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Did some logging toda - tested 0.022 spark gap and resonator delete

4034 Views 12 Replies 5 Participants Last post by  XtremeRevolution
So after talking to vince yesterday, I started thinking hard using all the knowledge I have about automotive. I wondered if all the timing was being pulled because of the higher altitude and my spark gap. I've known drag racers with cobras who have had to run really low gaps to not only prevent blow out, but also to keep temps down and make more power. Seems backwards, but I went ahead and re gapped my plugs to 0.022. Stock was 0.025 across the board and I gapped them to 0.028 last week.

My plugs were starting to turn white (too hot) so I'm really glad I reduced the gap. When at 0.025/0.028 I would get on the throttle and around 3k it felt like timing was being cut. Now I don't feel that. At 0.022 I no longer feel that and my logs show that it isn't pulling so much timing now. I think I'll stay with 0.022.Additionally, I wanted to determine if the resonator delete really helped lower IAT's.

There was a big debate on XR's thread and I never saw anyone show any proof (although I'm sure someone has done so). So I went ahead and did it anyway.

(Green = AAT, Red = IAT)

No delete (2nd run)
View attachment 8286
With delete (1st run)
View attachment 8287

Looks like a 5 degree drop. That's significant IMO.As you can see the AAT's were higher when I did the first run. This is because I had been driving around. I went home, put a box fan on the engine bay while I inserted the ducting. I did however, drive the same route and drove the same way shifting at 5k in 3rd gear. I went East and then West.

I don't really see a point in spending $250 on a CAI since it's just pulling from the same place and isnt sealed up. Going to cut a 3" hole in the bottom of the air box like one of the other user's did. These are my finsings. I'm pretty satisfied with my changes.

I hope this encourages you guys to do you own testing now that we can see our logs.
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Its spiking because its the top of 3rd at WOT. I think the iat sensor is right before the throttle body so its temps after the intercooler.
Do you have airflow logs before and after the bypass?

If so please post them.
Without delete
View attachment 8297
With delete
View attachment 8298

Basically the same airflow. The Mass Air Flow Frequency is pretty much the same too.
Thanks, looks like the peak was a negligible amount higher without the resonator but nothing conclusive.
Air flow will be the same no matter what. The difference is how hard to turbo has to work to suck the air in and the temps. With the res deleted it gets cooler temps and doesn't have to work as hard. Now, the work load with vs without is probably also negligible but when I put it back in, I noticed there was more lag in the throttle response. So IMO it's very much worth it. It's free and easy to do with tangible benefits.
You can increase flow at the same boost level by removing restriction.
According to other members, our ducting isn't that restrictive. Except for the filter, there isn't anything in the way to restrict air flow. I'm ordering an AEM dry panel filter so I'll see what the flow is after the install.
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