Air/fuel ratio meter installation

Use this forum for all your builds in progress.

Moderator: Moderators

User avatar
db
Posts: 8368
Joined: Sun Apr 18, 04 10:50 pm
Location: Paul McQueen , N Wales

Post by db »

I'm itchin to do mine mate but all the wedding arrangement blx has reached critical mass now- I can barely get thru the garage door without feeling the eyes of guilt upon me :roll:
Another 3 weeks then all will be calm 8-)

That'll give you time learn all about it then you can teach me :read2: :thumbright: ;)
No-one will believe you...
User avatar
Adrian Worman
Posts: 4376
Joined: Mon Aug 02, 10 1:23 pm
Location: Milton Keynes

Post by Adrian Worman »

Ok so drove in this mornin and tried all sorts of heavy engine loads in all gears and different eons, the idle is still pretty good at around 14, high vac part throttle gives over 15, cruising at 70mph gives roughly late 13's , so far so good but when I step on it I see no real change, maybe low 13's, too lean to make real power, I ought to be seeing low to mid 12's ideally.
So this evenin I will be mainly changing metering rods one stage rich, approx 4%, and secondarys two stages rich, approx 8%, idle mixture appears pretty good tho so I'll leave that, it's a piece of Bananarama! innit ;)
Jesus built my hot rod

72 Challenger
65 Barracuda
User avatar
Dave-R
Posts: 24752
Joined: Sun Apr 18, 04 11:23 pm
Location: Dave Robson lives in Geordieland
Contact:

Post by Dave-R »

Adjust the idle mixture to 14.7:1. On an automatic you need to do this with the brake on and the trans in drive. Manual geared cars can idle as low as 600rpm if you want. Automatic cars as low as 800rpm (in gear).

On auto cars the rpm should only drop very slightly when you put the car in gear. If it drops too much and you have to hold it firmly on the brake then the torque converter is not a high enough stall speed.

The 440 likes to be jetted on the primary (with the secondary side disabled) to around 13:1 at a steady rpm on the road using unleaded fuel. It will make best power at that.

You do need to be richer when you accelerate but you do that with the power valve and pump shot. So match the power valve (or whatever enrichment system) close enough to your idle or lowest cruise vacuum so that it enriches the mixture as soon as manifold vacuum drops slightly below that level.

If it still bogs when you floor it, check that the restrictions for the power valve (or enrichment jets) are large enough. Then start playing with the pump shot.

The secondary jets you need to size so that at a high constant rpm you still have 13:1. Then at the track see if going two steps richer increases your MPH. If it does then try another jet increse until you just find your max MPH jet size.

But leave the primary side at the 13:1 jetting.
User avatar
John
Posts: 1904
Joined: Tue Jul 21, 09 10:54 am
Location: Bishops stortford Hertfordshire MMA-369

Post by John »

Adrian Worman wrote:Ok so drove in this mornin and tried all sorts of heavy engine loads in all gears and different eons, the idle is still pretty good at around 14, high vac part throttle gives over 15, cruising at 70mph gives roughly late 13's , so far so good but when I step on it I see no real change, maybe low 13's, too lean to make real power, I ought to be seeing low to mid 12's ideally.
So this evenin I will be mainly changing metering rods one stage rich, approx 4%, and secondarys two stages rich, approx 8%, idle mixture appears pretty good tho so I'll leave that, it's a piece of Bananarama! innit ;)
Hey Ade, if yours reads the same way as mine, does going in to the 12'.s not mean its actually getting richer?
Lifes Too Fast But The Car`s Not, It even managed to miss the boat twice.
Now passed customs.
Now on route.
Now in posession.
Now costing me sh*t loads.
User avatar
Dave-R
Posts: 24752
Joined: Sun Apr 18, 04 11:23 pm
Location: Dave Robson lives in Geordieland
Contact:

Post by Dave-R »

When you "step on it" it should go very rich. But it should be the power enrichment system doing that. I think Ade was saying his is not going that rich when he floors it.
User avatar
Dave-R
Posts: 24752
Joined: Sun Apr 18, 04 11:23 pm
Location: Dave Robson lives in Geordieland
Contact:

Post by Dave-R »

I am not actually entirely sure how rich you need to go at WOT on the strip.

Mine was around 10:1 I think? Can't bloody remember now.

