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-   -   Question about glowing header (https://www.rx7club.com/1st-generation-specific-1979-1985-18/question-about-glowing-header-501201/)

Dan_s_young 01-19-06 11:18 PM

Question about glowing header
 
Hey guys,
I was just kinda brain storming the last little while (doing engines in my mechanics class in college). When I removed the rats nest I removed the vacuum lines that goto the vacuum advance on the distributor like the step by step walkthrough says to...

So my question is, wouldn't the fact that the engine doesn't advance the timing in the high rpms cause the header to glow at the higher rpms becuase the timing would be off? It seems like no matter how I jet my carb that the header still like to glow cherry red after a couple minutes of driving... So I have pretty much turned my attention over to the ignition system. I have been running the timing with the L1 plug lined up with the timing mark on the front pulley (the one furthest clockwise).

Could the lack of vacuum advance cause this problem? Any other advice you guys can think of is appreciated!

Thanks!

IanS 01-20-06 12:48 AM

The vac advance only works until somewhere in the vacinity of 2K rpms. Not sure of exact number, but its for "getting going" and the mechanical (centrifugal) is for the higher rpms. You can hook the vac advance back up and see if it helps the glowing. I dont think it would change that much but you never know. I dont have that problem and mine are unhooked.

Mazda12AGS 01-20-06 01:00 AM

You are dumping way to much fuel into the header. You might just be running really rich or you have it lineed up with the wrong mark. I dunno

FB II 01-20-06 01:05 AM

it would be possible that if you had it lined up to the wrong mark then the timing would be massively retarded overall and would definately cause this. other than that, not having the vac advance hooked up will not cause the glowing. hell, i have set up a few locked distributors that never move from 10 or 15 degrees advance and the only time we've had any glowing header issues was from crappy spark plugs or being too lean.

if your timing is good, then the problem most likely lies elsewhere. what spark plugs are you using?

Kentetsu 01-20-06 03:20 AM

I would hook up those vacuum advance lines, unless there is a specific reason that you don't want to. Late spark would definitely cause the headers to glow, or loss of leading ignition altogether.

Dan_s_young 01-20-06 07:07 AM


Originally Posted by FB II
what spark plugs are you using?

NGK plugs and NGK wires, with MSD blaster 2 coils.

Glazedham42 01-20-06 09:37 AM

Sounds to me like you are running REALLY rich and there is actually additional combustion taking place in the header after exhaust gases exit the ports. Try leaning it out and see if that has any effects on your problem...

Jeff20B 01-20-06 04:54 PM

I'd have to say rich too. Or very retarded. Or possibly both?

KeloidJonesJr. 01-20-06 05:03 PM

overheating. this happened to my turbo manifold. I ran my car once and my turbo glowed. Thing is it had leaks. On the passenger side of the car there were holes, and when shifting gears, you can see sparks coming out from the exhaust manifold onto the passenger's feet.

onslaught_81 01-20-06 09:20 PM

ok not to thread jack but im guessing this means red glowing manifolds are not a good thing? my stock exhaust mani glows red all the time....time to do a tune up, and try to lean out the carb maybe

Glazedham42 01-20-06 09:56 PM

Yeah. You might also check your cats and make sure they aren't clogged if you have any. I think a clogged converter can also cause this to happen, if I'm not mistaken....

Dan_s_young 01-21-06 01:44 AM

I am running full racing beat exhaust, so the cats are not clogged, a full tune up has been done on this car a short period of time ago... So maybe the problem is the jetting of the carb.... Thanks for the help.

FB II 01-21-06 01:46 AM

see this is where a wideband and/or egt guage would come in handy :D

what emulsion tubes you runnin?

Dan_s_young 01-21-06 01:48 AM

Yeah, I was thinking of getting a LM-1, but since I am going turbo in the future I am not going to get a innovate wideband at this point, it would just be nice to have somewhat of an idea of what is going on with my engine....

36mm E tubes.

FB II 01-21-06 01:54 AM

hell if your going turbo in the future then getting the wideband now is still a good idea :D use it now and it will still be of perfect use later on the boosted setup. WOOT

also, are your chokes 36mm? i was thinking you would be running something like F11/F16/etc.. for e-tubes. it's been a while since i've messed with a sidedraft. i may be lost lol

Dan_s_young 01-21-06 02:17 AM

lol sorry I have been drinking... F-16 E-tubes right now, 36mm is my chokes... But for the future im going to do a T-II turbo swap into my widebody RX7

Kentetsu 01-21-06 02:38 AM

Pretty sure your timing is correct Dan? If so, I'd have to agree with running rich. However, it seems that the fumes would have to be about strong enough to make your eyes bleed if it was that rich (and no cats)....

FB II 01-21-06 01:35 PM

haahaha, not as bad as you would think ;)

now dan, i don't know why you would be using the F-16's. aren't they very fuggin rich?? ahahah when i used those on my old side draft it was too much fuel off boost :p: i would think the F-11's would be ideal for your setup. then just jet around that / mess with the air bleeds. arrrg, get the wideband! :D

Dan_s_young 01-21-06 01:45 PM

hey guys, thanks for the advice, tonight I will record what jets exactly im running... But as far as timing goes, it is lined up with the stock marks and the header still glows like crazy...

I thought before that a glowing header meant that the car was running lean?

FB II 01-21-06 02:02 PM

it happens on both sides of the extreme. hahahah, too much fuel and too little fuel from so much heat. either way it can happen, but it's hard to say without the tuning tools :p:


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