3.1L stroker w/ Dbilas

[DSP74]

Three questions:

1. Do you have flow numbers for your head?
2. Did you consider ExtrudeHone rather than the ITBs?
2. What's the diameter of each ITB?

I'm curious, since my guess is that the throttle bodies will outflow the capability of the head by a wide margin, even with that nice cam and header combo.

My understanding is the M20 ITB's they offer come with 45mm TB's. I think Alex may find that downsizing those will keep peek numbers up, as well as stop the low-midrange blah.
Someday. Someday.

[digger]

Cheers Digger, that will be very helpful since i will be using a Dyno Dynamics here in the US. Those are great numbers and I'm really looking forward to getting mine on the dyno for the tune. On my last 3.0L stroker I used the Dastek dyno when the car was tuned with the Unichip piggyback so I guess it's a bit hard comparing numbers from different dyno's :( Calvin's was dyno'd on the same Dastek unit too.

The dbilas setup is not available in the US....it was once sold through BMP Design with their own name on it, but I don't think they carry it anymore. Anyhow, just check out their site at http://www.dbilas-dynamic.de

387 miles so far.............dammmmmnnnnn

i find dyno dynamics a pretty inconsistant dyno (as far as readings across different machines) some read lower like Mustang and others read generous like dynojet, it depends which one you get making it hard to say where the numbers stand unless you compare it to results from the same machine.
The industry standard here is shootout mode (SHOOT_6 for NA 6 cyl)which locks in some variables such as ramp rate, drivetrain inertia CF etc so using it in this mode it becomes more consistant. Its very good dyno for tuning though.

It will be interesting to see what happens to the midrange and absolute peak torque as the 45mm TB are pretty big (48mm is an option aswell iirc), no question torque will be better after 6k. Its intersting that of the 4 M20 with dbilas setups that i know of each has gone for the schrick 288.

[B2702]

That looks awesome.

[fat325]

nice car man. gonna have to look in to the individual throttle boddies now i've seen yours :)

[elsabor67]

That is a awesome setup. Looks great. Gives me some ideas for the future.........

Definetly want to see those numbers when you strap it on the dyno.

[Chris E30 Cab]

Thanks fellas, it's alotta fun now that it's tuned :) and of course a real treat to look at LOL!

It's crazy how different this 288/288 cam feels from my other 3.0L stroker with 272/272.
At around 3000-3500 the engine just comes to life and screams to 6800rpm. Definitely
changing the rear silencer to something that's not like straight pipes cuz it's just obnoxious
sounding on the street. I took it out on the country roads and just had a ball........luckily
though, the Bluegrass Motorsports Club, just an hour north of me, is due to open in
09.............wOOT~! Now I just gotta sell enough cockpits so I won't feel so bad droppin
all that dough on a membership heheh.

Very happy with the tune, but surprised at how low the Dyno Dynamics numbers were....I
guess just dyno numbers though so no biggie. Besides the normal numbers and AF I did a
run in Shoot 6 mode for Digger to compare....hope it helps man! There are a few runs on there since some fine tuning was taking place.

According to the guy that tuned my car (who also works with the US distributor of Dyno
Dynamics and delivers/trains all workshops that purchase their dynos in US & Europe)
Shoot 6 mode is an inflated number to make people happy. This might be why Digger has
seen such big differences in numbers across different DD dynos....some in Shoot 6 mode,
some not? The dyno used for my tune, and they have many there, is the latest made by
Dyno Dynamics, along with the latest software release. Pretty cool to see they now have
a wireless hand controller unit now too.

HP & TQ at the wheels = 189rwhp 175ft-lbs


TQ & AF


HP in Shoot 6 mode

[nando]

yeah, comparing dyno #s from different dyno's is pretty pointless. it's too bad you couldn't have gotten a stock M20 baseline to compare to on the same dyno.

Also, it's more the shape of the curve that matters (I can't see the graphs unfortunately - firewall blocked at work). your engine probably makes a lot more torque in the low end, and a lot more power after 5500rpm than a stock M20, which pretty much falls flat on it's face after that point. So the peak isn't raised all that much, but the overall curve is much fatter which is what makes your car fast. The peak doesn't matter all that much. And I'm sure that schrick would flow pretty well to just over 7,000rpm if you wanted to play with rev limits. ;)

people who know = dynos are for tuning your engine
people who think they know = dynos are for bragging rights

if you go in expecting a certain (inflated) #, you'll most likely be dissapointed.

[4ce30]

this is soo gnarly...congrats

[CorvallisBMW]

Am I the only one expecting more than 189hp with a 3.1l, ITBs, a 288/288, big valves, MAF and standalone?

[BrewCity11]

Holy torque curve, more like torque line!

[nando]

Am I the only one expecting more than 189hp with a 3.1l, ITBs, a 288/288, big valves, MAF and standalone?

you didn't read my post did you :p

also technically, he has a piggyback. ;)

[Alpina]

Stunning project there,, you have done exacly what i wanna do to a M20

bravo,, superb


I went for a S38B38,, but what you did is what i wanted to do ((but i was in hunt for serious hp in NA mode and an oem BMW 6 cyl S-engine))

[z31maniac]

Holy torque curve, more like torque line!

Precisely. I bet that motor is a blast.

PS, whats up with fuel map? Your A/F ratio is all over the place.

[eurotrashm20]

HA I wondered who was driving the beautiful machine. Saw it in the shop one day when I was over that way picking up some paint. Heard what you were doing and was waiting to hear your how it was after tuning! I have seen ya a time or two driving around but have always been in the work truck so there wasn't even a chance of me catching up to ya. Nice build!! Look forward to running into ya at some point.

[gstuning]

fuel is not exactly spot on, you can see where power drops when it goes real rich,
might want to stay close to 13:1
Might be able to pick up some nice gains above the end of the torque curve,
was ignition done as well??