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john vanlandingham

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SeanP
If the crack is big enough and upstream of the O2 sensor, it might throw you computer off in terms of air/fuel mix. I know nothing of these center diffs you speak of...that would denote more than two wheels driven, right?

Hey kid listen up here,, this guys is obviously an engine turnerz.

Now me, I would have probably blaabbed about how you can repair the cast iron and completely overlooked this. I probably would have thought of the between 8250 to 10,000 liters of 1000 degree plus exhuast every minute at no boost and upto double that on boost and thought about boring simple things like harness fires, and stuff. I probably would have totally overlooked the O2 sensor thing.. Gawddayum whodathunk air could crawl upstream with all that thousands of liters or hot exhaust streaming thru under some positive pressure....

See that's the value of these forums, you learn all sorts of things, it's amazing.

John, John, John, Oxygen WILL be drawn into the exhaust manifold, and give a false lean indication on the sensor and drive the fuel mixture rich, but only when in closed loop, and probably not at WOT. Go outside, start your car, and hold a sheet of paper to the tail pipe and report back...

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phlat65

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john vanlandingham

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SeanP
If the crack is big enough and upstream of the O2 sensor, it might throw you computer off in terms of air/fuel mix. I know nothing of these center diffs you speak of...that would denote more than two wheels driven, right?

Hey kid listen up here,, this guys is obviously an engine turnerz.

Now me, I would have probably blaabbed about how you can repair the cast iron and completely overlooked this. I probably would have thought of the between 8250 to 10,000 liters of 1000 degree plus exhuast every minute at no boost and upto double that on boost and thought about boring simple things like harness fires, and stuff. I probably would have totally overlooked the O2 sensor thing.. Gawddayum whodathunk air could crawl upstream with all that thousands of liters or hot exhaust streaming thru under some positive pressure....

See that's the value of these forums, you learn all sorts of things, it's amazing.

John, John, John, Oxygen WILL be drawn into the exhaust manifold, and give a false lean indication on the sensor and drive the fuel mixture rich, but only when in closed loop, and probably not at WOT. Go outside, start your car, and hold a sheet of paper to the tail pipe and report back...

Yeppers, could happen, maybe on decel when vacuum is present at the crack...mebbe...but we should all know a basic O2 sensor is largely trim, small adjustments, and not anything crazy such as a temp,MAP,MAF sensor. Unless heated and shorted internally most o2s have small effect on performance and running a bit fat requires an oil change after the event (needed anyway) but may well save the motor.

Can I watch JV sniff his tailpipe again???

John, I forget where we were at. Were you still gargling my nutsack or have we moved on from that?

FWIW, I have watched the 02 signals on cars with exhaust leaks and they can and will make havoc with trying to get an accurate tune. And yes, this is on turbo'd cars.

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SeanP
John, I forget where we were at. Were you still gargling my nutsack or have we moved on from that?

FWIW, I have watched the 02 signals on cars with exhaust leaks and they can and will make havoc with trying to get an accurate tune. And yes, this is on turbo'd cars.

It is true as far as drawing in extra o2, but it wont mess up the mixture on WOT, since most OEM ECU's (at least of that age) wont be using the o2 sensor at WOT. So no too much to worry about in this case.

But we're you trimming the ECU with a wideband, or maybe the ECU was a selflearning kinda thing with a wideband, then things can get veeeeery funny.

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Brgrds
Brian

I suppose we won't mention the 1.5 million EFI Ford V-8s with broken exhaust manifold bolts (or manifolds) that do everything from pulling 5th wheels to getting groceries without issue. Or the 1plus million inline or V-6 Nissans (turboed or otherwise) with broken manifold fasteners that clock along for more miles broken than they did before.

I'm with JV, the concern on this car will be from the heat escaping the crack. Kind of like ACPs Scion burning wiring and shift cables on Olympus. But if he can't schwing a waiver and logbook (making him squirm a bit here) it ain't a gonna matter much.

