just watched a vid on rally spec engine, how do they get 500nm of torque with only 300 ponies from the engine, with them stats would that not be a prefered option than masses of ponies????????

 

They have an air restrictor that limits total output, this doesnt effect midrange torque though which doesnt need as much airflow.

 

so what engine spec would they run as in comp ratio and turbo???

 

High comp 11 - 12:1 and bespoke IHI or garret turbo's....

 

is there anyone who builds these type engines and whta management they on, i can see an l8 with lag and water injection there

 

I have one sat in my car....well a YB anyway...and they are generally on pectel or subsequently pi management.....

Tommy (Field), Julian Godfrey, Harvey Gibbs could all spec and build a capable rally engine....you would not want one in a road though as the fuel we run them on is £2.30 ish a litre.....

The design of rally engines has been developed for many reasons and none really relate to the spec you would want in a road car engine....apart from perhaps throttle response....

 

(please anyone correct me if im wrong)

like chip said they run a restrictor which limits top end power, but to get such massive mid range torque they run a massive boost spike which then tails off at higher rpm due to said restrictor. also the higher compression isnt such an issue as it would be on a road car due to the fact it doesnt rev very high. thats the way i understood it works anyway?


id love a go in a proper rally car, must feel sooo fooking quick!

 

so it only really works at high rpm then, and stu i have been in an rs200 tarmac and a works esc cos and they sre f**kin good mate

 

no they are mid range beasts,, you wouldnt want one of these on the road

remember that they also have short diff ratios, to keep these engines at peak

 

I used to have a Group A Nissan GTIR Pulsar wich I bought of a mate who used to rally it.
I bought it purely as a toy for the road and I can tell you that it's useless on the road

Throttleresponse is amazing and the way it goes through the gears is insane BUT it's a lot of work as you're constantly shifting up and down the box.
Fucking amazing booting it out of a corner on slicks though

Best rallycar I've been in has to be a Group B Mazda RX7, body almost entirely out of plastic and a 13.000 rpm revlimit
The noise it made was insane and so was it's driver