anyone have a map with 280 cams and meth. Need some help

 

You really don't want to use someone elses map. You need to get it tuned if you don't know how to since every car is a little different. Another person map may be a decent starting point but I wouldn't suggest it especially without a wideband. The other thing is no two cars will have exact same mods so that changes maps from car to car as well.

 

I just wanted to use it as a starting point I do also have a wideband.

 

timing maps are usually ok to share with adjustments if they are not to extreme, but i would never use the same fuel map.

 

Honestly I just want to see someone elese fuel map for the 280s and the meth.

 

are you on stock injectors?

 

yes

 

well i just installed 272's on my car and for my fuel im runing a max of 12% more fuel at redline, just look at it like a curve. you should be able to run 12.3 AFR or so with Meth so i would add like 4 ramping to 9 or 10% on your fuel, i don't have my other computer, but i'll see if i can post some timing and fuel maps, just give me some time

 

I was under the impression that you should run lower AFR's... more around the 11.0-11.5 considering stoich for meth is around 7:1 compared to 14.7:1

Wouldnt that mean you would be running the meth part of the mix way too lean? I think the more meth you add, the richer the AFR should look.

 

anyone else?

 

keep in mind how the wideband reads.. Its calibrated to the remaining oxygen in the exhaust, therefore if your using an AFR gauge that reads 14.7 for stoich, adding alcohol and getting a stoich mixture, will read similarly.. Lambda readings are non-fuel dependent readings, thats why there is an alcohol and gasoline configuration setting on most gauges..

If your running pure alcohol as a fuel, and your gauge is still configured for Gasoline, I am under the impression that the gauge would still read around 14.7 for stoich, even though its in reality around 9.. Where a lambda value would read a value for rich/lean and not specific to the fuel type (which is less confusing)

In other words, keep in mind that its a blend of mostly gasoline, which also contains a little ethanol, plus a small amount of methanol if your mixing methanol, the majority of the benefit of methanol injection is in its ability to cool the combustion chamber by evaporating, and some gain by being a fuel.

Ever notice that if you switched blends from summer to winter (when they were doing it) when there was no ethanol, to 10% ethanol, and your fuel mileage went down about 10%? Its because the car is in reality burning a bit more fuel to maintain stoich at part throttle driving according to the O2 sensor.


Now back on topic.. Its not a good idea to use someone elses map.. even timing can vary GREATLY depending on mods, weather, engine, driving style..

 

hmm... well the two values are interchangable... I think the AFR is derived from the lambda number... therefore, if the lamda value drops (Or rises) it directly correlates to the AFR reading it shows. The sensor only measure O2 in the exhaust... I could see how running the car rich with meth could throw the readings to be leaner (High 02 content of fuel) but I think since it is being torched it will still burn the fuel and turn it into whatever meth break down into Im not an engineer by any means but I would reallythink just by spraying meth without changing the tune, is going to make it go ungodly rich (On the o2 sensor side).

It does make MUCH more sense to tune to Lambda as opposed to AFR since Stoich is pretty worthless in our cars when you think about it... at highway cruise is the only time you care.. otherwise we shoot for the 11-12 range and it would make much more sense to be looking at a number between .70-1.10 or that type of thing but oh well... this is the states and this is how most people have been tuning so why try to change it I will test how the o2 sensor reacts to meth once I get my car running again (Thanksgiving?). So Ill let you guys knows!

Back to the topic at hand... I would assume you want to see how much timing and fuel gets pulled when people spray the meth. The problem is you have NO idea on how MUCH meth they spray... when they start spraying it, their other supporting mods (Intake, exhaust, cams, etc...) but the biggest thing that makes it worthless for you specifically is the meth because it is such a HUGE variable (MUCH bigger than cams or an intake would change a tune). I mean the meth will make the tuning up to 30% fuel difference and a 15 degree timing difference... obviously alot more than an intake would do. It is even bigger of a change than if they mapped it with 110 octane as opposed to 93... in that case the fuel change is at most 10% and timing maybe 5 degrees in most cases.

 

Oh.. you also dont know if they are running say 25psi or 30.. you dont know when and if thier boost will taper in way close to the way yours does. Thier boost may drop off at 5k while yours holds till 6k. There are WAY too many variables to try to figure out, and in which case even if you did use someone elses it would just make it tougher for you to figure it out as opposed to you making your own. Honestly... you should probably get someone that knows what they are doing to tune it or just take the leap and give it a try. Its not that tough... but just think about exactly how your meth is setup... When do you start spraying, how much does it start with, how much more meth is gained per psi, and when does the meth cap? Just run the car hard once and look at the AFRs. Keep them underwatch... you should see a HUGE difference once the meth hits and which case try to make it closer to where it should be. Then go up a little RPM and keep doing so until the fuel looks good. Once you get there, look at the timing.. make sure it isnt too high anywhere on the map and start cranking the boost... it should let you go as high as you want it to. Watch for knock the whole time and start backing off the timing if you see anything.

 

I have just started to tuning my utec setup but i'm using larger injectors instead of meth as fuel assist. what are some of the benefits of meth, over just fuel?

Oh and I have the thing tuned great but I can't seem to find a happy meduim for idle mapping. rich at cold = perfect cold start idle, but stalls after hot run when warm. leaner at cold start= hard to start cold, but never stals after hot run at warm.

It's driving me crazy.

 

Do a search on alky or alcohol injection and you will find the answer you are looking for but bascially meth also has cooling properties which help supress detonation.