M54 Madness, the remix

[2mAn]

237whp is NOT bad at all! Nice

[hoveringuy]

Give in to our demands!

Fine...

Hit the dyno this morning. I tried some different VANOS profiles, mostly intake, and some slight timing adjustments. I found that it likes a little less intake advance below about 3000, it responded nicely to exhaust retard above about 4500, and I got a 2HP bump by advancing my timing 2 degrees across the board.

Unfortunately, I didn't do a run where I could incorporate all of those changes into the same run. The attached shows my baseline tune with 10 degrees of exhaust retard across the board, which made it suffer on the low end. It's compared against the pull when I first installed the motor, with the oversized and obnoxiously loud headers.

237WHP is decent considering I have OBD2 headers.

If someone could explain why I have a peak at 2500, a drop at 2750 and another peak at 3000 that would be swell.. I did get that to flatten out by having less intake advance.



Here's all the runs together:

[TheAxiom]

dyno, dyno, dyno. We demand dyno!!!

Give in to our demands!

[hoveringuy]

Public Service Announcement: If your wideband O2 sensor is more than a few years old, replace it! I'm at amazed at how well my wideband works again after replacing the sensor. It was behaving more like a narrow band, where it would register A/Fs close to 14.7 but nothing that was as it got richer or leaner.

Now, it's solid from like 11.0 to 18.0.

They're also really cheap now. like $50...

[hoveringuy]

Steve, you still go to Carb connection in Kirkland?

Yes.

[nando]

Steve, you still go to Carb connection in Kirkland?

[Jaker]

Woo Hoo!

[hoveringuy]

Dyno, dyno, dyno. We demand Dyno!!!

Getting closer, I promise! I have a fresh WB O2 sensor coming today to make sure my A/F is accurate.

I think my MAF curve is dialed-in for 14.7 everywhere, now I need to update the enrichment for higher fuel loads.

Car is running friggin' awesome!

[Jaker]

Dyno, dyno, dyno. We demand Dyno!!!

[ForcedFirebird]

There's a local company that makes large TB's that have a progressive linkage on them, mechanically making the throttle open less at tip-in, then opening more rapid as it nears WOT. Think it might be a Wilson Manifolds product.

[Sh3rpak!ng]

Can you elaborate? I have the UUC 8lb flywheel, my crank is 12lbs lighter than stock and I have lightweight pistons and rods. I am ecstatic with the throttle response.

Well, I read a bunch of reviews a while ago regarding larger TBs increasing "throttle response" and throttle sensitivity (some of those people didn't like it). But now that I think about it, that probably doesn't pertain to someone like you or I who actively search for ways to make our throttle an on/off switch :)

Sounds like you probably have a much lighter rotating mass than I do anyway. I am running a twin disc setup from clutchmasters which is a very light rotating mass, and also smaller diameter, though I don't have the extreme weight cutting like you have from the crank etc. The throttle response is fantastic with the super lightweight clutch setup but its also very grabby and tricky to modulate at low speeds. I drive the car a lot on the street still so I don't want it to be impossible to drive in traffic.

I am very interested to see how/if this effects the top end though

[Jaker]

my throttle response is already very sensitive with the very lightweight flywheel.

Can you elaborate? I have the UUC 8lb flywheel, my crank is 12lbs lighter than stock and I have lightweight pistons and rods. I am ecstatic with the throttle response.

[Sh3rpak!ng]

Curious to know what both of you find with the larger TBs.

I've been hesitant to go larger myself because as I understand, an effect of the larger TB is increased throttle response and my throttle response is already very sensitive with the very lightweight flywheel.

[Jaker]

I currently have a 68mm from Riot Racing on my build. I'm sincerely hoping it's holding back my top end power because I'm about to bolt on a 75mm VAC with opened up IM and hope its worth the effort!

[hoveringuy]

That's not a bad price to do that!

They did nice work. 3 day turnaround.

I figure 68mm is what BMW thought was the best size on the stock M54. By my maths, the extra 4mm is at least a 14% increase in area.

All 3.0 liter motors should probably have this size.