Improving engine performance and bhp

[marcus1970]

What sort of tweeks can be done to the standard cerbera 4.5 to give it that extra edge? I hear that Austec know a thing or two! What is the top speed that anyone has achieved on our motorways in a 4.5?

[SXS]

You dont want me to start

Best people to talk to are, Joospeed, get your next service done with him, and he'll up the stakes in all the right areas with the budget mods which *do* make a difference... and then probably go down to Austec and get a rolling road remap done - but I think thats a waste of money personally - the advantages are minimal, especially after a good service and tune up... the other thing you can do, is be the first to use Boosted LS1's engine upgrade offer... between 8-15k depending on bhp requirements...

[pies]

Austec have now STARTED remapping the cerbie

[Mark Adams]

With all due respect SXS, I don't think the "waste of money" comment about the Austec remapping service is particularly helpful. Personally I would only comment on the value of things I have tested and experienced.

I am also sure that the gentleman who picked up 53BHP after having his one seen to at Austec a couple of weeks ago may possibly disagree with your assumptions. Note some of the gains came from cleaning the injectors, on a car that was otherwise well set up.

There is a great tendency to concentrate on the headline power figures, and these are only a very small part of the picture. It is not just the power though, it's drivability which is hard to measure without driving it. Also there are major gains in low and mid-range torque to be had.

Don't mean to offend - I am sure that was just an oversight on the part of someone who normally does do their homework. I have been entertained by your project, and continue to follow it with interest. Keep up the good work!

[Mark Adams]

One other thing - I don't think the gains made on a sample of two or three cars implies that this is valid for all of them! The info about the last car done does not necessarily apply to them all. The truth will come out with time...

[joospeed]

Good post Mark.

There;s now 8 cars up and running with the Emerald ECU and without exception they've shown both power gains and better driveability, pretty much as you would expect

I'm down at Emerald later this month with a std 4.5 (for once, every other car I've sent had been modified to some extent, will be nice to get a baseline 4.5 figure) .. so watch on my website for updates there.

Also, on my website is a link to interesting rolling road graphs I've done .. there's a std 4.2 cerbie on there early spec engine and ecu chip so this is the *minimum* you are likely to see from remapping, as these were the best power producing cerbies the factory did without going for RR upgrades)

HTH

Joo

[stas]

You know some thing guys , most of us on this forum,
would have had expirienced , powerful cars prior
to the aqusition of our Cerbs. I dare say that
most of us have some technical/mechanical Knowledge
too.
How many people here would say that you can
tell the diffrence say, between 300 to 350bhp
or say 350-400bhp ?
I personaly do not believe that you can
really start to notice a Marked diffrence until
these figures are considrebly increased.(SXS)
The point I'm trying to make here is that,by
keeping your car well tuned, (we obviously have
a wealth of Knowledgable people here on this forum)
we have one of the most Beautiful/outragiously
quick cars ever to hit the Public roads .
Enjoy guys/Gals .......and don't worry too much
about BHP its all subjective.
Stas( how many people still grin?

[SXS]

Valid points, but my post about waste of money, was more along the lines of, the cost compared to the return which is negligible...
Thats why I mentioned a good service and tune-up is worth more than the latter...

Anyway, I would love to see a dyno chart from a car which has been at Austec for the remap, and then a dyno chart from another reputable rolling road owner for comparison (without telling them about your existing chart)...

Being devils adovocate here really...

[SXS]

PS. with all due respect Mark, if you notice in my original post, I did say 'personally' - which would indicate I wouldnt bother... and not my general for/against opinion on the whole subjective remapping job... otherwise I wouldnt have mentioned it...

If it makes a difference of 53bhp on someones car, then that car must have been in a real bad state to start off with... in general, from what I understand, your torque will become smoother and bhp might edge a little forward, if your car was already well tuned... and in most scenarios - this would be considered a waste of money, I can think of a number of areas to spend that money to get a little more 'umph'....

[joospeed]

stas said:

You know some thing guys , most of us on this forum, would have had expirienced , powerful cars prior to the aqusition of our Cerbs. I dare say that most of us have some technical/mechanical Knowledge too. How many people here would say that you can tell the diffrence say, between 300 to 350bhp or say 350-400bhp ? I personaly do not believe that you can really start to notice a Marked diffrence until these figures are considrebly increased.(SXS) The point I'm trying to make here is that,by keeping your car well tuned, (we obviously have a wealth of Knowledgable people here on this forum) we have one of the most Beautiful/outragiously quick cars ever to hit the Public roads . Enjoy guys/Gals .......and don't worry too much about BHP its all subjective. Stas( how many people still grin?

Not true, if you're even remotely in tune with your car you can feel the difference.
When Dannylt had his red rose conversion done the difference was staggering, even flicking the switch from 97 to 95 octane gives a power change (a loss of course going that way) you can feel, and this is about 25/30bhp on his car (398bhp base figure).
The difference between 300 and 350 bhp is an even bigger % change and if you can't feel that then you shouldn't really be driving a performance car imo!

But more than the base performance gains is the better response to the throttle (especially on the fluffy 4.5 models). It's one of the few things you can do where you get your cake and eat it .. engine performance isn't any where near as good as suspension / driver training and tyres for performance gains, but if it's just straightline thrills you're after then you can't beat upping those torque/HP figures

[easto]

My std. 4.5 is running a bit gruff i think...so i am hoping to let someone have a neb round it to see if anything is a miss. Then it will be at john nobles for a rolling road (to satisfy my curiosity mainly!) not sure if they can produce any gains, peak power or low down torgue, maybe a smoother uptake in power.....god knows. But they do have an accurate RR

But hopefully will have another benchmark 4.5 figure....

[joospeed]

Nobles do all my power runs so we can compare to every other car I've run on there

best of luck ..

