blown motor....From overboost? anyone ever have this problem

[nxpoweredsr20]

so i got my sr motor like 5 months ago and left the internals the same except the rocker arm stoppers and put a t4 hybrid turbo on it w/ 550 injectors, walbro, enthlpy tune, exc.....within ten minutes of driving in 4th gear at around 4k rpm i looked behind me with a huge cloud of smoke was comming out the exhaust......bad news ......anyways i blew apart the 3rd cylinder......anyone have this problem for the same or diff. reasons.....thanks...here is some pics....

[Hijacker]

how much boost were you running when it happened?

Whast I'm seeing there is a classic caase of not enough fuel for too much boost, bt given that you put some good injectors on there with a rom tune, it seems kind of odd to have happened.

[S14toRPS13]

Sorry to see that. Did you upgrade your MAF too? I want to push mine to about 1 bar. I'm not sure what I'm running right now until my boost gauge gets here. I'm running whatever the actuator is allowing me right now. Kind of scary. Let us know how much boost you were pushing.

[nxpoweredsr20]

ya it has a z32 maf on it......my wastegate has a 1 bar spring in it so it couldnt have been more than 14 psi....my boost gauge wansnt working and i didnt have the warning level set on my controller....thats what jeff at heavy throttle said....too much boost not enough fuel....but i put 550's on it with the rom tune and a walbro fuel pump so idk

[DrifterProdigy85]

I dont know. The enthalpy tune is usually pretty spot on. Only way to run lean is by having lower than 45psi fuel pressure. My tune runs around 11.5 AFR @ 50psi fuel pressure. One more reason to have a Wideband i guess. Im hoping your timing was set at 15*. Cause if it was advanced then that could have been the cause.

[Emperor_Tha]

Running too lean. From bad tuning. I see it often on eclispe turbo and evo over here at mitsu. Piston is all melted

[nxpoweredsr20]

how is would i know if it was in timing like you said ....i followed the instructions with thaving the piston at tdc and the timing mark on the cas...

[Kitswa]

T4 could = 500+ WHP - way too much for 550cc injectors.

WG spring will not limit boost if the vac lines are wrong or if EBC set too high.

-Bill

[S14toRPS13]

I see in your sig you have a nitrous kit. You wouldn't have happened to be using nitrous on this motor would you?

That's really strange though. I've seen 16psi on a SR with no other fuel supporting mods, but a Walboro 255 fuel pump do fine(yes, but not a good idea). Also I've seen 1.5 bar of boost on the same set up that you have except with a HKS GT2530 and that was fine.

[vtec-killer]

A friend of mine bended the 1st piston rod on his car ( sr20det datsun 510 ) he ran his car in 22psi by 30sec with an s14 t28, 550inj and low fuel in the tank

[Didderson]

Your timing wasn't totally set properly if that's all you did man. You're then supposed to use a timing light to figure the exact timing of the motor and like the guy above me said, set it to 15*bdtc. There is a how to set your SR timing in the articles section of nico.

edit: and I'm really sorry to hear you blew your motor. Good luck with the rebuild and make it better than ever this time!

[nxpoweredsr20]

thanks for all the help.....ya i will try the timing leght thing this time haha.......and no i didnt have the nx kit hooded up...im going to build it this time to support all the nx i can spray though .......

[Hijacker]

T4 could = 500+ WHP - way too much for 550cc injectors.

WG spring will not limit boost if the vac lines are wrong or if EBC set too high.

-Bill

That was my thoughts too, but without a boost gauge it's hard to tell exactly how much he was pushing.

There could have been a boost spike and you ran super lean.

Also, I'm surprised to hear your friend bent an SR rod. That takes talent as it's the rarest thing to break on an SR motor.

[nxpoweredsr20]

ya thats what i suspect too........any suggestions as to what size injectors and brands ? thanks for all the help

[Hijacker]

for over 350hp 650s are the bare minimum. You'd probably want to step up to the next size of 740cc though in case you end up pushing over 400hp

[codyace]

Detonation and PreIgnition rule!

[nxpoweredsr20]

which is ?

[DrifterProdigy85]

Well he hasnt said which T4 turbo he used. Thinking its a T4/60-1, he was only boosting 14psi so it couldnt have been much over 350hp on that turbo. Expecially if he doesnt have cams or intake manifold done yet. 550cc injectors have been able to make close to 400whp before with just increasing fuel pressure to 50psi. The problem wasnt with the tune, Ive used 4 different enthalpy tunes for the setups ive ran and all worked perfect. I believe the problem was your initial timing. When you set the CAS, you aligned the dot proper but that doesnt make the timing 15* BTDC. User error, it happens to all of us at some point. Chock it up as a learning experience.

[DrifterProdigy85]

Another thing to look into is Hardwiring your fuel pump. The S13 wiring doesnt carry enough power to keep the Walbro flowing at high rpm.

[nxpoweredsr20]

ya def. a learing experience....i only said t4 bc its a wet float turbo with ar.70 cold side and ar 63 hot side.....i need to look into how to time this thing better i dont understand all this 15 to bdc stuff...thanks for the input guys

[codyace]

ya def. a learing experience....i only said t4 bc its a wet float turbo with ar.70 cold side and ar 63 hot side.....i need to look into how to time this thing better i dont understand all this 15 to bdc stuff...thanks for the input guys

Not to be rude, but you have no clue at all what turbo you have.

Do you have any better engine bay pictures? It almost looks like you've got somethign t2 flanged due to orientation of the pipes.

The Enthalpy ECU didn't blow up the car either.

As said, base timing could have bene a huge issue. That, or if you did manage to get the CAS to line up correctly, you may have been a tooth off on a cam gear (effectivly giving you 19 degrees base)....which would lead to melt down.

As far as detonation/pre ignition...google it.

[nxpoweredsr20]

the turbo just doesnt have a name like a gt series or something because i bought it from a guy who works at a deisel shop......ill snap some pics of the turbo

[inkslingers13]

from what you said, it sounds like you could have a t3/60-1. a .63 and a/r70. but that sucks you car blew up man

[DrifterProdigy85]

So what you gonna be doing about a rebuild?

[nxpoweredsr20]

im doing cp pistons, eagle rods, 740 injectors, re tune, apexi head gasket, arp head studs, water pump, and new oil pan.....and while the motor is out im painting the whole car trublue from house of colors.....kinda like a 350zish

[codyace]

im doing cp pistons, eagle rods, 740 injectors, re tune, apexi head gasket, arp head studs, water pump, and new oil pan.....and while the motor is out im painting the whole car trublue from house of colors.....kinda like a 350zish

I would certainly find out what turbo you have, as that would give you a MUCH better idea of what we're all dealing with here....

[nxpoweredsr20]

thanks alot.......ill snap some pics tomorrow

[MagbeeA4]

that suck sorry dude i dont what that could be

[codyace]

that suck sorry dude i dont what that could be

DId you even read this thread?

[Hijacker]

DId you even read this thread?

I'm sure he didn't. He was just looking for a post to get his post count over 10. Notice all the threads he posted in were over a week old, and he just put a fluff post in.