White_FC

Whooooops..
thats all Ima gonna say.

Killed my poor lil motor last night, was giving it a bootful in fourth, wastegate line came off (my fault wasn't on there right), 18psi was reached, max duty cycle from the injectors came rather soon after that funnily enough.

Well i've been wanting to tear it down and freshen it up and port it a little for a while now, this just brought it forward a few weeks!

BTW, yes it was pulling freakin hard when it hit 18psi before it blew

Scott 89t2

460?? those are non turbo injectors. the turbo ones are 550

KenshinFC

man, what were you thinking? should've had some 720s or at least some 680s in the seconadaries if you're going to think about 18psi.

1987RX7guy

iTrader: (3)

did you not read? his wastegate line came off. I am guessing that makes it close dumping the booost into the intake.

Santiago

J-Rat

iTrader: (2)

The wastegate closing causes the turbo to boost out of control. Now the question here is, what the hell is with the 460 cc injectors?

1987RX7guy

iTrader: (3)

I hope he just messed up while typing this. lol

5 point whoa

jeez, can you say OVERKILL

White_FC

Haha lol

Car was an N/A, I turbocharged my 6-port motor, still using the std. injectors.
I'm suprised they didnt max out before 18psi .

Have some much bigger (1000cc) injectors sitting here.. they'll be going in before the rebuild is up.

And yes just to clarify, it was most definatly an unintentional 18psi excursion.

White_FC

BTW, before anyone asks, ECU is a microtech not a dodgy std. one


I was running 7psi without any dramas at all until that one little vac line fell off... :-(

5 point whoa

ohh, how many horsies are you pullin?

J-Rat

iTrader: (2)

Well that explains it... I am suprised you made it to 18 PSI.

Bet you were pulling like a mad man before it went pop....

NZConvertible

I think there's a lesson for everyone there...

Scott 89t2

don't turbo an N/A ??

White_FC

Never got it to a dyno

Now i just stripped everything off...
and i can feel all the apex seals are still there but it only has one good compresion 'stroke'..
very werid..

will tare the engine down in the next few days and keep ya'll posted.

now i just gotta decide how much I wanna port it

White_FC

Hmm whoops....
wasn't thinking before when I 'tested' for compression, as it turns out I only have one combustion that is dead..
Ie, 5 even pulses then one dead one..

What does this mean boys and girls? keeping in mind I can feel that all my apex seals seem to still be there? blown side seal?

any guesses so I know what to concentrate on looking at when I rip it out tomorrow/next day?

This should mean that I can reuse these housings if I still have good compression on some of the strokes yeah? (assuming they're within the wear spec obviously)

Aaron Cake

iTrader: (1)

Same thing could easily happen to a TII....

Anyway, that really sucks. At least your not too broken up about it...Of course, this means that while you have your engine apart, you must do the mandatory porting.

Black13B

iTrader: (1)

I must say that I'm impressed your not pissed off about it!

I can picture a few guys showing up and say "I hate RX7s! They suck! Mine detonated! And it's the cars fault, or the engines fault, not my lack of mechanics!"

Relisys190

iTrader: (4)

yeah man.. sucks about the car, but good keeping your head together. i guess these things happen right.

-Markus

"Get that puppy back on da' road running healthy again" CHEERS!

importboi22

happened to my first motor wastegate line melted went to 21psi racing a camaro =\

$150FC

two words:
twist tie

of course other things will work but there is an abundance of them in our shop so heh

88IntegraLS

White FC:

One dead compression stroke is a blown side seal. Although, you don't need anyone to tell you that. Just tear it down and look everything over like you would during any normal engine overhaul, and the cause will be obvious. You can't miss a broken seal.

White_FC

Yeah 88IntegraLS, I thought it sounded like classic symptoms of a side seal.

Any idea why a side seal would have gone? I didn't actually HEAR any detonation (that doesn't mean there was none though really)

Can't rip her out today, i'd better do my engineering prac instead but it should be out and appart tomorrow so we'll have to wait until then to see how much damage I did

And yes Aaron cake, will definatly be doing some porting on it while its out, not sure how crazy i'll be going just yet, but it will definatly be geting ported.

and I'm not pissed off about it at all because it was my fault that the line to the wastegate was not put on right.
mental note: always use he right size vac. hose and re-flare all the little nipples

88IntegraLS

Who knows why a side seal could have been damaged and not an apex seal. One likelyhood could be that the side seals sweep over the port openings, which are sharp on their closing sides, and if the side seal flexed while over the port opening it could have caught on the ridge. I think that is what did in Von's "godzilla port" engine, the enormous secondary / aux port cavity which would normally have had a partition between to support the side seals.

White_FC

Hmm yeah but I have stock ports not a 'godzilla' port hehe

strange.. was probably just old age, the motor has had a relativly hard life while N/A and turbo.

i've got a few scrap housings/side plates here im going to start practicing my porting on aswell.

I'm also thining a new intake manifold might be in order before the engine goes back in, more on that one later though.

You know I really wouldn't mind bridgeporting it, I hear it gives great mid range..

Fingers

You should have picked up adamlewis' guide to boostin 19 pounds on stock engine, stock injectors, stock turbo, stock intercooler He claims that he was more successful.