You'd want to run right about the same indicated A/F on meth as without.

 

It is relative to timing retard and knock. For best power 12.5a/f on meth if you have no timing retard. If you are running up to 27* ign timing like Ivan, you are less likely to be able to run as lean. There is no reason to run low a/f ratio while far away from the knock threshold. Leaner is meaner.

 

What sort of exhaust temps are you seeing at 12.5 and mid 20*s for timing?

 

Leaner is also less forgiving and greatly increases detonation tendencies with any increase in load (e.g. 1-2 additional people in the car). 12.5:1 is very lean with or without meth injection and does not necessarily result in greater power. Additionally, ignition timing changes in that range affect power moreso than a few tenths of A/F.

I see no sound reasoning to run any different indicated A/F with meth than without.

 

Just swapped out to a tubular header and have not yet welded a bung. Unfortunately unknown. Typically knock would be present much over 900C* so I will assume it is under 950* maybe even under 900*.

I have run @ about 1000* C before. Timing numbers are usually affected at that point. We cannot assume that everyone is spraying the same volume of meth which is the most important factor. A/F's will be car specific.

Do yourself a favor and sign up on the derekdevises meth injection list an some others. You have to research from multiple sources, not just one and form your own educated opinion.

 

Interestingly enough appear to be right where you are. On a DD dyno (reads just a few % lower than a MD), I'm at 348whp/340ft/lbs, but it's running a TME turbo, and made best power between 11.5 and 12:1.

 

<--- 100% methanol injected+HKS 280's+stock turbo+turbotrix reflash=379 whp/372wtq on pump gas

 

That's great. However, for the benefit of those who read this and may not know better, those are Dynojet numbers. FWIW, 380whp on a 4WD Dynojet is ~330-335whp on a DD dyno.

 

i made 288 whp with turboback exhaust, intake, boost controller, fuel pump and reflash. I went back with alky and cams and front mount and made 379 whp. i think my numbers are pretty accurate, IDK about a 50 whp difference though. i went to the evo shootout when EVERYONE other then the race cars was running like **** and ran 12.6@112mph with a 1.87 60ft (garbage) and grinding 2nd and 4th. I prob coulda pulled a 12.0 or maybe 11.9 with a low 1.7 60ft and better shifting.

 

Whoa there. Easy on the benchracing. Have you gone 11's "off the bottle yet"?

I think avg expected gains are in the 30-35whp range from alky, and no improvement -more a substitute for racegas.

 

Yeah, I can't say how much I gained from the Alky. I guess I could power it off and figure out a pump gas tune, run it. Then figure out, from the mph, the power difference.

OT
But, I'll agree everyone was running horrible. I clicked off a 11.92 @ 117 and 11.95 at the E-town shootout. I couldn't get any traction on the start. I've since bettered that and have so far gone faster everytime I take the car out.

 

Your numbers, equivalent to ~330-335whp on a DD, are good enough to crack into the high 11s. Nothing at all shabby about that. The difference may be reflective of shortcomings in your previous tune.

I made back-to-back dyno runs with and without methanol. Tweaking the 93 oct tune gave 313whp - 292ft/lbs. With meth activated, power went up to 348whp - 340ft/lbs (~400+DJ whp). Boost logs show a difference of only 2psi at the torque peak, and ZERO boost difference at the power peak. Therefore, the peak power difference is due only to meth and ignition timing. Peak power was obtained between 11.5-12:1 A/F.

The difference in power with methanol injection due to ignition timing changes alone works out to 11%, which is significant. What I need now (like many others with this same setup) is a more efficient turbo.

 

the day i was getting tuned they had a prob with the software at first. So they tuned me on 21 psi and i was making 355 whp. after they fixed it i was running close to 30 psi and making 380 whp.

last time i got tuned i made 288whp. with cams, front mount and alky and retune i amde 379 whp. thats 91 whp gaines from cams, intercooler and alky.

the car will go 11's after a new clutch, tranny rebuild and cooler weather.