blew my first n/a motor this way. drove it around took it for a hard run, parked it, came back to it and the rear rotor was blown.

just went tII, swapped in a rebuilt motor with 60K miles, full exhaust, ported wastegate, twin scroll removed, manual boost controller (set at 13 psi), msd 6a, msd wires, k&n intake, modified throttle body, electric fan, FD alt, rtek 1.7, 720cc secondarys, walboro 255, aem adjustable fpr (running a little over 40 psi).no emissions, premixing @ 1oz/gallon, hks ssqv BOV. tokico blue shocks/intrax springs, on 03 mustang cobra wheels with 235/40-17's up front and 245/45-17's in the back

just registered the car 3 weeks ago and ive been driving it and working out the little bugs. got it really nice last night and took it to the drags

bested a 13.70 made 14 runs throughout the night. parked it after a 13.85, it was running fine up to when i parked it. started it up 10 minutes later, sounded really flooded, tried deflooding, no help, pulled the plugs and sure enough no compression on the rear rotor.

i put not even a 1,000 miles on this motor (on top of the 60K it already had) and it was running strong up until it just decided to blow.

what am i doing wrong? i know i was running it hard but thats no excuse to blow the motor, even more so it wasnt blown when i parked it.

also. i need a s4 TII shortblock or rebuild kit now so pm me if you have something i may be interested in.

 

you tune the car yourself?

 

just ran whatever tune comes on the rtek 1.7. only thing i tuned was fuel pressure and i had it a a few psi higher than stock

 

I lost an engine the same way. Drove around. Everything was fine. Parked it. Started it a few hours later and only half the engine will pumping. I opened the engine up and found A LOT of carbon buildup. I concluded some carbon jammed an apex seal until it shattered. After I measured everything I rebuilt it with new seals, a good used rotor and a good used housing.

I would check into a WB02. You really shouldn't mod the engine and race without knowing how much fuel it's burning.

 

yeah i have an lc-1 wideband and haltek e6x ecu ready to go in the car along with a 60 trim to4e
i just wish i didnt need a motor for them..

 

Might have had something to do with the 14 runs you put it through. Yeah it may have less than 1k miles on it but any motor is going to take alot of abuse from 14 runs in one night.

 

So you were running 13 PSI from the stock turbo through the stock top mount?

 

im sure it was the tokico blue shocks/intrax springs.


lol jk. you need to make sure the tune is right. if that rear rotor was running lean it would have done some damage...

also what parts where reused from the last time you blew your motor? something like a sticking injector or a apex seal that got shot into the intake manifold or turbo causing damage to the new motor

 

So you have a wideband but you didn't have it on the car?

 

haha i included my suspension mods just because i flet they were slightly relevant to the times i was running in the 1/4.

and as for blowing a motor cause of 14 runs in a night thats bullshit. if a mustang can do it, so can an rx7.

yeah i have a wideband but im not using it, i got in the mail a week ago and was planning on using it once i put my stand alone setup together

yes 14 psi, stock turbo, stock topmount haha. fedex is dropping off my godspeed frontmount tomorrow. i just couldnt wait!

 

oh and the first motor i blew was when my car was non-turbo. i was not the one to rebuild the current motor

 

the rtek 1.x was meant to be used with a fuel controller like safc. you were probably running lean and timing too advanced. not surprised

it will be a lot more reliable on the haltech. It is all in the tune, conservative timing and lots of fuel

 

even so, it didnt blow up under load, it ran fine after goinbg down the strip, it wasnt until i parked it and shut it off, that something let go.. thats what i really don't get. live and learn though i guess

 

the problem is that you dont know the history of the motor.

there is quite a difference between a beat on 60k mile engine and a granny driven 60k mile engine. ideal would be somewhere in the middle

i agree with the carbon buildup theory. if you want to stop blowing engines then do it right. dont slap some greasy half dead 500$ engine in there. yes an overhaul kit is another 500$ but now you have to buy the overhaul anyway and probably at least one housing and rotor and quite possibly two irons and an eshaft. plus you now have to do an extra engine pull which means more trans fluid all over the ground and the possibility of stripping breaking denting scratching things while pissing off the wife/gf

 

why do you smell like sulfur?


Open that engine up and check it out.

 

i am a firm believer in doing things right the first time, i just had a little faith in the engine so a rebuild before even driving it wasnt a priority. and well lesson learned about running un-tuned either way.

i have another spare blown TII block, so i should be able to build something decent between the two i hope.

the plan as of now is small a bridgeport and rebuild

i ******* hate the smell of tranny fluid so much. luckily for me right now though, no wife/gf to give me a hard time about the car haha

 

You can pull the motor and leave the transmission... no gear lube smell.

 

The 1.7 is good for around stock boost levels imo. I'm running 720 secondaries with the rtek 1.7 at 8psi, and seeing high AFR's in the 13's, granted though thats with a bnr stage 1 turbo.

The 1.7 imo needs something like 850 secondaries and a safc for a good setup, but that's a lot of half-assed ******* around when you can just go to standalone and have one unit that isn't limited by a shitty safc tune.

 

yeah i guess i learned that the hard way. understranding i know i was to blame for blowing the motor, why did it blow when it sat, not under load? this totally baffles me.

 

How do you know the motor is blown? Did you do a compression test?

 

gotta pay to play

getting anxious cost you a motor when you could have already known that your fuel AFRs were lean with the wideband.

you should have at least a piggyback such as SAFC with the setup running beyond 10psi, Rtek isn't a magical chip that allows you to go to unlimited boost levels just because you upgraded the fuel system. anything beyond 10psi with even a chipped ECU is asking for a blown motor, if you aren't monitoring your AFR's.

 

could be timing, bad wiring. install the haltech with the new engine and make sure your CAS wires are shielded properly. the reason most T2s blow up is the stock ECU.

 

Templeton, i think its NH, no rx7's survive in this state.

-Jacob

 

there is no compression on the rear rotor. front is very strong pulses rear is nearly nothing. i get i killed it by running untuned now; im just curious as to what happens with these motors where they blow when like to fail when they sit.

 

the seals were already cracked when you shut down the motor but had rotating force holding them against the main friction side of the apex seal slot. once you shut down the motor the broken pieces relaxed in the groove and fell out as soon as you restarted the engine which stuck the rest of the seals. many times have i pulled apart motors where luckily the cracks were just such that the broken pieces remained intact within the rotor slot and did no major damage. the other cause is severely worn 3 piece seals, which the top section of the long apex seal rolls out of the rotor seal slot due to excessive clearances which is why almost no one uses 3 piece seals anymore.