Whats the best boost AFR

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v6bucket
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Re: Whats the best boost AFR

Post by v6bucket »

My 202 ran a 12.61@106 with .75 lambda & 1300°F exhaust gas temp using methanol earlier this year. When I was using petrol several years ago it's best mph (104mph)came at .88/.89 with 1300°F egt.
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VL400
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Re: Whats the best boost AFR

Post by VL400 »

Are you planning on putting air with your fuel :P 4:1 AFR is a crapload of fuel.

Back to the stoich below 100kPa thing, like charlay86 mentioned I would also be interested to see what the EGTs end up as and if they are safe.
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Holden202T
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Re: Whats the best boost AFR

Post by Holden202T »

thats the good thing about methanol :) aslong as its not hydraulic locking the motor its all good :driving:
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Holden202T
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Re: Whats the best boost AFR

Post by Holden202T »

i've been scouring the net trying to learn more about boost tuning, and i've found some varying results, but this is one thing i wanted to know, weather you should run a flat boost AFR table or slowly increase richness as boost rises, and i found this:
From http://www.efi101.com/forum/ wrote:For lambda, when tuning with petrol they like to run a bit richer, but the more boost you run, the richer the mixture needs to be like 11.8 (0.8 lambda) for 10PSI, 11.5 (0.78 lambda) for 12 PSI, 11.2 (0.76 lambda) for 14PSI or even richer. On one particular single turbo'd application by a well respected Rotary tuner AFR's were 11.0 (0.75 lambda) @ 16 PSI with EGT's of 982*C.
I guess the answer is, you need to have an EGT probe to really see whats happening.
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antus
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Re: Whats the best boost AFR

Post by antus »

and i guess that means we should find a cheap EGT sensor we can patch in to one of the aux. inputs of the '808 so we can get exhaust temp in the data stream.
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Holden202T
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Re: Whats the best boost AFR

Post by Holden202T »

working on it :comp:
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delcowizzid
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Re: Whats the best boost AFR

Post by delcowizzid »

all my egt sensors come with gauges online for around $35 bucks cheap as i mount them about an inch to inch and a half away from the head in the inlet runners of the manifolds
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Holden202T
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Re: Whats the best boost AFR

Post by Holden202T »

i'm thinking probe and controller to make it into a 0-5v signal so then it can go into the data stream :)
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delcowizzid
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Re: Whats the best boost AFR

Post by delcowizzid »

us $9.99 will get a controller with output as well as digital screen :mrgreen:
If Its Got Gas Or Ass Count Me In.if it cant be fixed with a hammer you have an electrical problem
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Holden202T
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Re: Whats the best boost AFR

Post by Holden202T »

link ? thats a fair bit cheaper than the one i was looking at.
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