motordyne M370 manifold - round 2

Jordo!

That dip at the end can be tuned out -- it has to do with OEM tuning approaching fuel cut.

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Enjoy it. Destroy it.

98intrigue

Any suggestions on how to do that? Brian at EFI was tuning my car for over 2 hours and couldn't figure out how to alleviate the problem.

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esfourteen

Jordo has tons of great tips on tuning such as: "That can be fixed with tuning" and "you can tune that out"

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Build Thread | GTM TT Install Thread | Engine Build Thread

Endgame

not taking anyone's side, but that was a funny post!

Staples

When I had my car tuned, we were seeing some dips like that, so we added fuel to drop it down to 12.5 - 12.6 at wide open, added 2 degrees of timing and I ended up making 8whp more. I've seen a lot of the 370z and G37 tuned with UpRev and for some reason, they like extra fuel. 12.5 - 12.8 A/F seems to be making the most amount of horsepower / torque.

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'08 Infiniti G37s - Forced Induction Fed

98intrigue

Yes, my tuner said that he's seen 12.8 to be the sweet spot. I remember looking at the UpRev window and seeing the fuel right st 12.8, so I'm not sure why the graph shows 13.2.

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esfourteen

it was probably reading from the exhaust tip which usually reads a bit leaner

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Build Thread | GTM TT Install Thread | Engine Build Thread

Staples

That's absolutely correct... When you have cats and you're measuring air/fuel from the exhaust tip, more air then fuel is going to make it out of the car which is why the graph will read leaner because the tuner is compensating.

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'08 Infiniti G37s - Forced Induction Fed

98intrigue

Duh! Thanks for making me remember. This is my first time having my car on the dyno since my turbo G35, which I'd only see the data logs from my Utec that measured the AF right at the catless downpipe.

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