M20 2.8 with motronic MAF conversion -Dyno'd!

[toby]

That's got loads of torque eh? Can I have a go please mister?

[goosiegander]

That's got loads of torque eh? Can I have a go please mister?

Yes indeed torque on tap, you are more than welcome to take it for a spin dude

[DmcL]

that MAF setup looks very similar to the one i came up with on my E30. was it an E36 MAF ant used? i used a volvo MAF on mine but both are bosch items, maybe slight electronic/size differences? also i notice there appears to be no retrofitted air temp sensor on ants setup.. any ideas what hes done to retrofit one or "map out" so to speak the input from the original air temp sensor?

heres mine as it sits now



i had the ICV relocated and the plumbing to/from it revised along with revised brake booster plumbing and the intake elbow replaced with a silicone hose and a large flexi pipe off the MAF, around the rad and to a filter behind the front grill. made more torque than the current setup but throttle response suffered with the long intake pipework. doesnt seem to be much if any difference up high in the revs tho.

[goosiegander]

that MAF setup looks very similar to the one i came up with on my E30. was it an E36 MAF ant used? i used a volvo MAF on mine but both are bosch items, maybe slight electronic/size differences? also i notice there appears to be no retrofitted air temp sensor on ants setup.. any ideas what hes done to retrofit one or "map out" so to speak the input from the original air temp sensor?

heres mine as it sits now



i had the ICV relocated and the plumbing to/from it revised along with revised brake booster plumbing and the intake elbow replaced with a silicone hose and a large flexi pipe off the MAF, around the rad and to a filter behind the front grill. made more torque than the current setup but throttle response suffered with the long intake pipework. doesnt seem to be much if any difference up high in the revs tho.

Thats interesting, my throttle response is excellent, as for the parts used you would need to ask Ant to confirm the exact spec,

Theres definatly more hp's in mine before thinking about high compression slugs,

To my mind a 'proper' n/a 2.8 build would be running naughty compression on forged pistons and/or rods,
IIRC The n/a record for a M20B28 is around 260hp but for a sensible daily that isn't going to try and kill you every time you boot it 230 to 240 would be nice,
Although saying that i'll eventually strap a charger to mine so disregard that lol!
-my two pence

[DmcL]

will have to change ur name to boostigander then

i noticed a definate increase in power/torque after i converted to MAF. i meant i had the MAF in there with a sealed feed and filter relocated to behind the grill. lost a little torque in the low revs changing to the short intake with velocity stack as pictured but seems to make up for that lower down loss with what feels like a slight gain up top.. probably just the short intake and velocity stack as im using the same pipercross sock filter i was using before. great little filter as it can be fitted so many ways since theres no base plate or anything for it.

tbh im hoping ant sees this and might PM me or post up some info on his setup. im particularly curious about the lack of air temp sensor if there isnt one integrated into the MAF he uses. i know by nature the MAF is meant to compensate for air temp changes but my line of thinking was that its a retrofit of a newer tech item to an older tech management system and it needed the temp sensor to work out airflow into the engine correctly.. i could be wrong there tho. was something about speed density systems vs another system of management (dont remember the name off hand) and basically the MAF based systems are one type and the E30's vane meter with temp sensor was another.

might disconnect the temp sensor on mine and see how she runs and if she seems to read the maps any different or in different places, etc. basically see if theres any change. i have the temp sensor wired in series with 1 of the pins on the MAF so its not gettign a dedicated air temp only signal to the ECU as theres some input from the MAF also.

ive also been tempted to try and peice together a MAP conversion to see what that compares like to the MAF conversion. seems to me to do a MAP conversion id only need intake air temp and the MAP signal to give the ECU enough input to work out volume of air entering.

[Ant]

Dmcl, read the 1st page dude, ALL the info is there for you.

MAF without air temp correction is a joke.

MAP sensors are typically the inverse of MAF/AFM, ie they are 5V @ idle ( 4.64 on the unit I'm using for some R+D) and 0.52 V @ full throttle( atmospheric pressure)

[DmcL]

wow.. MAP sensor conversion sounds like it would be no more difficult than the MAF conversion then. just a matter of basically flipping the values in the 1x8 AFM contsants map around the other way and a little tweaking to get it running right after that. might just keep my eyes peeled for a suitable MAP sensor in the local scrappers and see what i can do with it. be interesting to see which works best between MAF and MAP. would certainly be less restriction in the intake with a MAP sensor.

