rolling road tuning

[ukbiggles]

Hi Steve

I did ask him about this. Said he did classic car club days, where a number of us could go along on a Saturday morning and have a power test for £30 each plus VAT. Though it would need 10-12 of us to make him open up on a Saturday. This wouldn't include any diagnostic work to tune each Stag, as it takes a couple of hours each. So I'm not sure if this is valuable for Forum members or not. What do people think?

Cheers

Gord

[Nambo]

I fitted a Lamba sensor and fuel ratio gauge to my Stag, lets me see whats going on on actual use.
I have a Holley four block, I find it runs a perfect 14.7 when using the two smaller bores, but it goes way rich when I put my foot down and stays rich if I run the big bores.
I guess I can get a softer ramp for the thing that squirts rather a frightening amount of fuel in the hole when I open the throttle quick, but cannot work out what I can change to lean out the two big bores as they dont seem to have their own jets as do the small bores?

[Robmsharp]

Hi Nambo, which Lambda sensor did you choose, where in the exhaust train have you fitted it and what type of instrument display do you see the air/fuel ratio on?

Thanks
Rob

[Nambo]

Hi Rob, one of these kits http://www.innovatemotorsports.com/products/MTXL.php though I bought it in the UK, the price doesn't seem that much more than a tune up on the rolling road.
The Lamba sensor I will take a picture of later, it should be entering the exhaust pipe a certain distance from the head and at an angle so that it points down, mine is therefore near the gearbox. You get a threaded boss that you need to drill and have welded into the exhaust pipe.
You can see the instrument in the link, the following picture shows where I mounted it.

DSC00353.jpg

[Stagdad]

I fitted a Lamba sensor and fuel ratio gauge to my Stag, lets me see whats going on on actual use.
I have a Holley four block, I find it runs a perfect 14.7 when using the two smaller bores, but it goes way rich when I put my foot down and stays rich if I run the big bores.
I guess I can get a softer ramp for the thing that squirts rather a frightening amount of fuel in the hole when I open the throttle quick, but cannot work out what I can change to lean out the two big bores as they dont seem to have their own jets as do the small bores?

Going rich when you boot it is a good thing, gives more power and cools the engine. Sustained richness can be addressed by taking out the fixed jet secondary plate and buy a plate with mixture adjustment screws. Mike Heathcote on here has done this. Then of course you have power valves, spring weights for the opening of the secondary butterflies, and pump cams as well as the pump jet size you mention. There is quite a lot to understand tuning one of these.

when you think about it storms are actually a cleaver design giving different jet size depending on manifold vacuum.

[Nambo]

Going rich when you boot it is a good thing, gives more power and cools the engine. Sustained richness can be addressed by taking out the fixed jet secondary plate and buy a plate with mixture adjustment screws. Mike Heathcote on here has done this. Then of course you have power valves, spring weights for the opening of the secondary butterflies, and pump cams as well as the pump jet size you mention. There is quite a lot to understand tuning one of these.

when you think about it storms are actually a cleaver design giving different jet size depending on manifold vacuum.

I just tried messaging Mike Heathcote to ask him what I need and who sells them, message wasnt sent as "
The following users were not found:
Mike Heathcote"
Any ideas?



For Rob, I took a couple of pictures of my Lamba mounting for you, the cable I ran up the otherside of the gearbox tunnel so I could cut a hole with a grommet in the gearbox access plate rather than cutting a hole in the cars body itself.

The first picture is looking under the car from the drivers side, you can see the lamba is just in front of the square box of the overdrive, but do a Google search for optimum position from the cylinder head as I have free flow manifolds so might be different than yours.

DSC00685.jpgDSC00686.jpg

[Stagdad]

He is mjheathcote see post 8 on this thread.

Failing that try Real Steel

[mjheathcote]

He is mjheathcote see post 8 on this thread.

Failing that try Real Steel

Pm replied to Nambo, and yes Real Steel sell all the necessary bit and bobs!

[Robmsharp]

Thanks for all the info and pictures Nambo, think I'll be fitting one too.

[KOY 23]

Well worth it especially if you have aftermarket carb/injection.