch 3.15 diff, , Poly engine mounts, UUC trans mounts W/ enforcers, 22RPD OBD2 Stock ECU id1700 E85 tune, 22RPD Big power Transmission swap w/ GS6-53
Thanks to a gluttonous global economy over many decades, and a complete disregard for environmental consequences, PEI might have it's summer drag racing season expanded from 4 to 6 months! Woo hoo!
The TH400 is still under consideration, but I am more focused on how fun the car is to drive, vs how outright quick it is. I still want to take it on road courses, and then there's my unfulfilled ambition from the black car of doing Targa NFLD.
Shift speed.
I'm looking to go to a dog box, with non-H pattern shifting.
After a few revisions, this is the gearing that I'll be using:
3.391
2.186
1.670
1.295
1.000
Diff is 3.62
You take this thing on the highway at all? 1:1 with a 3.62 would get... old.
Don't you need dog style engadgement for high power stuff? Pretty sure synchro transmissions are just prone to not shifting under high power reguardless of who it's by. I'm sure that's an arm and a leg option for BMW.
Where I live, I would have a really hard time seeing that speed on public roads.
The gearing is for the drag strip.
If I wanted to do something else, like an airstrip event, I would just change the diff.
I bought a GForce GF-5R:
Dog engagement
Straight cut gears
Guess I'm lazy as I'm sure you've covered it but any reason why you are wanting manuel transmission? I know they do keep certain classes in drag racing.
Enjoy the straight gears, rally car noises incoming.
Synchros are for synchronizing the internal shafts of the transmission, they are not meant to be exposed to any load beyond the momentum of the shafts and gears. So the amount of power the transmission is fed by the motor is irrelevant but what does matter is the violence of the shifts. If you try to shift a synchronized transmission quickly, even though the mass of the transmission shafts isn't very significant, asking the change in velocity to happen very quickly results in a LOT of force which the synchronizer clutches aren't meant for and will wear out prematurely. This is when the transmission will appear to be hard shifting.
That's where the dog boxes shine because while they are painful to drive casually/inattentively, requiring double clutching (using the clutch to synchronize the transmission internally for the next gear), they enter their element on track. If you shift them like an asshole and get your throttle timing right (lift as you move the stick for up shift, blip for downshift), then you don't need the clutch except to get rolling and it shifts like a sequential, and you can slam gears all day long, quickly and safely.
It's one of those things that needs to be answered when you are deciding what you want from the car - reliable violent operation on track, or quiet, smooth and easy operation cruising around on the street. Dog boxes, even without straight cut gears, sound like they're a pile of rocks by modern standards and require extra effort to operate (either mental to get your rev matching right or physical via double clutch). Synchronized transmissions are buttery and quiet shifting on the street but won't last being shifted quickly.
Or get a DCT and you can have your cake and eat it while receiving a blumpkin.
Last edited by TheJuggernaut; 05-02-2018 at 08:12 AM.
That's a pretty darn spectacular explanation, comrade.
I drove a 3.64 for a year or so while supercharged and liked it everywhere but on highway trips over an hour long. With 255/40/17 a 3.64 is more like a 3.58.
Quicktime
I probably misread his comment.
With the 5 Speed ZF....I didn't mind driving around in 5th with the 3.62 diff. Keep in mind the speed limits where I live are 80km/hr most places, and there are some 90km/hr roads, but I stay off of them because there are lots of cars. (Main access)
That functionality is already on the car, I just haven't been using it. I have cut on upshift, and blip on downshift available.
This one:
https://www.holley.com/products/driv.../parts/RM-4089
Don't mind the CAD...it looks backwards in a couple of images.
GForce will do an adapter plate on the transmission to fit any Bellhousing.
Bookmarks