Anyone upgraded a standard 4.0 to "S" spec?

[robsco]

Hi all.

As above, looking for some opinions on this? Will I notice an appreciable difference?

Thanks in advance.

[Hollowpockets]

Went from a 3.6 to 4S when my head went on the t350, not noticeably faster.

[DAVEY DEE]

Isn't the s just different cams? Or was that the red rose?

[robsco]

The cams are the same, the bottom end would be stripped to deck the block to increase compression. Also bigger injectors and a chip in the ECU, presumably for the alterations in fuelling etc.

[dpd3047]

Change Centre line Angles to 113.5 inlet and 107.5 Exhaust thats as Red Rose/S/And Sagaris remove head use use .045 thou thick gasket to raise compression to approx 11.5 this will give you about 12 to 15 bhp over standard output of 342 bhp get a remap, in my opinion you dont need injectors as the remap will take care of a wider band width for the extra fuel, decat will add about 5 to 8 bhp. Dave RND

[donski58]

Hollowpockets said:

Went from a 3.6 to 4S when my head went on the t350, not noticeably faster.

That surprises me as the 4.0 S is supposed to produce at least 30 more bhp than the standard 3.6. I am sure that Dave from RND will confirm the bhp quoted for the 2 engines.

I guess if it does not feel noticeably faster stick to the 3.6 and save some money!

[dpd3047]

A Standard 3.6 is 335 bhp @ 7000 the Red Rose/S/Sagaris
make 355 @6800 (see my above post)so its approx 20 bhp
even though there is capacity increase of 11% it does not equate 11% more power !! as for torque the 3.6 peaks at 5000 rpm and 4.0 peaks at 4500 rpm.

[robsco]

Thanks for the advice everyone. The top end is set to be rebuilt under warranty anyway, it seems silly not to pay towards stripping the bottom end and sorting that out at the same time. It's just a case as to whether to go to "S" while we're at it.

[DAVEY DEE]

Robsco it does make sense to go the whole hog while your messing with it.You'll prob regret not doing it if you don't.

[robsco]

My sentiments exactly Dave. How are you anyway, did you get your Cerbera rebuilt? I recall she was burning a fair bit of oil.