North American Turbocoupe Organization



timing question
Asimov Offline
Senior Member
#1
I recently turned my timing down from 12 to 8 (spout out) Is it possible for that change to make the engine idle low/die when hot?

I believe I blew off a vacuum line, and that is probably where my problem is. Especially considering that my vacuum dropped from 18-20 to 15... but I haven't had time to pressurize my intake system to see if I can find any leaks.

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-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 8 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 12 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
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Pete D Offline
Administrator
#2
Retarding timing can reduce idle, could even reduce vacuum but going down to 8* shouldn't be causing what you seem to have. Look for a leak.
Pete Dunham


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Jeff K Offline
Administrator
#3
The reduced timing isnt your problem. The IAC will go to a higher duty cycle to compensate for the reduced timing to hold the target idle speed the EEC wants to see.

When it comes time for the good old emissions testing here, I set my base timing to 8 deg, go take the test, and reset it to 15 deg after the test. Car idles / runs fine at 8 deg, just down on power.

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Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 04 Taurus Duratec (wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
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Asimov Offline
Senior Member
#4
Quote:Originally posted by Jeff K:
The reduced timing isnt your problem. The IAC will go to a higher duty cycle to compensate for the reduced timing to hold the target idle speed the EEC wants to see.

When it comes time for the good old emissions testing here, I set my base timing to 8 deg, go take the test, and reset it to 15 deg after the test. Car idles / runs fine at 8 deg, just down on power.


Yea, that was my understanding as well.

I am, however, curious why you run such high timing. It's my understanding that by reducing the timing you can run more boost (and get more power) without risk of detonation. Is this a mistaken assumption, or do you just have a good enough intercooler/setup that it's not an issue for you?

thanks!

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-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 8 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 12 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
Reply

Asimov Offline
Senior Member
#5
Just to fill everybody in, my makeshift vam->turbo hose had a large hole in it from the radiant heat from the exhaust manifold (when parked, moving there was enough airflow)

I've sinced covered it with insulated dryer duct, but may be exploring other options too.
-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 12 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
Reply

karnage Offline
Member
#6
I run high boost with lots of timing and have no issues with detonation.
84 TC with 88 hood LA-3 full 3" exhaust Rods header ported/polished big valve head schneider roller cam RW adj cam gear Kirban gillis at 20 # boost MSD ignition 255 lph Walbro full gauges
17 inch centerlines 944 front mount IC 80mm MAF
65mm tb-rotated intake on the way to 400HP
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martin0660 Offline
Posting Freak
#7
Quote:Originally posted by Asimov:
I've sinced covered it with insulated dryer duct, but may be exploring other options too.

There are several great options for the VAM hose HERE
http://www.mcmaster.com/asp/enter.asp?se...catnum=110

I was also at PepBoys the other day (I hate admitting that), and they have 3" plastic air intake hose on one of their displays. I was going to say in the ricer section ,butthat would be 2/3rds the store nowdays. It looked like it might work for this too. I considered picking it up to run from the VAM through the core support to mount my K&N up front. They even have a rigid connector to hook that up.

Bob Myers

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My 88 Thunderbird TC Pictures, Updated 3-19
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Asimov Offline
Senior Member
#8
Thanks for the link, bookmarked for future reference.

I've already went the ricer intake route. That's the hose that's on it now, and it's surrounded with insulated dryer hose. It has either developed a leak, or I have a new vacuum leak somewhere (which is basicly what a hole in the VAM hose is anyway.)

I went to 3 car parts stores and two hardware stores today. There is a _HUGE_ Lowes about 35 minutes away, and in their plumbing section I believe I found what I need to mount the vam straight to the turbo.

Several questions on that topic as well. http://natomessageboard.com/Forum1/HTML/013536.html


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-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 8 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]

[This message has been edited by Asimov (edited 03-30-2005).]
-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 12 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
Reply

Asimov Offline
Senior Member
#9
Well, what I have now should last till I get together all the parts I need for the SC IC coming soon.
http://natomessageboard.com/Forum1/HTML/013544.html

^- should I be proud, or ashamed that I used parts for toilets to fix my tbird?

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-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 8 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
-asi

1986 TC, 132k pretty well taken care of miles. k&n, [email protected], timing @ 12 (spout out), A/C delete. 3" Downpipe (no other exhaust... Whoever described that sound as a "pissed off tractor" hit the nail on the head)

[email pics to asimov at forced-induction org for sales/id/showoff purposes (free hosting)]
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