I know from direct experience that a crack in a gtx manifold will make it run funny at part throttle but when rallying who cares. part throttle. phpht. We're all macho manlymen who don't lift, or at least don't care if it runs funny at part throttle. As for getting that waiver, Gene is prolly right. I mighta ruined it for you some, Ross Foster ruined it much more, and them fellers what sold you that car prolly posted some stage times that suggest the old girl has some speed in her yet. I think there's a doowop tshirt says I got in the under7min club in one o' them and if anyone at RA has seen that shirt, they'll think that the gtx must be a giant killer. Specially if they've seen me drive. My cars all have a loose nut behind the steering wheel and are thus difficult under the best of circumstances.
Mark in your calendar this honeymoon phase of your relationship with this car and treasure the memory. Cuz you're gonna find out what "codependant", "dysfunctional", and "murder-suicide" mean! ;p

J--some old guy thinks he still has a shot at running Mt Hood this year

it didnt look like the crack was actually leaking exhaust, because it was on the little bridge that connects the two halves... but i do have the stuttering problem when at part throttle, so maybe i missed a crack. as far as getting a logbook, im thinking that if it takes more than 800 bucks to update the cage, ill just hit up some old logging trail, and mob the shit out of the car until i crash, then part out what i can, and start building a volvo 240 or an XR4ti... why? because fuck buying a used rally car, ive seen like 1 RWD rally car for sale in the last year, which is what i really need.

Well ya probably ought to plan a trip south so I can check the car. I honestly don't think we'll have any serious issue with it or the cage as it stands. I'm out of logbooks but should have some more by mid week. Doesn't much matter when you can make it down, I'll put the car on a hoist and go over it with you. I can't however do anything in the waiver dept, not my territory.

Don't mob it man, it's a good car, it just has personality and part of that personality is Christine. Trust Gene, he knows his stuff, don't worry, I got my cage updates for damn near beer money. If you gotta run NA for a bit just put the snail on the shelf and plan on turning the boost up when the time comes.

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heymagic
Well ya probably ought to plan a trip south so I can check the car. I honestly don't think we'll have any serious issue with it or the cage as it stands. I'm out of logbooks but should have some more by mid week. Doesn't much matter when you can make it down, I'll put the car on a hoist and go over it with you. I can't however do anything in the waiver dept, not my territory.

sounds like the offer of the year!

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SeanP

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heymagic
Well ya probably ought to plan a trip south so I can check the car. I honestly don't think we'll have any serious issue with it or the cage as it stands. I'm out of logbooks but should have some more by mid week. Doesn't much matter when you can make it down, I'll put the car on a hoist and go over it with you. I can't however do anything in the waiver dept, not my territory.

sounds like the offer of the year!

i most definitely will as soon as im done with this job. ive got a couple, maybe 3 more weeks left on this little island, then i can get the car stuff sorted.

Drive it around as much as possible is my trick.

I've had a lot of things fail, going to the grocery store.. (half shafts, wheel bearings, fuel pump, power steering pump, leaks of all sorts... etc)

GF reports my rally car is pulling to the right under braking (its getting pretty bad)
I noticed it coming back from gorman, but sometimes we just forget these little things ..



Edited 1 time(s). Last edit at 09/12/2011 06:56PM by A1337STI.

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WRCWRXSTI
im just wondering, should i really rally an open class car with the amount of experience that i have, or dont have?

There is a reason one of the sanctioning bodies won't let you run an open class car without experience.
(The intent is right while the application may not be ideal)

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Morison

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WRCWRXSTI
im just wondering, should i really rally an open class car with the amount of experience that i have, or dont have?

There is a reason one of the sanctioning bodies won't let you run an open class car without experience.
(The intent is right while the application may not be ideal)

so can i really just remove the snail and run open light? or will the car only get like 50 hp? how hard would it be to turn it into fwd or rwd?

oh and i can run open class with NASA RS rite? its just that they dont have any more rallies in the near future.



Edited 1 time(s). Last edit at 09/13/2011 01:32PM by WRCWRXSTI.

Not hard to turn it into fwd, just swap to the fwd gearbox and, what, I dunno, remove propshaft and let the rear end freewheel. Turn it into reardrive only is much much much more complicated and not worth even thinking about.