View Full Version : Caught car on fire!!!!

05-08-2008, 08:42 PM

I have a 90 sc i have been working on for thi last 2 yrs. In the process I have put a fresh block with ported heads, ported blower, cam, headers, fmic, and a stand alone engine management.

I have work my heart out on this car once i heard this thing start up it was like having my first born. That happened 2 months ago!

Now to the present time i finally put the car all back togeather pulled it out of the garage to take it for a ride to putt putt around the house the air fuels where between 12.5 to 13.0 no more the engine temp never even went over 195 degrees but the thing was so hot it melted the glue in the hood to hold the vents in. THIS IS NOT GOOD! then i pop the hood to find th spark plug boot in the middle on the pass side was on fire. i forgot to mention i wraped the headers. This is not normal is it!

Now once i removed the plug boot from the spark plug it looked like it had been in a electric burn. It was real flakie and had a white look that when you touched it the boot would flake apart.

So this is the Question what could be the problem timing?
Does anyone have a idea on what my timing curve should be?

My mind is burnt out. I am not giving up YET!!! just looking for more input from some of the big guns.

I stoped by a local shop to see if he has any info or could give me a idea and all he told me was i did not build the motor call the person that did!!! NICE GUY RIGHT!!! but he has a point.

i attched a copy of my post with pics feel free to take a look as a reference.


Thanks for all your help

05-09-2008, 12:29 PM
Whoa! Sorry to hear about the troubles.

There are probably folks more qualified than I who will chime in... But it sounds to me like if the A/F ratio is good, then there is too little timing advance, which makes the exhaust very hot.

Too little advance = glowing hot headers
Too much advance = detonation, blown headgaskets, or worse
Somewhere in between = power

I tried searching here for some actual timing advance numbers, but I couldn't find them. I swear I've seen tables of this here before.

05-09-2008, 01:28 PM
Definately need pics of the spark plug wire that was on fire.

If it's by the exhaust, I'd check your timing map.

One of my friends had too little timing set on his beater car... He decided he would fry eggs on it's exhaust before he fixed it. They were quite tasty actually.

05-09-2008, 08:35 PM
after looking at the car today i think i really have a timing problem i am going to put a timing light on it tomorrow to see if its in time with the engine management. here is some pics. Do you guys have any ideas?

05-09-2008, 09:57 PM
Could have been a defective boot.

05-09-2008, 10:01 PM
was thinking same thing.

05-10-2008, 01:13 AM
The plug wasn't on the manifold by any chance was it?

05-10-2008, 01:27 AM
the plug was not on the maifold i have headers why do you ask? it was not touching tem in any way why?

05-10-2008, 01:56 AM
maybe to much heat

05-10-2008, 10:31 AM
Sounds like a good idea you have - confirming the timing with a timing light to make sure it's doing what is commanded by your aftermarket setup.

Also, assuming the timing is working as expected, where did you get your ignition advance values? I found this thread here where there is some mention of total timing at wot, and a download of an app that might show you the factory values that can be used as a baseline:


Also, one other thought is that (in a stock setup anyway) if a couple of plug wires aren't in the right place, a couple of cylinders could be firing way late, which would do the same thing. But I think you'd only see that on a cylinder or two, which isn't what you were seeing. Just a thought though.

05-10-2008, 03:36 PM
Are you certain that you had the plug wires on the correct plugs and that none of them were crossed up?


05-10-2008, 07:41 PM
how close is it to the headers now?(with the wrap) bc i had a problems like this, i had aftermarket headers and it was about and inch away and kept melting boots just like ur pic i got the boot sheilds to cover it and it solved the problem...

05-11-2008, 12:26 AM
In my opinion, the only power you'll get will be by adding a few degrees of timing. You can do this by pulling in the base file for your EEC and then changing your WOT advance vs. RPM by adding a degree of timing, then drive it and make sure your not detonating. Then give it another degree and check it out. You'll probably be able to run ( 16383.8, 28.5 )( 5200, 28.5 ) with no problem. I have run ( 16383.8, 30 ) ( 5200, 30 ) on 94 octane with a big FMIC and no knock. You'll just have to becareful not to put too much into it.

I found this in that thread. what does this mean 16383.8, 28.5 if the rpm was 16383 rpm i should run 30 deegreesof timing or am i wrong. I looked at it to night and got it running. After i gave it a good 5 deegrees of timing it seems to run better now i am at like 23 degrees of timing at 1500 rpm. i put a temp guage on the header pipe and got 440 degrees, that seems normal to me the timing is on with the mignets i installed. i have no clue from here.

05-12-2008, 05:45 PM
come on guys some one has to know what that means?

05-12-2008, 07:01 PM
You might want to spend some time looking at the settings from that post. Go to this post (http://www.sccoa.com/forums/showpost.php?p=430276&postcount=17) and download the exe to a temporary directory and run it. Then run setup.exe. Once it is installed simply open up the file a9u2.eec in notepad or something. These are the factory settings for the a9u2 eec.

Check out the WOT_ADVANCE_VS_RPM section. This is the factory advance curve when you floor it. So that might be a good baseline for you. Looks like they have a max of 26 degrees timing at 5000 rpm, for example.

But you'll also need to control the timing under other conditions when you aren't under wide open throttle. Check out the BASE_SPARK_TABLE values. These are a little harder to understand because the RPM and LOAD aren't shown directly on the table. You have to combine it with SPARK_TABLE_RPM_SCALING to determine the RPM, and SPARK_TABLE_LOAD_SCALING to determine the Load. For example (if I'm doing this correctly) at 2000rpm and 2.5% load, the timing would be 36 btdc.

Also, other things can take the values determined above, and tweak them. For example, if you are under wide-open-throttle, and your intake air temp (ACT) is 150F, it will pull out 4 degrees of timing via the WOT_ADVANCE_VS_ACT table.

05-12-2008, 10:53 PM
A melted plug wire doesn't tell you jack. You need to have the hood open and figure out what is getting so dang hot.

If the plug itself is getting hot, it means the plug boot has broken down and became conductive, possibly allowing the spark energy to to through the boot to the block rather than across the gap.

Are you sure nothing built a nest in the exhaust system causing excess heat?