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:sigh:



Today was not to cold for the gas from the SDS EIC to atomize :tup:.
Which is a problem on really cold days (-18 degree celsius and below) since the intercooler upgrade and 2.5" pipes, the injectors fire but the engine leans out, even at lower boost with the injector gain all the way up the car just leans out, I pondered wrapping a 3/8 fuel line around the rubber coolant line going to the heater core to heat the fuel before it goes to the extra injectors, but I suspect the air at that time is so cold that it just freezes the gas on it's way through the charge pipe and when I do boost the car just spins in every gear anyway.
I guess due to the extreme cold weather and the fact the gas isn't atomizing and the car is leaning out, warmer gas is required.
From what I understand, cooling fuel helps lower charge temps and helps prevent detonation, but after a certain point cold charge charge air and cold fuel wont atomized thus leaning the engine out and risking detonation.
Warming fuel helps atomize it and more of it burns off, under ideal fully controllable charge temps this would be the way to make more power, but on hot days this could raise charge temps enough to risk detonation. PITA.

Today everything was just right I got the added HPR from the cold windy air, I had traction and gas to spare, the car was fast.

Well early this afternoon I was heading to a parts supply shop, just getting onto the highway, and started merging into traffic, I merged into the first lane checked my blind spot and gave it in second and merged to the next lane, shifted to 3rd and checked my blind spot to merge into the fast lane, I gave it full out in 3rd, (In that fraction of second) I saw 22lbs on the boost gauge and 11.6 on the wideband and BANG.

I thought I put a rod through the block or ripped the turbo from the manifold.

I put the car in neutral, turned of my signal cause I wasn't making that fast lane merge anymore, put on the hazards and coasted from the 110km/h I had achieved and merged back through the two first lanes of traffic and of the next exit, the whole time there was a loud knocking sound, it wasn't the engine, it sounded like the CV joint broke and was slapping around. I coasted till the car almost stopped and my co-worker hopped out of the passenger seat and pushed, got it on a side street and turned it off.
Checked the CV, it fine and there is no fluid leaking from the transmission, so I started the car and the sound was gone, it would come back when I released the clutch even in neutral, the car moved back and forth fine, maybe I broke a clutch puck off? or broke the release barring or pressure plate. If it was the diff the car wouldn't move or there would be a whole in the trany cause the Bang was that violent.

So I moved it and the grinding and knocking started again, I wanted to get it to a better location for the tow truck to get it and slowly drove with the hazards on, when I shifted to 3rd there was nothing, the gear is gone, 4th is there (was only going 30km/h never tried 5th).

The boost spikes and hits more then I set it to then settles at lower boost due to the crappy stock MX6 wastegate actuator and spring set up, the SDS can manage the spikes (seen up to 26lbs), I will soon have the external wastegate on and have much better control over boost and spikes, and I doubt that in track weather at similar boost (even with possible meth/alcohol injection) I wont make as much torque as in this cold, today during this spike.

This is the biggest potential problem I have seen so far with the F2T and high power. I know the engine has much potential left, the diffs are week but can last if driven properly even with lots of power to them. The 12V head flows plenty when ported and the blocks internals are good and strong, on the right tuning and with the right set-up I am sure the F2T can make a lot of power.

Will third gear be the downfall of the F2T, I will go to a stronger FWD transmission if I have to. But I'm kinda sad to think I might have to ditch the Mazda transmissions in my 88 and 89 GT's and move to something else.

I am also kinda sad I have to go to shop now and rebuild the transmission (on the car) so I can get to work tomorrow. It's really windy and getting colder by the minute.
I am just going to pull the end cap and center section, pull out all the transmissions internal, check them, wash whatever is salvageable and swap out the rest.

I might take picture if there is any interesting damage (hope not).
 

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That's quite the adventure... I'd be curious about potential transmission swaps, as there aren't any that fit our cars that I know of. Did you have some ideas in mind already?
 

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hmm.....the fe3 boys have definitely made more power on this tranny, and as far as i know only break third when slamming it into gear. i wouldnt be so quick to jump the gun on the tranny not being able to support said power (how much power you putting down in that unit?)....ive put atleast 5K miles on my tranny with +300whp\wtq and havent had any issues
 

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A friend of mine stripped all the teeth off 3rd once on 12 psi on a stock turbo and exhaust only. It happens...

Ive stripped 3rd twice on the mx3, but thats a little smaller gear than the H type. Still holds up to just as much abuse though :tup:
 
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The torque spike alone on the F2 with the stock turbo is enough to strip teeth, case in point my last dyno on 20 psi with the stock turbo showed 233 hp to the wheels but what got it there was the 343 lb/ft tq. 600-700hp Hondas dont make that torque which is why the trannies survive. Look at any of the T3 MX6 F2 dynos and you wont see anything near 350+ tq. linear dynos pwn in the long run, so do larger turbos with the F2T.
 

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This is the biggest potential problem I have seen so far with the F2T and high power. I know the engine has much potential left, the diffs are week

<snip>

Will third gear be the downfall of the F2T?
Hmm...I think there is a much simpler answer here than just, "this/that is weak".

(In that fraction of second) I saw 22lbs on the boost gauge and 11.6 on the wideband and BANG.

<snip>

The boost spikes and hits more then I set it to then settles at lower boost due to the crappy stock MX6 wastegate actuator and spring set up, the SDS can manage the spikes (seen up to 26lbs)
Yeah, I think this is a more realistic representation of why the failure occured. Its not the tools fault for being used in an application that it may not be best suited for...and a good mechanic never blames his tools ;)

Good luck with the rebuild.

Gavin
 
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