i was cruizing through DSM talk's advances section. and i know that stroker motors and the 2.4L swap are all the rage...but here is something new.

http://www.dsmtalk.com/forums/showthread.php?t=106361

discuss

I really don't see the point. I understand that going with a longer rod will put less pressure on the side of the cylinder wall, but you're losing displacement.

As my understanding goes, you'll lose tones of torque, and take longer to get into your power band. However, you'll probably have a wider power band, and stay in it longer.

I was playing in Desktop Dyno and compared the 2.4 vs the 2.0 and de-stroked the 2.0 to a 1.8l (I would have thrown the 2.2l in there, but I didn't know it's stroke or actual displacement). The 1.8 doesn't start to out-perform the 2.0 until 7500 rpm, and doesn't drop off quite as drastic. I compared with the crower3's, 11:1, 60mm TB, cams retarded 4*. It's max HP was never more than either of the other two.



I put boost to it and that 1.8l came alive. However, the 2.4l had as much as like 35hp more than the 1.8l earlier in the RPM range, and shit loads more torque:



Make your own assumptions, but I still think that displacement is key. You could gear the car completely differently to get up in your powerband quicker, but it's still got 40+ ft-lbs of torque less than the 2.4l all the way up to 4500 rpm.

**EDIT**
Fundamentally, isn't the 2.0L a de-stroked 2.4L? Same bore, but different stroke, but taller deck on the 2.4? Correct me if I'm wrong.

**EDIT 2**
If you used the 2.4 block and the 2.0 crank (if even possible, or machined to fit), then you'd need longer rods, which will improve the ratio and you'd probably be able to spin higher RPM's as well. Just a though, however.

This idea is about as useful as supercharging a 4cyl. IMO, why would you willingly trade torque for a little more high end horsepower? One would say " more rev's means higher top speed" but that’s not true unless it has the ability to push the car past the air/weight speed barriers. That and I would think this type of engine would be better suited to a drag racing engine backed by an Auto tranny (unless you're Takumi) and we all know how everyone feels about the ATX. That and I've never seen a transbrake for an A604 (Infint3, we need you). All in all this would make for a really fun albeit disappointing money pit of a project, so if you have the funds and patients, go for it and see what you can end up with, otherwise, stick with proven.

Originally posted by cougar694u
I really don't see the point. I understand that going with a longer rod will put less pressure on the side of the cylinder wall, but you're losing displacement. As my understanding goes, you'll lose tones of torque, and take longer to get into your power band. However, you'll probably have a wider power band, and stay in it longer. I was playing in Desktop Dyno and compared the 2.4 vs the 2.0 and de-stroked the 2.0 to a 1.8l (I would have thrown the 2.2l in there, but I didn't know it's stroke or actual displacement). The 1.8 doesn't start to out-perform the 2.0 until 7500 rpm, and doesn't drop off quite as drastic. I compared with the crower3's, 11:1, 60mm TB, cams retarded 4*. It's max HP was never more than either of the other two. I put boost to it and that 1.8l came alive. However, the 2.4l had as much as like 35hp more than the 1.8l earlier in the RPM range, and shit loads more torque: Make your own assumptions, but I still think that displacement is key. You could gear the car completely differently to get up in your powerband quicker, but it's still got 40+ ft-lbs of torque less than the 2.4l all the way up to 4500 rpm. **EDIT** Fundamentally, isn't the 2.0L a de-stroked 2.4L? Same bore, but different stroke, but taller deck on the 2.4? Correct me if I'm wrong. **EDIT 2** If you used the 2.4 block and the 2.0 crank (if even possible, or machined to fit), then you'd need longer rods, which will improve the ratio and you'd probably be able to spin higher RPM's as well. Just a though, however.

no way that would work, the journals on the crank are 100% bigger on a 2.4 compared to a 2.0

Originally posted by SILVERNT
no way that would work, the journals on the crank are 100% bigger on a 2.4 compared to a 2.0

420A = 50mm Journals
2.4L = 60mm Journals

I would never destroke a motor that already is light on torque. It's one thing to talk about de-stroking a V-8 that has torque to spare, and only low end power. You can keep good torque and increase engine redline by de-stroking it. But on a 4 cylinder engines that aren't exactly torque monsters all you are doing it taking your power band and moving it WAAAY up in the rpm range. I'd rather make the power at normal engine rpm, not 12,000.

Exile Racing Technologies
http://www.exileracing.com
Go that way, really fast, if something gets in your way... turn.

Interesting concept, but not exactly new. Here is a thread from this section, 2 years ago:

http://forums.2gnt.com/dcboard.php?az=show_topic&forum=32&topic_id=528&mesg_id=528&page=3

Corbin

'95 ESI-T
Now with more power and fewer leaks



Gimme fuel...Gimme fire...Gimme that which I desire

I have seen a guy in magazine that did this with an Audi 5 cyl.
The full build cost him alot of money, but he was running 45 psi,
900awhp, around 750ft/lb. If I can find the article I will post the specifics. Not a bad idea if starting with the 2.4 and alot of money.

The Audi engine started as a 2.3, and was destroked to a 2.1. The owner of the car did not reveal the internal specifications, not even what the rods were made of or how he achieved the de-stroke, whether it was longer rods, or any other means of de-stroking. Redline is set at 10,200 RPM. As I posted before 45 PSI, 900 HP, "Dynoing has been an issue, since it not possible to achieve reliable traction above 5800, and maximum power starts around 8000." And this is a street driven car, could almost be considered a daily driver. Sure you may have to rev the piss out of it to make any usable power, but you would have some serious bragging rights. I can scan the article and email it to anyone interested. It has most of the specifics on fuel system, drivetrain, exhaust, and intake set ups. Oh, BTW, the car reportedly cost $500,000 to build. Though carbon, and unobtanium were used quite liberally in the construction of the car, and he used an Audi IMSA racing 6 speed with custom ratios, so there is a lot of the cost right there, but the engine obviously cost mega$$$ to build.

$500,000??? FFFFFF that

$500,000? Sigh... Carrera...

Precisely, a very expensive endeavor to get an engine to sustain that kind of load. Although his golf had a hp:weight of like .40hp/lb. Still, is that kind of scratch worth it? Depends on who is building it.

Id rather put a rupper light High HP Indy engine into a say..lotus? or just buy the damn indy car...