One variable is probably how much vacuum you have at WOT. With an unrestricted air filter and massive carb you are going to have only one or two inches of vacuum.
User avatar
Adrian Worman
Posts: 4376
Joined: Mon Aug 02, 10 1:23 pm
Location: Milton Keynes

Post by Adrian Worman »

Ta for that Daveman, at least I got my ideas in the right ballpark, just need to tidy up the idle mixture and then start on the metering rods.
Fortunately most basic jet changes and enrichment staging changes only require a minute or so on an Eddy carb :thumbright:

Yes John, when i stand hard on it right thru 3rd or even midway thru 4th its not dropping below 13 on a wide open throttle.....................and it Bananarama! should be................. wierd tho cos it always smells rich inside the cabin
Jesus built my hot rod

72 Challenger
65 Barracuda
User avatar
John
Posts: 1904
Joined: Tue Jul 21, 09 10:54 am
Location: Bishops stortford Hertfordshire MMA-369

Post by John »

Shooters making the smell maybe? Have you. 30 or 50cc pump shots?
Lifes Too Fast But The Car`s Not, It even managed to miss the boat twice.
Now passed customs.
Now on route.
Now in posession.
Now costing me sh*t loads.
User avatar
db
Posts: 8368
Joined: Sun Apr 18, 04 10:50 pm
Location: Paul McQueen , N Wales

Post by db »

Fitting mine today :thumbright:
No-one will believe you...
User avatar
Mick70RR
Posts: 1885
Joined: Sat Apr 02, 05 8:57 pm
Location: Birmingham

Post by Mick70RR »

Don't get too focused on 14.7 Ade. My car is almost undrivable if I tune it for 14.7. Here's a good article which recommends tuning a bit richer for better drivability.

http://www.enginebuildermag.com/Item/15 ... ation.aspx

Most petrol sold at the pumps these days contain 5% ethanol, the stoich value of a 5% ethanol mix is 14.4, so tune a bit richer and you should be seeing around 13.5 on the gauge.

My gauge rarely goes above 13 but I can't fault how it drives, any time I lean it off it feels slower and less responsive. When I floor the throttle, the gauge drops to around 10.5.
1970 Road Runner, 505CI, 4 speed, GV overdrive, 3.91 gears.
11.98 @ 117mph on street tyres
User avatar
Adrian Worman
Posts: 4376
Joined: Mon Aug 02, 10 1:23 pm
Location: Milton Keynes

Post by Adrian Worman »

I've experimented with a richer idle and cruise mixture and it makes the car much smoother to drive, a steady 70 mph cruise gives about mid 13 afr and idle is late 13's to just into the 14's.
At WOT the gauge gets to low 12's now and it pulls quite well, still feels a little strangled tho so I need to get some more main jets and go a couple of stages richer still............. gettin there tho ;)
Do us a favour Paul can you take some pix of your installation cos I can't get mine small enough to post up here :thumbright:
Jesus built my hot rod

72 Challenger
65 Barracuda
User avatar
db
Posts: 8368
Joined: Sun Apr 18, 04 10:50 pm
Location: Paul McQueen , N Wales

Post by db »

Well mine seems to be faulty :(

I powered up with cable disconnected, gauge reads 'E2'. CORRECT.
I connected the sensor in free air, gauge still reads 'E2'. WRONG.
I de-powered, disconnected the cable, re-powered and got 'E1'. WRONG.
I did the same again and now have no display at all VERY WRONG :cry:
I've emailed Innovate...
Attachments
AFR sensor angle.jpg
AFR sensor angle.jpg (143.08 KiB) Viewed 487 times
AFR sensor fitted.jpg
AFR sensor fitted.jpg (145.15 KiB) Viewed 487 times
AFR- drilling pipe.jpg
AFR- drilling pipe.jpg (160.66 KiB) Viewed 487 times
No-one will believe you...
User avatar
Adrian Worman
Posts: 4376
Joined: Mon Aug 02, 10 1:23 pm
Location: Milton Keynes

Post by Adrian Worman »

I know some one else had that fault, disconnect battery/ign power from the gauge, remove the sensor and start again............ nice pics of the sensor install tho Paul, the sensor is in exactly the right position to allow any water to drain off easily.......for those that are not aware, remember for every gallon of fuel you burn you produce a gallon of water, that's what rots yer exhaust mister :)
Jesus built my hot rod

72 Challenger
65 Barracuda
User avatar
db
Posts: 8368
Joined: Sun Apr 18, 04 10:50 pm
Location: Paul McQueen , N Wales

Post by db »

I've done that mate, even tried it on another battery off the car.
I'll try it again now, it's had an hour to think about what it's done...
No-one will believe you...
User avatar
Mick70RR
Posts: 1885
Joined: Sat Apr 02, 05 8:57 pm
Location: Birmingham

Post by Mick70RR »

I had to drop the exhaust recently to remove the gearbox so I had to disconnect the lambda sensor. While the box was out I fitted new speakers and had to switch the ignition on to test them. When I got it all back together after fixing the gearbox, the A/F meter didn't work. I had to unscrew the sensor again and do a free air calibration, then re- fit it and all was well again. If you switch power to the Innovate module for more than 30 seconds without the sensor fitted you will have to re-calibrate it.
1970 Road Runner, 505CI, 4 speed, GV overdrive, 3.91 gears.
11.98 @ 117mph on street tyres
Post Reply