M20B28 Modified Engine Dyno results

Post Thu Mar 12, 2009 7:11 pm

Finally got it dynoed. Its my cheapsih rally engine.
Spec is 2.8 crank, HC pistons, Piper 270 cam, hot tuning 6 branch running motronic and Ant chip, no rear back box.

207 bhp at 6200 and 205ftlb at 4200, it was running rich in the mid range so could probably release a few more torques.

Need to get MS mapped now to see if i can a little more.

Post Fri Mar 13, 2009 10:02 am

You're over the magic 200horses on an M20 - nicely done

Post Fri Mar 13, 2009 1:40 pm

would release more ponies when mapped properly
Ms can give good gains over stock its just the hours of mapping
Well done fella

Post Fri Mar 13, 2009 1:49 pm

carannc wrote:Finally got it dynoed. Its my cheapsih rally engine.
Spec is 2.8 crank, HC pistons, Piper 270 cam, hot tuning 6 branch running motronic and Ant chip, no rear back box.

207 bhp at 6200 and 205ftlb at 4200, it was running rich in the mid range so could probably release a few more torques.

Need to get MS mapped now to see if i can a little more.

Nice going carannc, are there any deetails of your engine build/spec on here?

Post Fri Mar 13, 2009 6:14 pm

Nice, I need to get mine on the rollers at some point

Post Fri Mar 13, 2009 8:31 pm

gooner1 wrote:
carannc wrote:Finally got it dynoed. Its my cheapsih rally engine.
Spec is 2.8 crank, HC pistons, Piper 270 cam, hot tuning 6 branch running motronic and Ant chip, no rear back box.

207 bhp at 6200 and 205ftlb at 4200, it was running rich in the mid range so could probably release a few more torques.

Need to get MS mapped now to see if i can a little more.
Nice going carannc, are there any deetails of your engine build/spec on here?

Sorry - i was rather cribbing the info off here but here is the spec:
Std 325 block honed crosshatch and plateaud, 0.5mm off block face, STD shells, std oil pump, std sump, lightened flywheel, M20B20 rods, early 325 HC domed pistons. Std head, Piper 270 cam, kent cams vernier pulley (cam was a whole tooth out ! ) Piper cam followers, STD inlet manifold and injectors, 6 branch hot tuning manifold with lamda sensor, std centre box, extended pipes to reach rear valance, large air con radiator, peugeot 206 electric fan, std airbox, std ecu with ant chip. compared std chip on dyno and it had some weird flatspots but the ant chip smooths it all out. Was running quite rich mid range (10.5 - 11) but i will try and dial that out by checking the AFM temp resistance just in case there was a problem.

Oh and when it comes on cam it sounds awesome like a race engine

Post Fri Mar 13, 2009 8:42 pm

good result given the spec

good TQ vs HP too

for the midrange overfuelling, was this only a WOT run or did you run @ part throttle with load applied ? did the dyno show a power dip ??

I set my chips and MS to run rich @ 4 -4.4K in WOT, M20 can want to det there if run leaner, not all, but some.

post the graphs please dude , stuff like this always benifits those that tread the same path later

Post Fri Mar 13, 2009 9:19 pm

Was just a WOT run, sorry should have mentioned that, well several actually spent 2 hours overall. I will try and get the graph off the dyno computer. I was tracking AFR on my laptop as a safety precaution so dont have AFR accurate to revs. The test was to really check the spec so i can publish for the BMW rally challenge boys so they have an engine spec to build against.
Glad you mentioned that as i won't bother checking the AFM now and spend this weekend getting MS up and running above want to get the timing base settings sorted and a basic map using auto-tune, quite exited really and glad i have sorted Motronic just in case i make a balls up of MS

Post Sat Mar 14, 2009 3:37 am

Realize this is for a rally car carannc, but how would that cam shpe up in everyday driving.

Post Sat Mar 14, 2009 10:38 am

Its better than std at all rpms, so fine for road, i got the cam for free, there are plenty of others around and was a bit bemused it being so far out using a std pulley,(at least i know why it was so cheap) although i used a vernier it would have been almost perfect using a std pulley but one tooth further round. Car goes like stink and lights the tyres up as it hits the magic 3500 - 4500rpm

Post Sun Mar 15, 2009 10:49 pm

Good work there!

Post Thu Mar 19, 2009 12:24 am

nice
how smooth does the engine run (is it as smooth as an m20b25)?
does it still sound like an m20?
any video clips?

Post Thu Mar 19, 2009 8:10 pm

nice

Post Thu Mar 19, 2009 8:16 pm

Not as smooth as std as there is a surge in power when it comes on cam, sound is much much better, like a race engine, no video yet

Post Thu Mar 19, 2009 8:23 pm

Whats worth doing to a B25 lump? Have you read this in the chat section carannc.
Would be interesting to read your comments. Though maybe the fact that your cam was
for free, makes it slightly different.

Post Thu Mar 26, 2009 7:42 pm

Spent the whole day on my friends dyno, using Megasquirt with the beta Tunerstudio software was very easy. It took both of us to do the mapping. My mate operated the car and dyno, we used a portable lamda probe in the tail pipe as i had melted mine that was plumbed into megasquirt. I operated the PC and altered the maps. My mates dyno was amazing he could hold the map dead in the middle of each cell. I decided to map on std 95 fuel from tesco as i cannot guarantee to get quality fuel on a rally. My mates printer is still broken so i only have the headline numbers. Funnily the car feels slower as there is no surge anymore it just pulls like a train all the way up the rev range in any gear. I have some further tuning to do on the road like acceleration mixture and there is a jerkiness on overrun at 1500 revs but i am sure i can fix that. The problems i had were due to my lack of prep. As mentioned i melted mine innovate box (too close to the exhaust manifold and the MAP pipe kept collapsing under vacuum as it got way too hot so this needs replacing, the plugs i used were ditched was using W7 Bosch plugs, replaced with NGK 7's as i was getting the odd mis fire at low revs.
I retained the existing airbox but used drainpipe to extend to the throttle body which was replaced for a BBTB.

209.4 BHP at 6129rpm
215 ftlb torque at 4237 rpm

As you can see this is only a few more bhp but 10 more torques.

Post Thu Mar 26, 2009 7:53 pm

Quite common to see the peaks smoothed out once live mapped, and indeed it can feel slower due to the more linear output.

I did an Ms install on an M30 recently, the guy insisted it was slower, far from it in fact, however he plagued me with calls for 4 months so in the end I reverted the car back to stock moronic and gave him a full refund, sometimes perception outweighs anything else and I wanted out from under the plethora of calls, was a 1st for me

the jerky overrun can indeed be removed, once the TPS trigger is setup for closed throttle , play with the MAP sensor value to resume @ 10 KPa LOWER than the car naturally warm idles at, normally sorts any issues although with saturated high flow injectors a small bump will always be present, you can also specify a small amount of fule to be injected on the over run , again would assist with transients, and there's the hard part to get 100%.

Kudos again Sir, I love a bit of DIY ( o-er missus lol ! )

Post Fri Mar 27, 2009 12:14 am

Thanks for advice, i agree when you map it correctly it removes the surges but you really do feel it at the higher speeds. I took my mate for a drive and he thought i had a close ration box such was the relentless pull across the gears. I have to say the satisfaction is enormous, just come back from the pub after celebrating.