Adding turbo gives HUGE increase of RON

[jagermeister]

When adding a turbo with a preset setting to my standard 2.0 liter engine, RON increases with 10, thus unable to run.
How do I make turbo's work properly??

[Der Bayer]

- More fuel
- more aggressive Cam Profile
- lower Compression
- lower Ignition Timing
- less Boost

[jagermeister]

Yeah I know how to lower ron, but why is it increasing so madly with a turbo. How do I make economy engines with a turbo and make it run...like the 1.2 TSI from volkswagen...

[Kubboz]

Turbo compresses air.
Compression = heat
heat = more prone to knocking
also, intercooler = less heat

[jagermeister]

that explains it more. Thank you.

I also mentioned this is the turbo update string, sorry

[Daffyflyer]

Yup, you DO get huge Ron increases with a Turbo, and managing them is a complex business.

Key things are

- Good Fuel system, DI paticularly is excellent, also you'll need to run it richer than an N/A motor, no matter what you do.
- Effecient turbo setup, make sure the turbo is large enough for the boost/power you want to run.
- Good Intercooling.
- Low enough compression. Running above about 10:1 will start to get quite hard to do
- Low enough ignition timing.

[srb2nv]

Try a larger A/R ratio.

[tdonton13]

yes, all this is true, but the turbo release just came out today. and I've made both a cross-plane and flat-plane v8 with over 2000hp+ and 1400lb/ft+ with a "6.0:1" compression and "30+lb's of boost". i could take it to 2500hp and 2000hp, but the torque would destroy the crank shaft(billet steel).
what is a really strong material that could be made into a crankshaft?, maybe titanium.

[tdonton13]

specs of my engine.
8.0 litre DOHC 40 valve XP V8
2091hp@7800rpm
1439ft/lb@7500rpm
RON- 81.7
Fuel mixture- 11.8:1
Compression- 6.0:1
RPM limit- 7800
water to air huge inter cooler

that's all I'll tell you.

P.S. i've got it to about 2230hp, but the the torque is ruining the crankshaft so it was pointless to go any further.

[Kubboz]

Please, don't go offtopic. If you want to boast with your engine, post it on engine uploads forum.

[jagermeister]

I drive a XR3i from 1988 and my compression is 9,5:1
But the RS Turbo from the same engine has a compression of 8,2:1

Pretty much says it all. But I understand it now and it works fine. Thanks for the feedback guys

[tdonton13]

I thought someone would say that, but anyways I'm not boasting I'm proveing a point. That you can make apretty decent amount of power with very low compression. In my case 6.0:1. Just thought someone would be interested in the specs.

[zeussy]

The way to think about turbo's, is that they are increasing they are creating virtual capacity by increasing the volume of air at the bottom of the stroke. So per stroke instead of drawing in 1 litre of air, it gets 2-3 litres of air. This is why static compression ratio's have such an effect. As instead of compressing 1 litre of air down to 100ml with a 10:1 ratio, with 3 litres of air getting compressed into 100ml you are getting a 30:1 ratio! If your compression ratio starts low at 6:1, then you only get up to the dizzy heights of 18:1

[jagermeister]

Thank you

[RobtheFiend]

They really need to add E85 as fuel.
A friend is running a Honda V-2 1l engine with a turbo, it has 12.5:1 in comp and he runs 1.8 bar in boost (26.1PSI).
Before anyone starts yelling; "thats a motorcykel engine!". Remember that the engine has 500 cc per cylinder, same as a 2l L4.