Hello everyone, thank you for taking the time to read my post.
I have a 7mgte: rebuilt, forged, mhg, rebuilt, arp, machined properly, balanced, ct26 shimmed to 12 psi, steel ic hardpipe kit, 3 inch ddp, no exhaust.
about 35000 miles since rebuild.
To be upfront I drive her hard, but I don't over rev or keep it in boost for too long.
Daily Driver
The history:
Had an exhaust stud back out and had a head to manifold leak at #1 for a good 10000 miles. Has been fixed by my builder. Was a big enough leak to turn my normal 12 psi into about 8 max. Before all that follows, but didn't start immediately.
Started popping under takeoff about 6 months ago when I nailed first gear hard, no wideband at the time. Didn't think much of it, stopped nailing 1st on takeoff so hard.
About 3 weeks ago it started popping under very little throttle 10-15% in 1st and 2nd all the way into the RPM band and as I increased the throttle. I could get it to stop if I let off the throttle completely let the car nose dive then get back into it. Into 3rd I'd boost great and pull hard all the way to the top. Occasionally in 3rd under heavy boost and load like up a hill it would start popping when I was full throttle about 5000 or so RPM. My TPS at some point died and it
Since then I've replaced the factory IC pipes with the steel ones, good couplers, mostly t bolt clamps, changed the spark plugs, I use shaeff recommended "autolite 3923's gapped to .30", changed out my old MSD wires for some known good NGK wires, replaced and calibrated my tps, set my base timing to around 8 degrees of advance (at my engine builder's recommendation due to how much my head was shaved).
Now: Replacing that stuff has made my car idle great and run great for the most part. I still have light popping through 1st and 2nd but not super high into the RPM band. But if I get into full boost 11 psi or so at 85% or more throttle it pops like crazy in any gear. My wideband says about 11.5 to 11.7 at wot boost. My car idles perfectly at 14.7 and cruise is right around there.
Here is a link to a video of what is happening.
https://www.youtube.com/watch?v=9RBER6zhf2A
This is 3rd gear 60 mph or so.
Tomorrow I'm going to try a different coil pack. I'm not sure if this is spark related or fuel related yet. If anyone can help or has been through this I'd greatly appreciate it.
Thanks for reading all this!
I have a 7mgte: rebuilt, forged, mhg, rebuilt, arp, machined properly, balanced, ct26 shimmed to 12 psi, steel ic hardpipe kit, 3 inch ddp, no exhaust.
about 35000 miles since rebuild.
To be upfront I drive her hard, but I don't over rev or keep it in boost for too long.
Daily Driver
The history:
Had an exhaust stud back out and had a head to manifold leak at #1 for a good 10000 miles. Has been fixed by my builder. Was a big enough leak to turn my normal 12 psi into about 8 max. Before all that follows, but didn't start immediately.
Started popping under takeoff about 6 months ago when I nailed first gear hard, no wideband at the time. Didn't think much of it, stopped nailing 1st on takeoff so hard.
About 3 weeks ago it started popping under very little throttle 10-15% in 1st and 2nd all the way into the RPM band and as I increased the throttle. I could get it to stop if I let off the throttle completely let the car nose dive then get back into it. Into 3rd I'd boost great and pull hard all the way to the top. Occasionally in 3rd under heavy boost and load like up a hill it would start popping when I was full throttle about 5000 or so RPM. My TPS at some point died and it
Since then I've replaced the factory IC pipes with the steel ones, good couplers, mostly t bolt clamps, changed the spark plugs, I use shaeff recommended "autolite 3923's gapped to .30", changed out my old MSD wires for some known good NGK wires, replaced and calibrated my tps, set my base timing to around 8 degrees of advance (at my engine builder's recommendation due to how much my head was shaved).
Now: Replacing that stuff has made my car idle great and run great for the most part. I still have light popping through 1st and 2nd but not super high into the RPM band. But if I get into full boost 11 psi or so at 85% or more throttle it pops like crazy in any gear. My wideband says about 11.5 to 11.7 at wot boost. My car idles perfectly at 14.7 and cruise is right around there.
Here is a link to a video of what is happening.
https://www.youtube.com/watch?v=9RBER6zhf2A
This is 3rd gear 60 mph or so.
Tomorrow I'm going to try a different coil pack. I'm not sure if this is spark related or fuel related yet. If anyone can help or has been through this I'd greatly appreciate it.
Thanks for reading all this!
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