S6 4.3 v 4.5

Author
Discussion

Buzz Billsberry

Original Poster:

1,306 posts

231 months

Sunday 19th August 2012
quotequote all
What’s the benefit of the 4.5 over 4.3? a part from the obvious! The torque and power figures are not a massive difference. So what’s the benefit of spending another 2-3k? is it really worth it?? I've not seen any torque curve on either engine. I assume that the torque curve is more uniformed across the rev range on the 4.5?

What’s the difference between the two in torque @ tick over?

I'm not that interested in bhp... that’s just all about a p*ssing contest. For me torque is king. It’s the stuff that gets it going...

Is there anyone out there who has driven both derivatives??

Buzz


Edited by Buzz Billsberry on Sunday 19th August 11:42

Hollowpockets

5,908 posts

216 months

Sunday 19th August 2012
quotequote all
big torque makes the big power so err... dont bother with the upgrade wink

Its not about numbers, if your driving on track peak BHP is important as you will find more often than not be high up the revs past where the torque curve is at peak.

Also torque is what breaks things, so gearbox/clutch/diff etc will suffer more and you need to decide if its worth it on the road.


DonkeyApple

55,180 posts

169 months

Sunday 19th August 2012
quotequote all
It's like 34DD v 36D.

The latter will impress more when talking down the pub but in terms of useage only a professional motor boater could discern a true difference. biggrin

Hollowpockets

5,908 posts

216 months

Sunday 19th August 2012
quotequote all
DonkeyApple said:
It's like 34DD v 36D.

The latter will impress more when talking down the pub but in terms of useage only a professional motor boater could discern a true difference. biggrin
Nice one, where did you steal that from? smile

DonkeyApple

55,180 posts

169 months

Sunday 19th August 2012
quotequote all
Hollowpockets said:
Nice one, where did you steal that from? smile
I have reason to believe its all my own work.

Englishman

2,219 posts

210 months

Sunday 19th August 2012
quotequote all
Try both and see if you can tell the difference? wink

Hollowpockets

5,908 posts

216 months

Sunday 19th August 2012
quotequote all
Excellent, pictures to go with this motorboating?

Was there ever a comparison made between the 4.3/4.5 and the RG FFF, i understand that specs can vary and some 4.3's are up power wise with 4.5's but just in general, the power outputs of a typical one of each?

Also why are the FFF engines only available as a 4L? surely RG could provide or source a crank/rod/piston set up can be put in the FFF engine to give the bigger displacement?

DonkeyApple

55,180 posts

169 months

Sunday 19th August 2012
quotequote all
Hollowpockets said:
Excellent, pictures to go with this motorboating?

Was there ever a comparison made between the 4.3/4.5 and the RG FFF, i understand that specs can vary and some 4.3's are up power wise with 4.5's but just in general, the power outputs of a typical one of each?

Also why are the FFF engines only available as a 4L? surely RG could provide or source a crank/rod/piston set up can be put in the FFF engine to give the bigger displacement?
Sadly no pictures. Even more sadly, the opportunity to advance any skill using different mediums has come to an end. smile

RG have looked at displacements but the chap who designed the head was of the view that it wouldn't give stellar gains. There was also the view that as the head develops the power at high revs that stroking may actually give no results and increasing the bore could increase heat issues.

An I right that Jason's engines are giving the best results for the rebuilds with increased cc?

Either way those three firms seem to be offering products with different characters so a nice range of choice.

Don1 had a run on track against a 4.3 or 4.5 and was of the view that they had more grunt low down but gave it back at the top. This seems to fit the general consensus and that more people will prefer this option for road use.

Hollowpockets

5,908 posts

216 months

Sunday 19th August 2012
quotequote all
Think Jasons 4.3 builds are giving more but cost £3k+ more for the build, plus some other bits.

What is the price of a FFF re-build? its not on the website and i dont want to call RG to bother them again at the mo.




DonkeyApple

55,180 posts

169 months

Sunday 19th August 2012
quotequote all
Hollowpockets said:
Think Jasons 4.3 builds are giving more but cost £3k+ more for the build, plus some other bits.