i must be blind.. i cant see if it says what the MAF is meant for anywhere

sounds nearly identical to what ive had to do to the fuel maps in mine.. im running 19lb injectors. having some issues with cold start AFR, i can lean them out with the stock AFM and 19's but seemingly not with the MAF and 19's for some odd reason. runs good apart from that tho, bit of fine tuning still to do, bit rich up top on the WOT maps and im also messing around with WOT ignition, have passed boundaries i previously thought would run into knock/detonation. after 2000rpm on the WOT ignition maps my lowest amount of advance is 32deg BTDC, max amount is 39deg BTDC and the 2 dips in advance u see on standard and most aftermarket maps is all but gone, values rise to about where the first peak is and stay up a bit longer and then fade back a little then fade back up peaking at 39deg BTDC in the higher revs. im experimenting with spiking fuel WOT maps higher at the end of the map and dropping ignition back at the end of the map as ive heard it can mean better pick up in next gear.. plus more chance of a flaming WOT gearchange

[Gunni]

Dmcl, read the 1st page dude, ALL the info is there for you.

MAF without air temp correction is a joke.

MAP sensors are typically the inverse of MAF/AFM, ie they are 5V @ idle ( 4.64 on the unit I'm using for some R+D) and 0.52 V @ full throttle( atmospheric pressure)

That is not the norm.

All the ones I have encountered are 0-5v and go low-high

[DmcL]

wouldnt be hard to test one out anyway.. just stick it in a vac line on the engine and test with a multimeter. seems almost too easy to do IAT + MAP having done IAT + MAF. definately something im going to look into out of curiosity at the very least. would be nice having an intake with no real obstructions between the filter and the TB.. or the BBTB when i get it back and installed

[Gunni]

I´m doing one for a forum member real soon.
It shouldn´t pose a problem as I´ve previously logged AFM / MAP curves before and they where not far off.

[DmcL]

wouldnt think it would be far off a MAF conversion providing the voltage range is similar. im too lazy to log stuff like that.. i end up peeking at tech manuals or whatever i can find or a good old fashioned bit of trial and error haha

[Hoobs]

Have mailed you Ant. I'm convinced so how soon can you fit me in please? Also, how long will you need my car as it's my daily and you're an hour or two away?

[steve_k]

what about a 2.9l m20 stroker with forged pistons, H section con rods, very naughty CR, head work, 270+ cam, 6 branch, BBTB, MAF set up, lightened fly wheel, etc?

now that would be fun

anybody got an idea on cost for the above???

[MillRat]

what about a 2.9l m20 stroker with forged pistons, H section con rods, very naughty CR, head work, 270+ cam, 6 branch, BBTB, MAF set up, lightened fly wheel, etc?

now that would be fun

anybody got an idea on cost for the above???

You have basically described my race engine, and it all cost me about AU$4,000 from memory (including the boring the block and the head work). We did all the build work.

[GeoffBob]

what about a 2.9l m20 stroker with forged pistons, H section con rods, very naughty CR, head work, 270+ cam, 6 branch, BBTB, MAF set up, lightened fly wheel, etc?

now that would be fun

anybody got an idea on cost for the above???

You have basically described my race engine, and it all cost me about AU$4,000 from memory (including the boring the block and the head work). We did all the build work.

Sounds like a simply stunning engine Michael

[MillRat]

Thank Geoff.

It really is a total blast to drive and I cannot recommend the modification enough.

If you, or anyone is interested, I have a build thread on another forum (it is a little long winded, but includes most of the progressive updates).
http://forums.eurocca.net/showthread.ph ... -rally-car

P.s. I apologise if I have hijacked the OP's thread.

[goosiegander]

P.s. I apologise if I have hijacked the OP's thread.

No worries dude, great build you have there,

I'll making a move towards A-Tech to adjust the cam timing slightly and another mapping session soon -hopefully in the next few weeks depending on how much time our 'Motronic Don' has spare,

Good thousand or so miles covered since rolling road and final adjustments, faultless with the current spec burned chip and a pleasure to drive

[AlpineAde]

Can't believe I missed this thread! Top work, Goosie; top work, Ant. It's definitely a step forward, losing that crappy AFM, in my opinion. I run the same set-up as MillRat.

[JazzMan]

Not been on the forum for a while, just seen this - very nice work chaps

[Jhonno]

Oops.. I completely forgot to pop my thoughts in here. I don't exactly frequent the 12v wrongness section though..

I was very impressed, drove the car before/mid/after MAF and the end result is superb. Great throttle response, power all the way round, and as can be seen, massive improvement in bottom end.. Sounds the tits on full chat also Much better option than an M30 swap imo. A great engine package, shame the decision wasn't made to stay N/A earlier so it could have been made higher comp and that bit sharper.. Mind, not that you'd know driving it.

I mean, errr.. I can't recall what it was like, I'll need another go to remind me..

[brian_s]

Excellent work bud what sort of costs would be involved to build a similar engine?

[goosiegander]

Excellent work bud what sort of costs would be involved to build a similar engine?

