stroking my m20 to 2.7i... day-by-day pics

[nando]

you can also keep things like A/C with SMT7.

[MrK]

SMT-7 is in and wired up, the cam has been returned to its optimum position, and the SMT was used to adjust the igntion timing to eliminate any traces of pinging.

The car is now literally a ROAD ROCKET compared to what it was stock! To say the least I'm impressed with the performance improvement. I'm now looking around for a WBo2 that I can borrow to fine-tune the fuel delivery.

I can comfortably say that my butt-dyno has registered a 30+ hp improvement over stock, but a real dyno test will be in order once I stick in a MAF.

Can't wait :)

Note: The SMT7 is beyond fantastic, and ridiculously easy to use, I'd recommend it to anyone who's modded their car more than the DME can comprehend.

[Sean]

SMT-7 is in and wired up, the cam has been returned to its optimum position, and the SMT was used to adjust the igntion timing to eliminate any traces of pinging.

The car is now literally a ROAD ROCKET compared to what it was stock! To say the least I'm impressed with the performance improvement. I'm now looking around for a WBo2 that I can borrow to fine-tune the fuel delivery.

I can comfortably say that my butt-dyno has registered a 30+ hp improvement over stock, but a real dyno test will be in order once I stick in a MAF.

Can't wait :)

Note: The SMT7 is beyond fantastic, and ridiculously easy to use, I'd recommend it to anyone who's modded their car more than the DME can comprehend.

So, what's the list of everything you did? What compression you running, etc?

You're making me want an SMT7! heh

[MrK]

So, what's the list of everything you did? What compression you running, etc?

You're making me want an SMT7! heh

Good question. A list of everything I did would be a great way to wrap up this thread. The following is what I did to make this engine go beyond stock:

1. eta crank to increase displacement to 2.7i
2. custom forged pistons, making compression about 10.7:1
3. Schrick 304/304 camshaft (not regrind)
4. high performance valve springs
5. Kent Cams adjustable cam gear
6. highbeam delete/cai (don't know how much difference this made)
7. Alpina long-tube headers
8. Bosch RW8LC spark plugs (colder plugs for raised comp)
9. 19 lbs/hr injectors
10. Replica Alpina C3 chip to raise redline to 6800rpm
11. SMT7 to adjust ignition and fueling

Soon to come is a MAF swap, but that's another story for another thread.
I'm also waiting for a guage for my Bavauto AFPR, but again I don't think this'll really tip the scales performance-wise.

If anyone notices that I've made some glaring omission, don't hesitate to comment.

I'm now saving up for ITBs, but it'll be a while before I have that kinda cash on-hand:(

[AdironRider]

Schweetness, now just get her on a dyno and see what some real tuning can do.

[s40boy]

I wanna see this! DYNO or ban...haha!

[MrK]

I wanna see this! DYNO or ban...haha!

Said the n00b with 53 posts (J/K) :D

I'll gladly call you on that statement.

Dyno run scheduled for Saturday 27th of May at 9:30am sharp :twisted:

I'll update once I have results...

I'll dyno again after installing the MAF to see what kind of gains can be expected from a highly-tuned engine changing from an AFM to a MAF.

[SchnellerVert]

I wanna see this! DYNO or ban...haha!

That's funny from a guy with a Volvo name.

[AdironRider]

Im eager to hear the results. The recent GRM with the writeup on a supercharged m42 has really perked my interest, but if this puts out substantial power, I just might have to go this route.

[MrK]

Dyno or Ban? I chose Dyno.

With all mods listed above, and m20 AFM. Will do a second run after the MAF is installed:



In short: I dynoed it, they DIDN'T have a WBO2 (insert expletive here)

The Bosch dyno measures wheel hp, and the then measures parasitic drivetrain losses, and comes up with crank hp.

Peak whp: 160
Peak hp: 191
Peak tq: 186 lbs ft

The dyno operator told me that my AFM is a severe bottleneck, so I'm looking forward to swapping in the MAF and seeing what difference it makes. For those of you who took a close look at the second pic, you'll notice a huge dip in torque at exactly 3000 rpm. Nothing I did with fueling or ignition would alleviate that dip. Thoughts?

[Sean]

Other than the choking - how's she running man?? How's that cam? That's really high duration!

I have an M30 AFM for mine, hopefully that will help some. ;)

Fun ride??? :D

I cannot wait to finish mine. *sigh*

[nando]

nice torque curve! (except for the dip of course).

160rwhp is a bit dissapointing though (with a 304 cam, youch!), hopefully ditching the AFM will pick that up a bit.

[digger]

Does the graph and data show wheel numbers or are they adjusted to crank numbers? Where does it show the whp and wtq numbers (all i see is the kw and Nm and don't know whether those are at the crank or wheels)?

[MrK]

OK responses:

Sean: The car runs real good, I still need a wideband to eliminate all the rich spots (of which there are plenty), and extract full power, but around town and on the highway it's just as practical as a stocker, i.e. smooth throttle response. The torque at 2000rpm is ridiculous, I made a friend (who owns an e30 M3) REAL jealous by showing him how I can do an easy donut on 2k rpm LOL. He needed 6k rpm to donut. The dip at 3000 is not much of an annoyance in real life, since driving normally keeps me under 3k, and driving hard keeps me over 3k :) So the 'cross-over lag' is only a problem like once in a blue moon when I decide to step on it before downshifting.

Nando: YES 160rwhp was VERY disappointing for me, considering the work I put into the engine, but several points need to be considered:
1. The temperature during the run was 31C (about 88F) = less hp
2. I'm running that severe intake restriction a.k.a. "m20 barn door"
3. My A/F tuning is likely off in places, due to the absence of a WBo2
4. My cam is not being put to full use. It's designed to 'sing' at around 7k+rpm, due to its extreme duration, something I was not told when I bought it. So in order to move it's 'peak' down the rpm range, and to stabilize the idle somewhat, I changed it's position slightly. Unfortunately this means it's not performing at its full potential.

Digger: The first graph shows both whp and crank hp. The solid line is wheel, and the dotted line is crank. Both are shown in KW, not hp. To convert, just multiply the KW number by about 1.3405. The second graph shows crank hp vs. crank torque (in NM). No wtq was shown. I can't be bothered to look up the conversion from NM to lbs ft, but it turned out that I peaked at 186 lbs ft.

More interestingly, I had about 157 lbs ft at only 2000rpm!!! (fun)

[nando]

the thing about strokers is you really should upgrade all parts of the system, fuel, intake, etc. the throttle body, AFM, intake manifold, and exhaust were all designed as one system for a 2.5l engine, they will work with a 2.8/2.9 but you'll never reach the potential of your motor. Once I have mine broken in, I will switch to a piggy back and ditch the afm, and eventually I'll do something about the TB and intake manifold.

I do think you would be better off (and likely make more power) with a slightly less agressive cam like a 288 or 292. you could build a head for 7k+ but that's pretty pointless on a 2v head IMO, and extremely expensive.

and yeah, the torque is nuts, it has more at 1,000 rpms than most M20s make peak! that's what I'd like most after HP, stump pulling power. going from a "stock" m20 with an auto to a stroker/5 speed is going to be a bit crazy :D