Cheap/Basic M42 Mods.

[decay]

The dbilas setup isn't cheap, but it is an easy install. Did mine myself and all I usually do on my own is basic maintenance like oil changes/brakes/etc.

It feels a lot like a hot cam does. Running mine with a MarkD 91-oct chip and an adjustable FPR.

[fiftytakedowns]

you ever driven an m50'd Car?
Did your gas mileage change at all?

[decay]

you ever driven an m50'd Car?
Did your gas mileage change at all?

I have not, but I'm sure it's not making that kind of power. OTOH the handling with a 4cyl and 225s is fkn awesome.

No noticeable change in fuel consumption.

[91 318is]

The dbilas setup isn't cheap, but it is an easy install. Did mine myself and all I usually do on my own is basic maintenance like oil changes/brakes/etc.

It feels a lot like a hot cam does. Running mine with a MarkD 91-oct chip and an adjustable FPR.

what spec did you get? Yours a track car or strictly street? I love my M42 and would like to keep it. I'd like to mod it without dropping big money on it.

[fiftytakedowns]

what spec did you get? Yours a track car or strictly street? I love my M42 and would like to keep it. I'd like to mod it without dropping big money on it.

If you have already got a chip, the next step would be to advance your intake cam 3 deg and retard your exhaust 2-3 deg.

puts the power in the middle, and it continues to the top. otherwise youll have to start looking for some regrinds, or Schricks
300 for rerginds 700 for scrhicks

[91 318is]

If you have already got a chip, the next step would be to advance your intake cam 3 deg and retard your exhaust 2-3 deg.

puts the power in the middle, and it continues to the top. otherwise youll have to start looking for some regrinds, or Schricks
300 for rerginds 700 for scrhicks

Are we talking changing cam timing on my stock cams? I'm a little confused. I'm curious what the specs are on your dbilas cams.

[decay]

Are we talking changing cam timing on my stock cams?

yes, the m42 has adjustable cam sprockets from the factory.

check my post #67 in this thread for ideas on what advancing/retarding each cam will do.

[91 318is]

yes, the m42 has adjustable cam sprockets from the factory.

check my post #67 in this thread for ideas on what advancing/retarding each cam will do.

Thanks man, I'll definitely look into it

[BlueBMW]

Here are the dyno results of my Mark D 93 octane install on my 91 318is if anyone's interested!

http://www.m42club.com/forums/showthread.php?t=11635

[e30pq]

Website Launch sale on M42 Coil On Plug kits ends 5/31.

Check out the special price at http://www,hqautosport.com

[fiftytakedowns]

Heres my post In Response to the mark D before and AFter.

107 HP before and
116 AFTER at 15:1 AFR


I have a NarrowBand AFR and It says I Run almost 14.7 maybe a little LEaner At WOT, according to many other people the cars do Run quite Lean at WOT.

I have 19 LB injectors in mine, I wonder if going up to 21 LBers would do the trick. Hopefully my FPR or soemthing like that isnt going bad, causing it to go lean....

I think you measure the TPS through The VOLTAGE across the thing, Mine reads 2-4.XX Vs from open to closed. I however have a bouncing AFR at IDLE from RICH to Lean, and the idle fluctuates. No vacuum leaks that I can find, however I am going to re-do all of the gaskets too.

I have mark D 91, 9lb JB flywheel, and COPs

I am going to Install a Vacuum Gauge pretty soon into the car, but not sure Which hose I could tap it into.

im starting to get really interested in Squeezing all the power Ican out of these motors through little tweaks ETC...

[e30guydownunder]

Heres my post In Response to the mark D before and AFter.

107 HP before and
116 AFTER at 15:1 AFR

Those are nice numbers. When I was at the dyno we popped off the AFM cover and played with the black dial to fine tune the AFR's. SOmebody had put the mustang injectors in my "new" engine...was running like 10.5:1 at WOT. We tuned it to 12:1 (there was a big lean spot further down the RPM I was trying to keep rich) at WOT and picked up over 20hp at peak.

I would not recommend bigger injectors without going to a dyno and tuning the AFM. You could probably get away with just tuning your AFM for somewhere around 12.5:1 at WOT.

[fiftytakedowns]

What if the Injectors are say, maxed out at that point? and can only support 14:1 thorugh 7K?

Im trying to look for some 21 lbers and that should be perfect.

Is it even possible to tune the AFm?

That little screw doesnt seem to do anything

[e30guydownunder]

I meant the black dial inside the AFM. Check out this link.

http://www.frwilk.com/the944/afm.htm

Make sure you mark the original position of the ring gear so you can return to stock.

I just had a quick look on an injector calculator and 17lb injectors will only just cover 140bhp so that could be an explanation! But I can tell you 21's are certainly rich :D

I would try dialing in the ring gear on your AFM first (hey its all but free), if you cant get it to improve, 21lb's and tune the AFM, job done.

[tjts1]

Heres my post In Response to the mark D before and AFter.

107 HP before and
116 AFTER at 15:1 AFR


I have a NarrowBand AFR and It says I Run almost 14.7 maybe a little LEaner At WOT, according to many other people the cars do Run quite Lean at WOT.

I have 19 LB injectors in mine, I wonder if going up to 21 LBers would do the trick. Hopefully my FPR or soemthing like that isnt going bad, causing it to go lean....

This is why I was running 22# injectors in mine. I still managed to get the same FE in closed loop but it doesn't get crazy lean at WOT. No matter how good the chip tuning is, once it gets past 85% DC it can't make up for the too small injectors.

But I can tell you 21's are certainly rich

I would try dialing in the ring gear on your AFM first (hey its all but free), if you cant get it to improve, 21lb's and tune the AFM, job done.

I can say from 2 years of using 22# injectors that its really not an issue. It passed the California 15/25mph smog check twice with these injectors and got excellent fuel economy. On my last trip from WA to CA before I sold the car it did 36mpg on 87 octane. I never touched the AFM. The mixture is only enriched when the ECU starts ignoring the O2 sensor at WOT and simply follows its internal fuel map.

I know it goes against everything we've read on the forums (hey just throw some bigger injectors in there and you're set), but in this case it actually works. The accelerometer on my ipod claimed 127 whp, 0-60 in 7.8, 15.9 quarter. you can take those numbers with a grain of salt. As far as I know, the accelerometer is pretty accurate.

Those are nice numbers. When I was at the dyno we popped off the AFM cover and played with the black dial to fine tune the AFR's. SOmebody had put the mustang injectors in my "new" engine...was running like 10.5:1 at WOT. We tuned it to 12:1 (there was a big lean spot further down the RPM I was trying to keep rich) at WOT and picked up over 20hp at peak.

I would not recommend bigger injectors without going to a dyno and tuning the AFM. You could probably get away with just tuning your AFM for somewhere around 12.5:1 at WOT.

I don't know if the version of the M42 they sold in Australia was with or without O2 sensor and cat but in California you really have to keep the car in a state that will pass emissions testing with both of those components intact. Fiddling with the AFM can affect that. As far as the whole 'mustang injector' thing, it really depends on what size injectors they put in your car. Do you remember the color injectors you had? Most people aren't actually using Mustang injectors. They're just EV6 bosch injectors of different sizes. Anything between 19-30# is pretty common. The color of the injector will narrow down that range.
cheers
Justin