Cheap and easy efi 1.3 upgrades?

[cliferton]

So I just picked up a 1990. Eventually a swap will take place, but I'm going to sort out the suspension, wheels and tires, and get a couple other projects done. On miata 1.6 motors common cheap and easy mods. Are to advance the timing 10*, diy intake, and swapping the air meter for one from a fc rx7. I was curious if timing advance was common on the 1.3? Does anyone swap to a miata 1.6 afm? I know if intake is messed with the exhaust side needs to be opened up also.

[william]

Timing bump with higher octane,and the free air box mod.
Drill a bunch of 1/8 inch holes in the bottom and drop in a k&n.
Not sure how much this really helps but it's free if you don't get the filter.

[Advancedynamix]

I know a certain someone who made more HP on a dyno with a Festy VAF on his Miata ( miniscule amount) so don't bother with the VAF. I think they both use the same code VAF anyway.

Advance the cam timing, advance the ignition a tad, ditch the cat, 2" exhaust and adjust the VAF on a dyno to make up for the added efficiency from the exhaust. Any other work will be a waste of time since your swapping the engine anyway. Some people swear that drilling the air box helps hp, but I haven't seen dyno results from this.
Your best bet is the just put the 16v engine in as soon as you can, even on the stock tranny.

[F3BZ]

i seem to remember it said or was proven that the stock VAF could easily outflow the stock TB. i could go out and look but i'm thinking the stock VAF on my 1.8 escort has the same openings as the festiva VAF and will still outflow the 1.8 TB. even the miata forums discourage the taller RX7 VAF for all but the most radical builds.
drill the VAF regardless. the added growl at least makes you think its got more power.

[TominMO]

drill the airbox regardless. the added growl at least makes you think its got more power.

Fixed it.

[Advancedynamix]

^yup

[Dragonhealer]

"I think they both use the same code VAF anyway"

I can not find a difference between them, on the bench or dyno, except where the base setting is, 1.3 vs 1.6 Miata code "S" Festiva code "T"

"i seem to remember it said or was proven that the stock VAF could easily outflow the stock TB. i could go out and look but i'm thinking the stock VAF on my 1.8 escort has the same openings as the festiva VAF and will still outflow the 1.8 TB. even the miata forums discourage the taller RX7 VAF for all but the most radical builds. "

Yup.

[jhonmax12]

Regular preventive maintenance is probably the single thing you can do as a car owner to keep your ride happy and save money on repairs in the future. However, not everyone agrees on what preventive maintenance is, what you should do, and when you should do it. Let's clear that up, and give you some tips that'll apply to any vehicle.
………………………………………………….

PREVENTATIVE VEHICLE MAINTENANCE

[TominMO]

I know a certain someone who made more HP on a dyno with a Festy VAF on his Miata ( miniscule amount) so don't bother with the VAF. I think they both use the same code VAF anyway.

Advance the cam timing, advance the ignition a tad, ditch the cat, 2" exhaust and adjust the VAF on a dyno to make up for the added efficiency from the exhaust. Any other work will be a waste of time since your swapping the engine anyway. Some people swear that drilling the air box helps hp, but I haven't seen dyno results from this.
Your best bet is the just put the 16v engine in as soon as you can, even on the stock tranny.

i seem to remember it said or was proven that the stock VAF could easily outflow the stock TB. i could go out and look but i'm thinking the stock VAF on my 1.8 escort has the same openings as the festiva VAF and will still outflow the 1.8 TB. even the miata forums discourage the taller RX7 VAF for all but the most radical builds.

That's really interesting. One of the reasons I was thinking of going to MS on my Festy was to get rid of the VAF, for better intake airflow. I had assumed that the small opening in the VAF was a big restrictor to the system; but apparently not?

As far as drilling the holes, it made a giant difference in my 1990 Subaru Loyale, which had an airbox intake no larger than the Festy's, even tho it was a 1.8L motor! Above 3500 it really woke up after the airbox mod. Maybe not so much for Festys, but there may be some benefit; plus it's free and sounds cooler.

How do you adjust the VAF?

[Advancedynamix]

That's really interesting. One of the reasons I was thinking of going to MS on my Festy was to get rid of the VAF, for better intake airflow. I had assumed that the small opening in the VAF was a big restrictor to the system; but apparently not?

As far as drilling the holes, it made a giant difference in my 1990 Subaru Loyale, which had an airbox intake no larger than the Festy's, even tho it was a 1.8L motor! Above 3500 it really woke up after the airbox mod. Maybe not so much for Festys, but there may be some benefit; plus it's free and sounds cooler.

How do you adjust the VAF?

Pop the black cover off and there is a spring tension adjustment. There is also a bypass screw iirc. It's under the aluminum plug.

[Dragonhealer]

Pop the black cover off and there is a spring tension adjustment. There is also a bypass screw iirc. It's under the aluminum plug.

Charlie! You said too much or not enough!
Ok, for those who must, DON'T do this with out a dyno or fast wide band!
To get the cover off with out destroying everything, first use a hook pick or other small tool to carefully remove the silicone seallant around the edge of the cover, be careful as the cover is under the sealant as well and is very thin/fragile. Remove one screw holding in the electricle connector, don't lose it! Then put on safety glasses and gloves, holding a rag over the cover with your gloved hand, blow compressed air with a rubber tip blow nozzle in small dosses, just "bumping" the valve untill one edge comes loose, then hold that edge down and blow some more and thr cover will come loose.
At this point, MARK the face of the toothed adjuster wheel where the spring lock engages a tooth.
If you are careful with this delicate instrument, you can ease back the lock and move the toothed wheel. clockwise is leaner

[Dragonhealer]

Sorry about the typos,
please note that adjusting the AFM will change all other air/fuel adjustments some.

[jhonmax12]

Regular preventive maintenance is probably the single thing you can do as a car owner to keep your ride happy and save money on repairs in the future. However, not everyone agrees on what preventive maintenance is, what you should do, and when you should do it. Let's clear that up, and give you some tips that'll apply to any vehicle.
………………………………………………….

PREVENTATIVE VEHICLE MAINTENANCE

[Chobobulous]

Link is broken.

[TominMO]

Regular preventive maintenance is probably the single thing you can do as a car owner to keep your ride happy and save money on repairs in the future. However, not everyone agrees on what preventive maintenance is, what you should do, and when you should do it. Let's clear that up, and give you some tips that'll apply to any vehicle.
………………………………………………….

PREVENTATIVE VEHICLE MAINTENANCE

Huh? That's not what this thread is about.