Rally motor engine (ideas)

Hey forum i have making this (rally motor) and i will hear about you have some ideas i can add? i dont want any turbo charger in my motor i can show you other pictures of my settings if you ask


dont hope the engine is too big
Bore=101.4mm
Stroke=102.6mm

Settings (Bore and stroke)
Bore=101.4mm (EDITED LOOK BELOW)
Stroke=102.6mm (EDITED LOOK BELOW)
Crank=Billet Steel
Conrods=I Beam Titanium
Pistons=Hypereutectic Cast (EDITED LOOK BELOW)

Settings (Compression)

Head and Valves=Overhead Cam/4
Head Marerial=ALSI
Compression=6.9:1
Cam Profile=100 (EDITED LOOK BELOW)
VVT=VVT
VVL=VVL
VVL Profile=100

NONE turbo charger

Fuel System=Injection/Direct Injection
Configuration=Throttle Per Cylinder
Intake=Race
Fuel Type=Ultimate Unleaded
Fuel Mixture=12.4:1
Ignition Timing=86
RPM Limit=7500

Settings (Diameter)

Headers=Cast Log (EDITED LOOK BELOW)
Exhausts=single
Muffler Bypass=Bypass Valves
Exhause Diameter=6.00" (EDITED LOOK BELOW)
Catalytic Converter=High Flow Three-way
First Muffler=Reverse Flow
Second Muffler=Reverse Flow

Feel free to use my settings
I love the sound of this engine
Hope you enjoy btw sorry for bad english

EDIT:
Replaced the shitty cast log to a long tubular
Set the Cam Profile to 40
and used Lightweight Forged Pistons
I have done the engine smaller to fit in more cars (B 91.5 and S 79.0)
I have make the exhaust pipes smaller (4.25)

HP from 291 to 381

A few hints:

Replace the shitty cast log with long tubular or race headers, you can decrease the exhaust diameter then and will get a lot more power.

Set the Cam Profile to around 40 to make proper use of VVL.

Use Lightweight Forged Pistons if you use Titanium Conrods, else the money is pretty much wasted. You probably can raise the RPM limit a bit afterwards.

Hmm… cast log is not good to have for a performance engine unless it’s turbocharged.

Having your regular cam profile AND your VVL profile the exact same makes VVL pointless.

The exhaust pipes seem excessively large.

The bore/stroke seems excessively large.

The compression ratio seems excessively low.

I think you could make a much more balanced engine with much lower weight and displacement by changing around some settings.

Edit: That’s a 5.0 L straight-6 you’ve made there… that puts out less power than older build year 3.0L Turbo 6’s or 3.5L non-turbo V8’s that I’ve made. All of which are street, not race, engines. Have you worked through all the scenarios in the engine builder mode yet?

[quote=“VicVictory”]Hmm… cast log is not good to have for a performance engine unless it’s turbocharged.

Having your regular cam profile AND your VVL profile the exact same makes VVL pointless.

The exhaust pipes seem excessively large.

The bore/stroke seems excessively large.

The compression ratio seems excessively low.

I think you could make a much more balanced engine with much lower weight and displacement by changing around some settings.

Edit: That’s a 5.0 L straight-6 you’ve made there… that puts out less power than older build year 3.0L Turbo 6’s or 3.5L non-turbo V8’s that I’ve made. All of which are street, not race, engines. Have you worked through all the scenarios in the engine builder mode yet?[/quote]

Thanks i will look on it :slight_smile:

[quote=“Der Bayer”]A few hints:

Replace the shitty cast log with long tubular or race headers, you can decrease the exhaust diameter then and will get a lot more power.

Set the Cam Profile to around 40 to make proper use of VVL.

Use Lightweight Forged Pistons if you use Titanium Conrods, else the money is pretty much wasted. You probably can raise the RPM limit a bit afterwards.[/quote]

Many thanks for the hints!

Can you post the revised picture?

ofc

Raise the rev limited to a higher setting (8500?), as this is a rally motor, it has to provide the best powerband, and reliability is not as important.

The torque profile is rather odd for a competition engine, personally I’d drop the VVL if you’re only interested in performance in the powerband. I’d aim such that the peak torque happened at a bit over halfway up the revs and the peak power a few hundred RPM below the redline.

The engine seems to still have major optimization issues. Rather than nit pick it to death, I think it’s better to give an example for comparison. See what you think.

GSI 2.0L I6 Race 2014Rev0.lua (53.2 KB)

An even better comparison would be to a motor of the same size:

3.1L Rally I6 24VRev0.lua (53.1 KB)

Frede, there’s no point to economy in a rally motor, drop your air:fuel ratio to 11.8 for maximum power and response.

I thought inline 4’s were more common in rally cars(?)

Either way, interesting engine. You could probably increase the stroke a little to help with torque without hampering the redline (7500 is modest)