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Discussion Starter #41
The current mods already done are:
1) Go fast bits BOV
2) CPE delete
3) Cobb Accessport
AEM CAI (running SRI)/I have a Corksport too but its not on the car right now (hence the question about comparison)
4) Drop star rims (hate the chrome lip and may get that painted)
 

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I love the Corksport short shift plate I have on my Gen3 (which is obviously different) BUT do be aware that a short-shift mod does NOTHING about the realities of the shift itself, just your PERCEPTION of it on the lever end. (Also, most short-shift plates are fore/back only -- there are a few kits that also shorten the side throws but I'd avoid those as they materially raise the risk of a missed gate and that can blow up your engine.)

That is, you can't change what goes on in the gearbox. If you shorten the throw by changing the mechanical advantage ratios (which is what a short-shift kit does) then the force on the lever end goes up, as does the force on all of the linkage between the lever and the gearbox. So far so good; that's the trade off you "feel."

However, if you use that to shift faster that is ONLY safe for the gearbox itself IF you know how to and do properly rev-match in both directions, and virtually nobody does. Otherwise increasing the speed of the shift reduces by the same amount the time the synchros have to do their job. Synchros, contrary to popular belief are not supposed to ACTUALLY touch each other; they are supposed to act like bearings, in that it is the gear oil interface that is SUPPOSED to provide the synchronization. This is why GL4 fluid and NEVER GL5 is to be used; the film that GL4 forms on the interior surfaces is WEAKER than the brass material the synchros are made of, and thus the film shears FIRST, protecting the synchros. If you use GL5 the film is actually STRONGER than the synchro, and thus guess what shears? Yep. (This strong film strength, incidentally, is just fine and in fact preferred in an open or roller-locking differential since those parts are steel, not brass, and thus they're stronger than the GL5 film is.)

But, if you force the shift before the fluid interface can bring the dogs on the newly-selected gear into alignment then you go from full film lubrication to either boundary (bad) or direct contact (much worse) and metal-on-metal wear occurs. With a short shifter, since the throw is shorter, it is very tempting to shift much faster, especially if you drive like Speed Racer. But most people who drive like Speed Racer can't and don't also have the commensurate set of skills with their left and right feet when it comes to rev-matching on those shifts, and as a result you have a higher probability of buying synchros down the line.

The #2 synchro is the one that usually fails first in an MTX installed in a road car simply on driving dynamics; the RPM differential between 1-2 on a ratio basis is usually higher and, if you're accelerating hard from a standing stop that's the shift where speed-shifting has the potential to be the most-abusive.
 

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He said he accelerated in sixth gear. That is what I'd call lugging the engine, unless the rpms are high enough and you're being gentle with the throttle.
I did the math, considering the Speed 6 has 0.853:1 6th gear ratio, a 3.611:1 final drive, tires have a circumference of 2.001 m and that he stated he was cruising at 75 mph, the engine was running at 3,095 rpms.
I think there is enough torque there so I believe we can put this one to rest.

For reference, in 5th gear the engine would have been at 3.937 rpms, 4,249 in 4th and 5,570 in 3rd.
 

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I did the math, considering the Speed 6 has 0.853:1 6th gear ratio, a 3.611:1 final drive, tires have a circumference of 2.001 m and that he stated he was cruising at 75 mph, the engine was running at 3,095 rpms.
I think there is enough torque there so I believe we can put this one to rest.

For reference, in 5th gear the engine would have been at 3.937 rpms, 4,249 in 4th and 5,570 in 3rd.
The rpm is high enough to not cause much logging, but if you really stab the throttle hard enough I still think that would be enough to do the engine in.
 

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Sorry to hear that your engine went ZZB. If you have the funding, rebuild the motor with forge internals. Bullet proof it. Have the engine safely tuned and not to extreme hp. If your torque is near stock, go with OE clutch and flywheel. If you are pushing near 400 ft-lbs go Southbend or dual clutch Clutchmaster. good luck.
 

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Sorry to hear that your engine went ZZB. If you have the funding, rebuild the motor with forge internals. Bullet proof it. Have the engine safely tuned and not to extreme hp. If your torque is near stock, go with OE clutch and flywheel. If you are pushing near 400 ft-lbs go Southbend or dual clutch Clutchmaster. good luck.
Great advice, im glad someone mentioned it.

