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Discussion Starter #1
hey all.. What the heck is wrong with my car? Just for the heck of it I wanted to try 89 octane on my car after running 91 octane nonstop since last year... The first time I stepped on the gas, a bad, bad miss started happening. I mean I'd be cruising, and my tach would register a 1,500 RPM loss every few seconds!! It's like losing 2 cylinders. So I quickly ran that tank out, put 91 octane back in with 12 ounces of Marvel Mystery, and bam, the miss is completely GONE and the car runs perfect.

What might that be indicative of? Fouled plugs? I'll check them tomororw
 
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somebody will be able to answer your question better than me. Maybe Retard the timing a little with the 89?? You probably run high(moderate) compression and alot of advance huh? The higher the octane the more advance you can run because the fuel burns slower, right?? I think that the lower octane is burning faster and causing it to fire to soon and "miss". Or im I wrong about this? I don't know much about engine's so somebody set me straight.

The reason I was posting:
I was just wondering if that 15.7 is for real?? Those inlines sure do make a bunch of torque huh? My buddy has a 50 chevy truck with a nova I6 with a carter 1 bll, and it will snap your neck if he gets on it. Prop's to you for going the I6 route. Build em well and they will last you Forever. They are fun and easy to work on too. 15.7 is DAMN good and MANY vmf'ers(me) would run alot slower with their mighty v8's. Keep up the good work buddy.
 

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Yes, I run high compression 2.3L Tempo pistons (about 10.5:1) and the timing is fairly well advanced. It most likely is timing related... The new double-roller timing chain I put on isn't quite as smooth as my old one, which is odd, probably needs to work itself out.

Yes, the 15.7 is for total real. I have a timeslip to prove it! My inline 6 makes more torque than a V8 with mild modifications does, dyno proven. I have those printouts as well. It could practically climb a tree if I wanted to... Of course, V8s breathe more and have more horsies to work with which is fine. An advantage with my six is the lighter front end - It handles a lot better than a V8 does. Plus the rearend really "squats down" and takes off when I floor it - I don't leave rubber too much or anything. The transmission does chirp second gear though which is ALWAYS fun.

Your mighty V8s might not run faster than me in their somewhat stock trim, but modify them as much as mine is modified, and you'll smoke me, and I know it. I'm proud of my six and no one can take tha taway from me. Not even you, gary_s289 /forums/images/icons/smile.gif
 

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We had our sweepstake 200 Mustang that had a milled head and it is very demanding. We basically have two octane ratings 95 and 98 (those are the higher ones of US (Mon+Ron)/2 ratings, can't remember whether it's Ron or Mon), it will only run well with 98. It is also very spesific about initial timing, we left that to 22 degrees. We were not very sure how much the vacuum advance advances. But 22 was a sweet spot, any less and the engine would shake badly and any more and it would ping.

It seems that increased compression makes 200 very picky about setup, maybe because of inherent bad in breathing and chamber/bowl design.

I totally agree what you wrote about the handling, when I first drove that, I said:" Oh, this baby has power steering." -"oh, no, it doesn't" was the reply. If six and V8 had similarly built "handling" suspension and all the usual goodies on six engine, six would beat V8 on slalom course easily.
 

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I don't know about CA, but here in the midwest 89 octane usually contains 10% ethanol and my 200 then runs the same way you mentioned. If I run either 87 with no ethanol or 92 with no ethanol it runs much better although the 92 runs the best.
 

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Sounds to me like you got some bad gas...Maybe some water in it, or something...
 
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