7MGE Dyno July 2017

[SRZMK3]

All the basics, AFM 6teeth adjusted, 15* advanced 92 octane. Pacesetter header, Cold Air intake, 2.5inch exhaust going to a HKS hipower, cat delete, one piece steel driveshaft.

90% humidity on a very hot day in oregon, made a crapton of torque but i figure the mid day conditions didnt help my NA horsepower figures.

lemme know what you think,

160whp 230lbfttq

 

[suprarx7nut]

That's a lot of torque!

 

[te72]

Not bad! Making that much torque and having only 160hp seems odd though, is that a misprint?

 

[suprarx7nut]

Not bad! Making that much torque and having only 160hp seems odd though, is that a misprint?

The chart looks like the numbers are correct, but torque took a nose dive at the top end, which explains the low peak power figure. AFRs are also dangerously rich through most the test. I'd love to get more info on that run and setup. There are a few odd things about it - at least to my completely unfamiliar eye.

CRE's NA 7M definitely didn't feel like torque fell off like that!!

 

[te72]

Hard for me to say, I prefer analyzing graphs plotted against rpm, rather than power against speed. That second one always seems weird to me.

Either way, looks like peak power is around 4000 rpm? That is really weird. OP, you say, "AFM 6teeth adjusted" and I'm not sure what you're referring to here. That may be why your AFR's are rich, tinkering with the AFM.

 

[7MGTEsup]

The chart looks like the numbers are correct, but torque took a nose dive at the top end, which explains the low peak power figure. AFRs are also dangerously rich through most the test. I'd love to get more info on that run and setup. There are a few odd things about it - at least to my completely unfamiliar eye.

CRE's NA 7M definitely didn't feel like torque fell off like that!!

Can you have dangerously rich? Looks like the torque falls of as soon as it switches rich at 82mph if you could find a way to get that back up to around 13:1 you would recover a lot of that lost torque.

 

[suprarx7nut]

Can you have dangerously rich? Looks like the torque falls of as soon as it switches rich at 82mph if you could find a way to get that back up to around 13:1 you would recover a lot of that lost torque.

Lol, no, that was a typo. Dangerously lean. My bad!

Do you want to run 13:1 under load though? I thought 11.5:1 was about the end of safe AFRs under load.

 

[3p141592654]

I would also check that the ACIS system is working properly. I don't know much about it, but it seems that if its stuck in the low rpm mode it might cause rolloff at the high end.

 

[te72]

Do you want to run 13:1 under load though? I thought 11.5:1 was about the end of safe AFRs under load.

I certainly wouldn't worry about it on an NA, if one were to start seeing excessively high EGT's, then there might be cause for concern. When my car was tuned, I was seeing AFR's between 11.5 and ~11.9 to one. Runs great and temps stay quite reasonable.

I would also check that the ACIS system is working properly. I don't know much about it, but it seems that if its stuck in the low rpm mode it might cause rolloff at the high end.

Ahh, good catch 3P! I forgot that the NA had the ACIS... The idea, in a nutshell, is that it has a longer intake runner for low rpm, and a shorter runner for high rpm. If I recall, the switch over point is something like 3800 rpm, which would correlate with my thinking the peak power appeared around 4k...

 

[7MGTEsup]

Lol, no, that was a typo. Dangerously lean. My bad!

Do you want to run 13:1 under load though? I thought 11.5:1 was about the end of safe AFRs under load.

13:1 is a pretty reasonable target with an NA engine they don't require anywhere near as much enrichment as a turbo engine hell some more modern engines run 14.6:1 at wot.