How much quicker - SR4 vs R400?

[chiz]

Has anyone any idea how much quicker around Oulton Park (full circuit) a Radical SR4 with 1200cc 190bhp Kawasaki engine would be over a road legal R400 on slicks and aeroscreen? i.e. not the R400 race car. We are talking the same driver here with the same ability.

I know we can't be exact, but are we talking 2 seconds or 10 seconds here?

I'm lapping Oulton Park in about 1:50 (88.1 average MPH) on used tyres (reckon a second quicker on new slicks). I have a road ECU, not sure if a track ECU would make a difference. Road legal R400 with aeroscreen.

I don't have any Radical SR4 lap times for the full Circuit of Oulton. They were racing at Oulton last weekend, but were using the shorter Island circuit which is 2.2 miles.

The fastest lap time in qualifying was 1:27.053, average speed of 92.05 mph.
Slowest was 6.5 seconds off (85.70 mph).

As you can probably tell I am thinking of racing a Radical SR4 in the Biduro Championship.

What do you think?

[dannylt]

I find it hard to believe new slicks would only be a second faster than used road tyres, even if by road tyres you mean ACB10's or whatever. Just based on my experience of course!

[Paul T]

Radical web site contains fastest lap times for Oulton, you can use the Clubsport times as a comparison, (close to SR4 times), Fosters 102.306 & Island 127.27.

The SR4 will always be a fair bit quicker than your R400, more downforce, mechanical grip etc, etc.

[Paul T]

Just looked at your question & my reply again and realized I've not helped much!

I race a Radical clubsport and race against Caterham R400 & R500 when in Semsec & 750MC races, the Radical is usually about 2 to 5 seconds faster depending on type & legth of curcuit.

Hope this helps.