Injector Upsize on SE - Is this normal?

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MINX
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Injector Upsize on SE - Is this normal?

Postby MINX » Tue Dec 22, 2009 6:21 pm

Ok - so this afternoon I am attempting to Upsize the injectors to Supra 315cc.

Never done this before.

So after an hour, I have the manifold off.
And can see oily/fuely/caramalised coating under gasket.
Is this normal? Or is it a problem?
Small amount of oil in upper part of manifold. Car doesn't us oil.

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Stu
Last edited by MINX on Mon Jan 11, 2010 10:19 am, edited 1 time in total.
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Injector Upsize on SE - Is this normal?

Postby timk » Tue Dec 22, 2009 8:29 pm

Yeah that's the oil vapour from the PCV valve. It only gets let in under vac so when the engine isn't under load.

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ASE05
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Injector Upsize on SE - Is this normal?

Postby ASE05 » Sun Jan 10, 2010 4:49 pm

Yup, problem, your car is fooked. I'll do you a favour and buy it from you for $5K :lol:
Sing that song, puff all night long.......

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bruce
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Injector Upsize on SE - Is this normal?

Postby bruce » Sun Jan 10, 2010 6:11 pm

That's normal. Very rare that an inlet is spotless.
Due to emissions that any oil vapours are fed back into the inlet to be burnt by motor (ie. a closed system). That's why catch cans (to catch the vapour) are illegal.

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Injector Upsize on SE - Is this normal?

Postby SPy vs. SPy » Mon Jan 11, 2010 12:16 am

MINX wrote:
Image

Stu


The truth is revealed why SE's are so wheezy, check out the bore size on those cylinders :shock:
Went for a drive and there were slow cars everywhere, why are NC's so common . . . must be NC = Normally Cardiganed.

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MINX
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Injector Upsize on SE - Is this normal?

Postby MINX » Mon Jan 11, 2010 10:18 am

Hey Spy - keep your SuPerfluous opinions to yourself.

315 Supra Green Top injectors in for nearly 3 weeks now.
Opinion - Not Sure.
I am not excited about them.
They definitely add 'power' in mid to high range (above 3500) with boost at 10-11 - providing really strong pulling power right up to redline with no pinging.
No noticeable loss of fuel economy.

However, they do take a while to warm up.
Not just getting the gauge upto normal, but it takes between 5 - 10 minutes to get the temp enough to really get them running smoothly. Until then, there is a bit of stodgyness on light throttle applications and changing gear, a little delay(overfueling?) before power comes on. So trying to simply drive smoothly upto 60 isnt as smooth and effortless as before.
Once they are hot though, very nice.

PS Also changed the PCV Valve to a 323 GTX Turbo Valve. (dunno if it made and diff)
Lakeside 1:02.94 Clubman 1:04.61 Sprint 1:00.81 Sportsman 1:04.27 National 1:28.36 WP 1:15.45 MtCotton 0:51.13 Symmons 1:12.2 Baskerville 1:08

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sprx3
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Injector Upsize on SE - Is this normal?

Postby sprx3 » Wed Feb 17, 2010 2:27 am

THE REAL BORIS wrote:Does anyone on here know the fuel rail pressure is for the SE? My Workshop manual says 53/61 psi but it covers the NA as well & I'd have thought they would be different.



Hey Boris,

NB's have 60 odd psi of fuel pressure, as far as im aware this did not change for the SP or SE...
want to join the mazda car club of australia?, for more info please p.m me
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Injector Upsize on SE - Is this normal?

Postby bretauto » Thu Feb 18, 2010 10:21 am

I have found that not all injectors are flowed at the same pressure, which can give a large difference in flow rate.
Also don't get to concerned about the US dyno figures, All the engines we have imported from the states ( N/A methonal burnning chev based) have been at least 10 - 20% down on the HP figure when dynoed in Aus, and on different dynos too. It is well know the the US has HP in the air.
Brett


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