Dude, if you are swapping in a new engine, it means new ECU, and no access port. Im with this guy on the rebuild.
 

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Discussion Starter #48
Wish I could afford a rebuild. Its going to cost me over $4000 just for the engine, the new clutch, labor and taxes....Once the new engine is in I will have to do the access port install then? I ask because the Cobb Accessport was on the car when I bought it.
 

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Wish I could afford a rebuild. Its going to cost me over $4000 just for the engine, the new clutch, labor and taxes....Once the new engine is in I will have to do the access port install then? I ask because the Cobb Accessport was on the car when I bought it.
I don't know first hand but I would think that the Accessport would be fine. The ECU should keep its tune. If you were swapping computers then I would say yes, you need to install it then but this isn't the case.

Edit: come to think about this a bit more, I'm in the works of something that I will need to have my new ECU sent out to a tuner and they are going to delete the pats system out of it so I can use the engine in a different car. While he is there, he could give me a stage tune of my liking and then send it back to me. Once the ECU is programmed, it should keep its settings until changed again.

For your situation, you're only changing the engine. It will have the same everything else so there shouldn't be a need to redo the port. I would however keep whatever intake you had on it until the car is up and running. When you feel comfortable that the new engine is ok, you can try the other intake but it may need to be tuned for it.
 

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I don't know first hand but I would think that the Accessport would be fine. The ECU should keep its tune. If you were swapping computers then I would say yes, you need to install it then but this isn't the case.

Edit: come to think about this a bit more, I'm in the works of something that I will need to have my new ECU sent out to a tuner and they are going to delete the pats system out of it so I can use the engine in a different car. While he is there, he could give me a stage tune of my liking and then send it back to me. Once the ECU is programmed, it should keep its settings until changed again.

For your situation, you're only changing the engine. It will have the same everything else so there shouldn't be a need to redo the port. I would however keep whatever intake you had on it until the car is up and running. When you feel comfortable that the new engine is ok, you can try the other intake but it may need to be tuned for it.
I don't know first hand but I would think that the Accessport would be fine. The ECU should keep its tune. If you were swapping computers then I would say yes, you need to install it then but this isn't the case.

Edit: come to think about this a bit more, I'm in the works of something that I will need to have my new ECU sent out to a tuner and they are going to delete the pats system out of it so I can use the engine in a different car. While he is there, he could give me a stage tune of my liking and then send it back to me. Once the ECU is programmed, it should keep its settings until changed again.

For your situation, you're only changing the engine. It will have the same everything else so there shouldn't be a need to redo the port. I would however keep whatever intake you had on it until the car is up and running. When you feel comfortable that the new engine is ok, you can try the other intake but it may need to be tuned for it.
 

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I know this thread looks a little old, but I've got a 2008 Mazda 6 that was my daughter's car. It has a bad transmission, will drive in 1st & 2nd, reverse. Good looking car, grey, everything else works great. Will sell the whole car for $700.00.
She has already bought a new car, I don't have the time or know how to part this out. South GA.
New member, but reputable professional person.
Thanks, Steve email is [email protected]
 

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I know this thread looks a little old, but I've got a 2008 Mazda 6 that was my daughter's car. It has a bad transmission, will drive in 1st & 2nd, reverse. Good looking car, grey, everything else works great. Will sell the whole car for $700.00.
She has already bought a new car, I don't have the time or know how to part this out. South GA.
New member, but reputable professional person.
Thanks, Steve email is [email protected]
Steve Pope from NKY/St Henry?
 

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I know this thread looks a little old, but I've got a 2008 Mazda 6 that was my daughter's car. It has a bad transmission, will drive in 1st & 2nd, reverse. Good looking car, grey, everything else works great. Will sell the whole car for $700.00.
She has already bought a new car, I don't have the time or know how to part this out. South GA.
New member, but reputable professional person.
Thanks, Steve email is [email protected]
Um, don't know why you quoted me but I'm not looking for another Mazda for a project or parts car. Thanks though. I will be looking for a donor vehicle sometime next year but it's not a Mazda lol.
 
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