HAS ANYONE A BORED OUT AIRFLOW METER

[rnd]

Hi I was thinking of boring out my airflow meter by 6mm as discribed in a rover engine tuning book by a man called Hamil. He says that Rover v8 engines normally run rich and boring the afm out will run the engine a bit leaner but .will not damage the engine as it was already rich. It is supposed to give 19% more air.It will only cost approx £15 by a pro to bore it out. Have never heard of anyone doing this but it sounds to good to be true. Is the truth out there

[mongoose]

I looked into this when setting out to modify the griff.It will be worthwhile,is what i was assured,as the AFM is very restrictive with its small bore(we proved this on a rolling road).What i actually ended up doing was junking the AFM all together,as even the larger ones are restrictive to making BHP.For that money you cant loose though,its far better than wasting money on a larger AFM.When you get to that stage you should be putting the cost towards a different ecu,which will then allow you to bin it altogether

[trackcar]

the std 5AM is compromising flow from 150bhp onwards, that's what we proved on mongoose's griff .. so even on 4 litre cars it's a restriction to hp.

[markh]

rnd said:

Hi I was thinking of boring out my airflow meter by 6mm as discribed in a rover engine tuning book by a man called Hamil. He says that Rover v8 engines normally run rich and boring the afm out will run the engine a bit leaner but .will not damage the engine as it was already rich. It is supposed to give 19% more air.It will only cost approx £15 by a pro to bore it out. Have never heard of anyone doing this but it sounds to good to be true. Is the truth out there

r


Ray I have a spare large one if you want it

[rnd]

Now people might take your statment the wrong way. I am a happly married man so I asume you meant the Jag airflow meter. Thanks but I dont really want to have to change or chip the ecu and you would have to do that with yours as i think it is the 20am. Alan has got 2 afm's bored out and has offered me one to try but I need to know that it will be ok fuel richness wise without tweeking ecu as it will be flat out all the time on track. Alan has got his done in antisapation of the bigger injecters you have for him and his car is up with the doctor getting all the work done now but he likes to spend lots of money but I have blown all mine on all my toys. Has anyone out there bored out the afm and did they have to chip ecu etc. By the way Mark where were you on Sat as we were wanting to here the beast running up the coast.

[vixpy1]

They don't all run rich, and they run rich for a reason, the theory is sound, but i see lots of chims runing 12:1 in factory trim, and thats about as lean as i'd go

If you do it, get the fueling checked before and afterwards..

[mongoose]

vixpy1 said:

....but i see lots of chims runing 12:1 in factory trim, and thats about as lean as i'd go

.Can you expand on that Vixpy please?

[vixpy1]

mongoose said:

vixpy1 said:

....but i see lots of chims runing 12:1 in factory trim, and thats about as lean as i'd go

.Can you expand on that Vixpy please?

Lots of Chims that I do power runs on are running an Air/Fuel ratio on full throttle of 12:1, i would'nt like to run mine any leaner than that. Rover V8's don't like running lean.

[jonnyb]

mongoose said:

vixpy1 said:

....but i see lots of chims runing 12:1 in factory trim, and thats about as lean as i'd go

.Can you expand on that Vixpy please?

With the factory standard chip some Chims are running 12:1 fuel air mixture, this is quite lean, and adding a 20AM AFM to improve airflow with out altering the fueling map or at least getting it checked could damage the engine.

At least that what I think he's trying to say.

[trackcar]

12:1 isn't lean, that's lambda 0.82 near enough (i think anyway, i always work of lambda cos it makes mapping so much easier) .. pretty much bang on what you'd aim for anyway.

[jonnyb]

trackcar said:

12:1 isn't lean, that's lambda 0.82 near enough (i think anyway, i always work of lambda cos it makes mapping so much easier) .. pretty much bang on what you'd aim for anyway.

So if you had 12:1 in standard tune what would adding a 20AM AFM do to the air fuel ratio if everything else was left unaltered?

[vixpy1]

trackcar said:

12:1 isn't lean, that's lambda 0.82 near enough (i think anyway, i always work of lambda cos it makes mapping so much easier) .. pretty much bang on what you'd aim for anyway.

true, its rich.. and its bang on what i would aim for too.. hence..

'i would'nt want to go any leaner'