how much diff will running on 7 cyl make?
how much diff will running on 7 cyl make? i just recently found out my mustang has been running on 7 cyl since the day i fired it up (about 1,000 miles and about 6 1/4m passes).
the car only went 12.40 @112 and was always running rich (wideband) even when just cruising down the highway and now that i pulled the motor i found out my #7 coil is bad (at least i think it is).
just wondering if anyone has actually seen an experience where someone was down a cyl and how much diff it made. i know 1 cyl is only 12.5% of the engine but there are also parasitic losses plus the tune being out of wack cuz the o2's would be reading wrong.
the car only went 12.40 @112 and was always running rich (wideband) even when just cruising down the highway and now that i pulled the motor i found out my #7 coil is bad (at least i think it is).
just wondering if anyone has actually seen an experience where someone was down a cyl and how much diff it made. i know 1 cyl is only 12.5% of the engine but there are also parasitic losses plus the tune being out of wack cuz the o2's would be reading wrong.
I waited months after tuning my formula (in sig) to get it to the track, car ran very very strong. Finally get a chance to get it to the track i borrow a trailer and go head out. Pull my car off the trailer, tech in, make my first pass. Ran a 12.6x? at like 110mph, very disappointed. Got back in line to run again and checked over my coil packs, happened to notice a spark plug wire had come off, no clue how or why it happened then.
next pass was 11.62@117.9mph
next pass was 11.62@117.9mph
I would think that if you ran the car like that for a while you would eventually mess up that cylinder. If the cylinder isn't firing because it doesn't have any spark then there would be fuel building up in that cylinder. Since it wouldn't be enough to hydro lock the engine it would just rock the rings after a while.
its an ls1, the ecu never showed a misfire, and im a little confused..... how would fuel build up in a cylinder? are you saying if there is no spark the exhaust valve won't open?
the motor is on the stand and im tearing it down to put it in my 78 malibu (w/a turbo), im more worried about the cylinder walls. if the #7 was washing down the wall im worried it may not clean up with an overbore if its scored real bad. i heard aluminum ls blocks cant be overbored that much. im planning on forged pistons and dropping the compression to i was gonna bore it have yet to research how much you can overbore them. and i dont really want to go with an iron block cuz of the weight, it is a drag car after all.
the motor is on the stand and im tearing it down to put it in my 78 malibu (w/a turbo), im more worried about the cylinder walls. if the #7 was washing down the wall im worried it may not clean up with an overbore if its scored real bad. i heard aluminum ls blocks cant be overbored that much. im planning on forged pistons and dropping the compression to i was gonna bore it have yet to research how much you can overbore them. and i dont really want to go with an iron block cuz of the weight, it is a drag car after all.
here's a link to a couple pictures i posted that show why i think im down a cyl
https://ls1tech.com/forums/generatio...test-coil.html
https://ls1tech.com/forums/generatio...test-coil.html
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its an ls1, the ecu never showed a misfire, and im a little confused..... how would fuel build up in a cylinder? are you saying if there is no spark the exhaust valve won't open?
the motor is on the stand and im tearing it down to put it in my 78 malibu (w/a turbo), im more worried about the cylinder walls. if the #7 was washing down the wall im worried it may not clean up with an overbore if its scored real bad. i heard aluminum ls blocks cant be overbored that much. im planning on forged pistons and dropping the compression to i was gonna bore it have yet to research how much you can overbore them. and i dont really want to go with an iron block cuz of the weight, it is a drag car after all.
the motor is on the stand and im tearing it down to put it in my 78 malibu (w/a turbo), im more worried about the cylinder walls. if the #7 was washing down the wall im worried it may not clean up with an overbore if its scored real bad. i heard aluminum ls blocks cant be overbored that much. im planning on forged pistons and dropping the compression to i was gonna bore it have yet to research how much you can overbore them. and i dont really want to go with an iron block cuz of the weight, it is a drag car after all.
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Verdad Gallardo i was kidding. i thought you were saying the cylinder would just keep filling with fuel causing a hydrolock situation. the amount of fuel i imagine should be the same firing or not. unburned fuel would just go ot the exhaust valve making the o2's read diff than whats actually going on.
and im really worried it did wash at least the #7 rings, wont know till i tare it apart.
and im really worried it did wash at least the #7 rings, wont know till i tare it apart.
I wanted to chime in on this one as well. First time out with my stroker build in ok air I ran a 12.0 @ 113. A plug wire was off on mine as well but I didn't find it until I got back home. Next time I was at the track in much worse air (over 2000 DA) I ran 11.2 @ 119.65. Probably would have run an 11.0 @ 122 on the day it went 12.0 on 7 cylinders.
Summary:
On a 500 rwhp setup you can lose around 100 horsepower with one plug wire off.
Summary:
On a 500 rwhp setup you can lose around 100 horsepower with one plug wire off.
#7 is the weak cylinder in the LS1 that always seems to get damaged as well. You usually see ring or piston failure there first. Seems it doesnt get the gresatest mixture of fuel and air since its in the rear and now with you driving it like that for 1000mi I would deffinately open it up and check. Trust me, I lost #7 ring gland on the piston before.
I wanted to chime in on this one as well. First time out with my stroker build in ok air I ran a 12.0 @ 113. A plug wire was off on mine as well but I didn't find it until I got back home. Next time I was at the track in much worse air (over 2000 DA) I ran 11.2 @ 119.65. Probably would have run an 11.0 @ 122 on the day it went 12.0 on 7 cylinders.
Summary:
On a 500 rwhp setup you can lose around 100 horsepower with one plug wire off.
Summary:
On a 500 rwhp setup you can lose around 100 horsepower with one plug wire off.
pretty close I put down 485 rwhp and on 7 it pit down 397rwhp
