2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

my car sounds like its got a SP, any way to really tell?

Old May 11, 2004 | 06:35 PM
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my car sounds like its got a SP, any way to really tell?

well i just recently finished my TII/NA swap. i used an S5 J-Spec motor. the car is set to idle at ~1700rpms right now cuz anywhere under 1500 it is really rough and wants to die. while idling it sounds like its got a lobe to it just like a mild cam in a piston car.

the car runs incredibly strong for the stock boost setting. i've also ported the heck outta the wastegate. anyways, what do you all think? is there a way to figure out if its ported or not without tearing the engine down and looking?

thanks.
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Old May 11, 2004 | 06:38 PM
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Blown seals make that lopey sound too. Do a comression check, then get your idle down to 750 and tell us how much vacuum its pulling at idle..
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Old May 11, 2004 | 07:02 PM
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thanks, i'll look into getting that done this week.
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Old May 11, 2004 | 07:03 PM
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oh yeah, i also have no smoke coming from the exhaust other then when i get on it then i have a little puff of smoke that probably is fuel.
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Old May 12, 2004 | 09:07 AM
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Pull the lower intake. You should find the intake runners smooth. You should also be able to finger them and feel how the port has been altered. Same with the exhaust.
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Old May 12, 2004 | 09:49 AM
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hmm dont sp's make the "brap brap" sound a lot more noticable?
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Old May 12, 2004 | 01:27 PM
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Depends on the size of the port. Most of the time, the idle is barely changed from stock. The "brap brap" is only noticable on very large ports...I've tuned some "large" street port engines for perfect idles at 800 RPM...Can't even tell it's ported...
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Old May 12, 2004 | 01:37 PM
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i got "large street port on all ports" from kevin landers.....when idling at 750.....you can hear the sexy brap brap vmmmmmmmmmmm brap brap vmmmmmm....

thank you mr zer0 cylinder hating aaroncake.
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Old May 12, 2004 | 06:11 PM
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well i think i found out why my car doesn't idle well under 1500. its spitting a very little bit of fuel out the tail pipe which leads me to believe that its running pig rich at idle.

after coming home from work while the car was idling, i put my hand after the canister and the exhaust was incredibly hot. is it that my car is running lean at about 1700 and really rich below that?
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Old May 12, 2004 | 07:20 PM
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running lean makes the exhuast hot. Generally running rich won't make the exhaust hot unless the excess fuel is actually igniting inside the exhuast system.
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Old May 12, 2004 | 08:55 PM
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alright, i just got back from a nice little drive and noticed that my alternator isn't keeping my battery as charged as it should. i'm using an N/A alternator on my TII motor and has been working till today. would a TII alternator maybe fix some of the idle since it would give more volts/amps to the coils which could then allow the plugs to ignite the A/F mixture better?
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Old May 13, 2004 | 01:46 AM
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no difference between t2 and n/a alts. Try an fd alternator.
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Old May 13, 2004 | 05:31 AM
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Check vacuum with a boost gauge.
If the intake is air-tight, you can guys if it's ported just by the vacuum reading at idle (speeds).


-Ted
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Old May 13, 2004 | 06:41 AM
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Lower then 20hg I'm assuming?
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Old May 13, 2004 | 07:31 AM
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From: n
20" to 18" a healthy stock port 13BT.
Anything lower than 18" is most likely ported.


-Ted
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Old May 13, 2004 | 09:08 AM
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maby check the voltage on the fuel pump if your haveing electrical issues ... would suck if your running lean all over, and have igniteing issues due to low current on low revs.

/bo

Last edited by gugge; May 13, 2004 at 09:13 AM.
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Old May 13, 2004 | 04:21 PM
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when we installed the Walbro 255 we rewired it so there shouldn't be any problems there.

today the damn thing wouldn't idle at all. i'm starting to think its a blown apex seal.
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Old May 13, 2004 | 04:34 PM
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Originally posted by Zer0 Cylinder
i got "large street port on all ports" from kevin landers.....when idling at 750.....you can hear the sexy brap brap vmmmmmmmmmmm brap brap vmmmmmm....

thank you mr zer0 cylinder hating aaroncake.
When I do extremely large streetports, they idle normally at 750 rpms. I can guarantee they are at least as large as your ports; the leading side of the side seals is completely unsupported throughout the port opening on both primaries and secondaries (10.5 mm from coolant seal inner edge)[the closing edge traced out by the leading edge must be completely bevelled or the seals catch the leading edge, compress and shatter], and the primary is larger than stock TII secondaries.
These engines were built with new rotor housings and 2 piece seals.

I don't really know who you are, so you can't blame this on any supposed anger towards you.
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