Murc or Tifosi engine for Donelots and Elves?

I have Donelot tyres and Elve fuel as my suppliers since the creation of my team... and Murc as my engine suppliers.
Now my engine contract is over, and i wonder, renew contract with Murc, or switch to Tifosi?
Which will work better with Dunlops/Elf?

Personally I use tifosi as are good on fuel and still has relitavely high power levels. Never reallly noticed the pace duren a race being diffferent between murk and tifosi unless your contnuosuly in competition like me and neds to run light fuel at the start of the stints to be fast and keep pos. Also I use beep fuels to make up for that tiny performance deposit between murk and tifosi and then run bridgerock tires but I would reccomend to stay with donelots I use both depending on the racce if it's somewhere like singapore I use donelots for cooler tires but somehwhere lke britian I use bridgerock as they're more competitive in lower tempratures:)
So just a repeat:
Tifosi Engine
Beeps Fuels
Bidgerock/Donelots tires

Wonder & Elves - Short Medium weight drivers.
Rednote & Elves - Medium height & weight drivers.
Toymotor & Elves - Tall Light drivers.
Murk & Elves - Light drivers.
Tifosi & Elves - Heavy weight drivers.
Cosurworthit & Elves - Tall heavy drivers.

Just making you think about your choices!! It's up to you what you want to use.

I would choose Goodweek as it's the winter time and temps are going to be cooler most of the time.

I have Cosurworthit, Elves & Goodweek with Medium height, light weight drivers & I do ok :D