Cheers,

Off the top of my head approx £2500, assuming the first incarnation prior to MAF and mapping would be a good budget but then i do have a friendly local machine shop which helped no end...

[goosiegander]

Now for sale here: http://www.e30zone.net/modules.php?name ... c&t=224119

[Kedge]

Can i ask why you used B20 parts instead of B25? I had thought that the 2.8 crank would bolt straight into a B25 engine with the spacer mod.

[goosiegander]

Fresh 84mm bores and a spare block being handy dude

[Kedge]

Fair enough, so makes no odds which engine you start with then!

[HairyScreech]

Well, its a bit cheaper to start with a b25 as you only need add the crank, spacer and rods.
Starting with a b20 will mean a crank, spacer, block rebore and an 885 head.
Beyond that there is not much in it. A b20 is about £150-200 more expensive.

[Kedge]

So you do need the B20 rods? Certainly plane to do an M20B28 instead of going 24v in the future.

[Bullet_Ride]

Just to throw another M20 2.8L dyno plot into the mix. This is from a mobile dyno that was at the track a few weeks ago. The car was getting hot by the 2nd and 3rd runs which is why the torque dropped a bit



Relevant mods are:
Schrick 284 cam
Bavauto headers
single 2.5" exhaust
DIYPNP ECU

I figure if I pay for some dyno time and play with my cam gear and timing maps I can get close 200whp out of the motor. Then when I have some more money to play with I'll get the head ported and build a set of ITBS for it.

[downforce22]

Very nice. I recently build a 3.0L stroker with forged pistons and was looking into the WAR maf/ chip combo. Care to share what maf was used and how it was set up?

[Bullet_Ride]

Very nice. I recently build a 3.0L stroker with forged pistons and was looking into the WAR maf/ chip combo. Care to share what maf was used and how it was set up?

I’m not using a MAF because I’m running this kit http://www.diyautotune.com/catalog/diyp ... p-385.html
All you need is manifold air pressure (MAP) and intake air temperature (IAT). The kit has an onboard MAP sensor and you can buy an IAT sensor kit from that website. All you need to do is run a vacuum line to the control unit and install the IAT sensor somewhere along your intake tract. Then splice the two wires for the IAT sensor into the harness for the stock AFM and Bob’s your uncle

[bmwmaster]

Very nice. I recently build a 3.0L stroker with forged pistons and was looking into the WAR maf/ chip combo. Care to share what maf was used and how it was set up?

I’m not using a MAF because I’m running this kit http://www.diyautotune.com/catalog/diyp ... p-385.html
All you need is manifold air pressure (MAP) and intake air temperature (IAT). The kit has an onboard MAP sensor and you can buy an IAT sensor kit from that website. All you need to do is run a vacuum line to the control unit and install the IAT sensor somewhere along your intake tract. Then splice the two wires for the IAT sensor into the harness for the stock AFM and Bob’s your uncle

Hi,
my engine is much similar to yours. Sadly the head broke last week and now im rebuilding it.
Im thinking about to switch now to ms2 and as you write it is so easy with the diypnp-bosh-kit i think its the right thing for me.
But, how good is the basic tune in this kit ?
Did you a lot of tuning to have such a nice performance (like in your chart) ?
How did you tune it ? on street ? or dyno ?

[Bullet_Ride]

Hi,
my engine is much similar to yours. Sadly the head broke last week and now im rebuilding it.
Im thinking about to switch now to ms2 and as you write it is so easy with the diypnp-bosh-kit i think its the right thing for me.
But, how good is the basic tune in this kit ?
Did you a lot of tuning to have such a nice performance (like in your chart) ?
How did you tune it ? on street ? or dyno ?

The basic tune that they provide on their website is pretty good. My car had very little tuning when I put it on the dyno to get that chart (and I found out recently that my O2 sensor was out of calibration, my car was running far too rich when I did those pulls ). I had modified my timing map a little bit based on some maps that others with similar motors have posted online, but other than that all I did was play with the settings to get the car to start and idle smoothly, then run the VE Analyse Live feature that the tunerstudio program has (when you pay for a licence) while I drive around and it automatically smooths out my fuel table to hit the AFRs in the target ARF table. I still have to go in after the fact and do a bit of manual smoothing because some parts of the table are hard to hit long enough to let the software do its magic. Next year I will be paying for some dyno time so that I can play with the timing to get the most out of this old lump

[bmwmaster]

Nice, that sounds good !!!!!
I was afraid that i would have spend much money on dyno test time.
How difficult is the soldering when putting the ecu parts together ?

[Bullet_Ride]

Nice, that sounds good !!!!!
I was afraid that i would have spend much money on dyno test time.
How difficult is the soldering when putting the ecu parts together ?

As long as you've got a pencil soldering iron with a clean, small tip and some good solder it's a breeze.