Trying to build a Honda F20c

[Der Bayer]

The exact RPM value, where the shift happens, depends mostly on how you set the cam profile for the lower RPM. It automatically shifts to the VVL profile as soon as this profile can produce more torque. So with a standard cam profile of 30 it will shift sooner to the VVL profile than with a standard cam profile of 40.
The other way around, like you said: For a given standard cam profile, more aggressive VVL profiles will be active at higher RPM, because they can't produce much torque at low RPM but at higher RPM.

Greets
Martin

edit: damn, too slow

[20cent]

I don't mean to threadjack, but I've been having problems trying to recreate a couple engines, myself. Was trying to do the 2ZZ-GE from the 7 gen Celica, and the S50B32 from the E36 M3. I had a lot of difficulty trying to get torque figures to match up in terms of RPM, because whenever I'd up the cams to get the horsepower right (at far too high an RPM), the torque peak would also rise.

Oh, also had this problem trying to recreate a Tipo F131 from a 360 Modena. Things seem biassed towards higher-RPM output, and I'm having issues even getting a flattish torque curve on the left side of the graph. Does this fall under 'nothing is set in stone'?

With this in mind! Would it be much to ask to have a way to set the VVL engagement point, in RPM?

Cheers!

I did not try the 2ZZ-GE, but I tried the S50B32... And I have the same problem (even with the M52B28 from the 328i E36, but for this one I think I can blame the intake manifold) : 361Nm at 4900rpm and 321hp at 8200rpm (sort of a mix between the S50B32 and the S54B32 in fact).
For the Tipo F131, don't forget it has some "special" bypass valves in the exhaust, I don't know if they are the same in the game.
Anyway, I think it is a better option to get the right torque at the right rpm at first, and then see what happens with the horsepowers

[frechett79]

I try to build Tipo F131 engine too. I find that the 3.5 and 3.6 version has 5 valves per cylinders.
I continue experimernts. I will post my work soon.

[Janekk]

I never before tried to recreate real engines but it was fun challenge. Especially Tipo F131 was pretty tricky to get 400HP at redline while having peak torque at 4750rpm.

F20C should be pretty accurate (but there is lots of room to play around with sliders to improve it), only 7 Nm off on peak torque, even VTEC kicks in at "around 6000 rpm".

In F131 peak torque is off by bit more but then it was hard enough to get that high end power with such early torque peak.

Both engines are 1999.

[statman]

There you go , here is my best shot:
Year:1999
Displacement: 1,997 cc (121.9 cu in)
Compression: 11.2:1
Bore: 87 mm (3.4 in)
Stroke: 84 mm (3.3 in)
Power: 250 PS @ 8,300rpm
Torque: 224Nm @ 7,400 rpm
Redline: 9000 rpm
Prod.Units:80.2
Material Cost:$987.01
Reliability:57.5
Economy:18.25%

F20C

F20C.jpg (292.63 KiB) Viewed 3127 times

[Maurice82]

Complete iron cast..? But the engine is aluminium?

[07CobaltGirl]

I'd like some help trying to build the Honda F20c. I'm not sure where I"m going wrong

Going from the wikipedia, we have
Displacement: 1,997 cc (121.9 cu in)
Compression: 11.7:1
Bore: 87 mm (3.4 in)
Stroke: 84 mm (3.3 in)
Rod Length: 153 mm
Rod/stroke ratio: 1.82
Power:
JDM 250 PS (183.88 kW) @ 8,300rpm & 22.2kgm (217.71 Nm) @ 7,500 rpm
USDM 240 HP @ 8,300 rpm; 153 ft lb, 207 Nm @ 7,500 rpm
Redline: 9000 rpm
VTEC: 6100 rpm

From this, I have the following settings:
Current Year 1999
Inline 4, Aluminium, 87mmx84mm, Forged Crank, Forged H-Beam, Forged Pistons
DOHC, 4valves, Al, 11.7:1, 61 on the lower cam, no VVT, VVL, and 100 on the upper cam
Multi EFI, Single TB, Performance Intake, Premium Unleaded, 12.3:1, 83, 9000
Long Headers, No Valve, 3", HF3-way, Reverse, Reverse

I'm only making 235hp.

Some quick observations I have are:

9000rpm Bottom end part is reducing lifespan. Is this right? No combination passes this in 1999
Fuel System. I haven't been able to get any engine to have a fuel mixture richer than 12.3 with it saying I'm running rich. Is there any factors which can change this?
The F20c header exhaust goes to a 2.5" exhaust, which drops power down to 195hp in Automation

Just some feedback to maybe fix some calculations. If I've made any mistake in my setup that anyone sees, can you let me know

I came up with two engines which are pretty close to the Wikipedia specs you listed. HP is occuring 300RPM high while TQ is coming 600RPM low and a few Ft-Lbs high. The attached engine is the cheaper of the two, but at a huge sacrifice in reliability at a mere 42.6. By making the changes below you can achieve a much higher reliability but with a sacrifice of a huge increase in cost/production units. It should also be pointed out the efficiency of these engines is garbage, or at least mine is.

F20CRev2.lua

(51.82 KiB) Downloaded 205 times

This version uses high end components in the form of Titanium rods and Lightweight Forged pistons:


This version uses lower end components in the form of I-Beam Steel rods Forged pistons:


These specs are the same on both engines:


Hopefully you'll find this helpful?

[Dragawn]

Whelp, here's my attempt, I had to play quite a bit with the "techpool" though, tried to give it that real V-tec "kick" from the dyno chart I found
https://fbcdn-sphotos-d-a.akamaihd.net/hphotos-ak-snc7/298474_10150341120854190_2001978800_n.jpg

anyways, here's the result:


runs 11.7:1 compression like the real thing, torque might be a bit off, and it was tough to get that sudden torque bump.