What is the price of a FFF re-build? its not on the website and i dont want to call RG to bother them again at the mo.
Not sure to be honest. All of my stuff was a single figure based on the total reconditioning of the Typhon.

Don1 has a thread where he talks about the costs.

I think the RG package is always going to be more expensive as to get the best results it would be wise to also buy the replacement management system and some other bits. Then there is the VcT in the works.

Have you had a chance to drive the various options yet?

I found them chalk and cheese so making a choice as to which you prefer is quite easy. I think costs are pretty similar.

Don1

15,939 posts

208 months

Sunday 19th August 2012
quotequote all
The costs are similar, but RG are very good a selling extra bits. Budget £5k for the FFF head, £2k for Syvecs, then exhaust, air box etc.

Final bill for me (inc VAT) was £15k. But that means 443bhp and 360 lb/ft. And it revs so quickly....

That track day was me running the car in and shaking it down. I was under 420bhp, and 4 year old tyres. I would also say that I'm not the fastest on track - I'm well aware of my limitations.

With how the car feels now compared to how it did, I would say the car would loose a few metres if I'd launch under 3k rpm. But then it would catch quickly and just walk away. It is that fast.

Anything you'd like to know, please ask. I've said from the beginning I'll be transparent about it all.

Getsis

1,537 posts

216 months

Sunday 19th August 2012
quotequote all
I've driven both:- results below

4.3 no need for traction control
4.5 get it or die

Thats the difference :-)

My 4.5 map
Red 95 octane
Blue 98 octane



What I can say is that a 4.3 on 98 octane will be very close to the red line

RedSpike66

2,336 posts

212 months

Sunday 19th August 2012
quotequote all
300lbs/ft from 2000 rpm, and 370lbs/ft peak - presume it'll rev quite quickly considering that whatever people say about the 'stroker' engine, plus CR box and 3.73 diff.... and very sticky tyres required no doubt hehe

Interestingly, Don's is 50bhp more but similar torque ??

Edited by RedSpike66 on Sunday 19th August 16:23

330p4

668 posts

230 months

Sunday 19th August 2012
quotequote all
Depends whether the above is wheel bhp
Ian

spitfire4v8

3,991 posts

181 months

Sunday 19th August 2012
quotequote all
its flywheel. racing green are defo winning the bhp race at the moment.

Hollowpockets

5,908 posts

216 months

Sunday 19th August 2012
quotequote all
Surprised 95 vs 98 ron makes such a big difference, Never seen that before!

Getsis

1,537 posts

216 months

Monday 20th August 2012
quotequote all
Hollowpockets said:
Surprised 95 vs 98 ron makes such a big difference, Never seen that before!
The big difference is because the ECU (Syvecs) retards the engine on 95 to prevent pinking.

GTrr

1,627 posts

282 months

Monday 20th August 2012
quotequote all
spitfire4v8 said:
its flywheel. racing green are defo winning the bhp race at the moment.
surely a 4.5 is 395 bhp at the wheels, about 450 at the fly

jcpgasoline

278 posts

214 months

Monday 20th August 2012
quotequote all
GTrr said:
surely a 4.5 is 395 bhp at the wheels, about 450 at the fly
Transmission losses are about 15% (some would say 20%). So 395 bhp is 85% of flywheel bhp.

=> 395 / 0.85 = 464.7 bhp or 465 bhp approx.

jcpgasoline

278 posts

214 months

Monday 20th August 2012
quotequote all
Getsis said:
I've driven both:- results below

4.3 no need for traction control
4.5 get it or die

Thats the difference :-)

My 4.5 map
Red 95 octane
Blue 98 octane



What I can say is that a 4.3 on 98 octane will be very close to the red line
My traction control solution for my 4.5 Tuscan was bigger rear tyres (265 R18 Toyo R888) with a close ratio gearbox (1st, 2nd & 3rd all taller gears) coupled to the 3.73 diff. It works really well most of the time, just not in winter. Winter performance tyres may be the cold weather solution.