[easto]

Well saying that joolz....you were the man i was going to call anyway...i know how normally you are very busy though!

[SXS]

joospeed said:

stas said: ... How many people here would say that you can tell the diffrence say, between 300 to 350bhp or say 350-400bhp ? I personaly do not believe that you can really start to notice a Marked diffrence until these figures are considrebly increased. Not true, if you're even remotely in tune with your car you can feel the difference. .... and if you can't feel that then you shouldn't really be driving a performance car imo!

Joo, easy there, stas is making a valid point, I see where he's coming from... take this for instance, how many people out there regularely will be driving their beast at 6500rpm+? in general, low down torque is something you do notice, but overall BHP is really not noticeable until it hits you, and in most cases people just dont take their car that high on the rev meter, i've personally come across many who change their gears as soon as they hit the 4000rpm mark...

In my 3000GT, I put my foot all the way down and drop the clutch, and off I go, like a rocket, I get 300+bhp at around 3000rpm! and I really feel it! but of course, the weight of her lets her down, but in comparison, the cerbs dont produce anywhere near their top power until up in the rev-range, which I'm sure if someone was driving at on a regular basis - their car would spend more time on the back of a flatbed than on the road....
She revs quick and very loud - and not everyone can handle the 'umph' in first and second at the top end of the rev range, taking the weight of the car into account and typical tyre/suspension setups... boy do I wish she had four wheel drive...

[joospeed]

Lol, I wasn't being hard on him tho Ash! .. what seems to be confusing you maybe is that altho many people talk of peak power figures, many mods make a power increase over the whole range, remapping the cerbie and the red rose upgrade both do this from the very lowest revs to the highest, it can only make the car faster, and it's instantly noticeable to anyone. I don't know how to make it any clearer ..

[GreenV8S]

Mark Adams worked his magic on my 4.0 RV8 when it was standard. The peak power and torque only improved slightly, but the mid-range torque and particularly throttle response was transformed. Subsequently I had a lot more work done on the induction system including V8D stage IV heads/cam and ACT goodies. Peak power only increased by about 15%, but it transformed the engine from a stump puller to a little screamer that seemed to pull better and better the harder you revved it. It was an absolute joy to drive on the track and the difference in the engine characteristics was very noticeable. Of course after six months I got used to the extra power and only really noticed it when I was in other 4.0 cars that seemed to run out of puff at 5000 rpm. Subsequently I went for a capacity increase to 4.6, again with the worked induction. This has given me another 15% power which was nice but also shed loads more torque everywhere which is *really* nice. I wouldn't say I've got used to it, but I do recognise now that the car is capable of handling significantly more power. Whic is quite interesting, because back when I had an S2 I would have guessed that the chassis was good for maybe 200 bhp with care; I'm looking to double that.

I'll defer to Joolz' view on the tuning potential of the Cerbie engines, but my guess is that there are at least small improvements in torque and throttle response to be had, and if so I think they would be just as noticeable on a Cerbie as they were on mine.

[SXS]

I know what you mean joo, wasnt having a go bud... lets say, we look at a chart of a remapped cerbie, the power gradually starts to pick up higher, and once at the other end of the chart, you see the big jump of HP, but this is a gradual rise above the norm...
I think everyone feels the difference, but unless its mega-torque and mega-HP, it means nothing to the average joe-bloggs who uses his ride for a saturday pose... but translated into strip/track times - YES, big difference!...

Theres two main groups of fantasy supercar owners - ones for the pose/thrill/enjoyment, and ones for the track/drag/sprints.....

we know where we fit, but most owners here will be in the first group... any most of what I've been saying in this post is relative...

PS. I'm mega pissed off, I was getting this nice thing made for the car as part of the project, and just realised it wont fit!!!! ARRRGGGGGRRR!!!!!!

[SXS]

GreenV8S said:

I'll defer to Joolz' view on the tuning potential of the Cerbie engines, but my guess is that there are at least small improvements in torque and throttle response to be had, and if so I think they would be just as noticeable on a Cerbie as they were on mine.

Definately, but not necessarily more power across the rev range... and most charts I've come across so far, the ones online, ones flashed here and there across the pistonheads forums and other forums, all have one variable factor which is one hell of a misleading thing - drivetrain loss! Some charts have had DT-Losses put at 50bhp+!!! What????? I'm not very optimistic about most things until I see hard facts, and what I've seen pushes me to at least in one way or another advise those who will listen against jobs which are generally not really worth it as far as what they expect to see and it isnt delivered...
IMO > its far cheaper to add an extra 1k here and there and get some *REAL* difference making mods done... than waste time and money sorting out brake noises and decatting and light cosmetic mods and rolling road time etc... these firms out there offering all these wonderful services just pull these poor buggers in and get them to part with their cash for f'all... I'm sorry, but if we are to give advise to others, then we should at least give the negative side as well as the positive side with all known accounts of data, so that the respective poor bugger can make his/her mind up more intelligently...

[joospeed]

ok then I'll agree to this bit . I'll keep doing stuff to make the cars faster, whether or not the owner is sufficiently in tune with his car to notice is however another thing

[SXS]

joospeed said:

ok then I'll agree to this bit . I'll keep doing stuff to make the cars faster, whether or not the owner is sufficiently in tune with his car to notice is however another thing

I've always recommended your mods and services Joo, because you're just one of the very few people out there who will be honest about the facts....
But many other firms out there are just not as straight-up as you... forget the dealers altogether - they're money pinching, two-faced, stiff upperlipped conmen.... (apart from a few individuals who work for some dealers who will actually advise you well)....

And I still believe your airbox mod makes a BIG difference in overall power curve smoothness... and that is a cheap as chips mod.... no need for rolling road time to prove there is a difference - you feel it instantly when you start shifting....