change of cams?

change of cams?

Author
Discussion

davidd

Original Poster:

6,531 posts

291 months

Thursday 5th June 2003
quotequote all
Looks like I'm keeping the Cerbera and so now I'm looking at upgrades.

The car is an early 4.2 and by all accounts a pretty good one. As far as I'm aware the only mods are decat pipes so I thought that over time I'd do the following.

Wheels (cos I have been offered some) to 17" race or speedlines or whatever they were called.

Suspension to whatever I can afford at the time (Nitrons if poss and poly bushes)

Engine, looking at Joospeed intakes and cone filters, I also read at some point that Piper were making a cam for them. I have emailed piper but had no response can anyone shed any light on piper or other replacement cams?

Not interested in lights at the mo as I don't like the new ones enough to justify the spend.

Any comments on the cams and any other things I should think about?

D.

dannylt

1,906 posts

291 months

Thursday 5th June 2003
quotequote all
Not much point going as far as cams without knowing you've found someone to remap the engine too. I don't know of anyone who can do that yet.

Besides, suspension makes far more difference than extra power - I'd concentrate on that first.

danyn

davidd

Original Poster:

6,531 posts

291 months

Thursday 5th June 2003
quotequote all
Cheers Danny,

You are right the suspension will make the most difference. However the car is on early cams and so I suspect they will need changing at some point and the engine is in bits waiting for some parts so I thought if there was a cam kit with lots of good feedback then........you get my drift

Is no one doing engine remapping yet then? What can people like Joolz change with their software?

thanks

D.

BCA

8,651 posts

264 months

Thursday 5th June 2003
quotequote all
There are people out there working on the ECUs, but to my knowledge no one other than Cambell (C3RBA? on PH) has had a remap outside of TVR.

With cars that vary so much individually it would be stupid to think that the one map that TVR do works well for all the cars out there. Wouldnt suprise me if there were a few horses lurking about and a smoother power curve too.

dannylt

1,906 posts

291 months

Thursday 5th June 2003
quotequote all
Campbell has not had his car remapped. Apparently just an adjustable fuel regulator. The standard mapping is probably very conservative, probably where a lot of gains for the red rose cars come from.

With the standard dealer software, you can only reset the adaptive maps, you can change the base mapping.

The easiest way is probably still to put an Emerald on, I'm sure Joolz is only too happy for someone to be a guinea pig!

Danny

joospeed

4,473 posts

285 months

Thursday 5th June 2003
quotequote all
the emerald route is being done by someone I'm in contact with, hope to see some results soon but dave and karl are busy bees anyway.
There's still a feint chance on the MBE system becoming unlocked, but most interesting is someone I know who builds his own ECUs, ... big yay!
I contacted Piper about cams for the cerbie, but then i got into contact with the bloke who did the development cams for both the AJP8 and SP6 engines. You can have one of 5 alternative cam grinds for the AJP8, but at 1200 pounds a pair from blanks i thought better of it. the std cams are good for power to 6500 revs so little point in pushing that further up the rev range bearing in mind the fatally flawed inlet port design.
If Campbell had an adjustable regulator I hope they adjusted it down .. cerbies generally run too rich for max power believe it or not. On the rollers I use you can plot CO on the power graph, every time there's an area of rich running it loses torque, and there's plenty of rich running in the cerbera map.

boosted ls1

21,198 posts

267 months

Thursday 5th June 2003
quotequote all
You might find this interesting or you could look at a DTA or similar.

www.bgsoflex.com/megasquirt.html



joospeed

4,473 posts

285 months

Thursday 5th June 2003
quotequote all
looks great .. pitu it's fuel only at the mo .. would mean running an omex or similar in tandem.
DTA is great, but expensive since you pay for loads of stuff you don't actually need, and the name of course.
All I'm after is a simple no-frills ecu, there must be one somewhere, even the emerald is going to be traction control and launch control ready, so surely it'll go up in price also? A good simple quick set-up ecu for 200 quid is what the market needs, so why doesn't anyone do it? .. well maybe we will
Surely WEDG1E must have some ideas for knocking up a cheap ecu?

VYT

585 posts

269 months

Thursday 5th June 2003
quotequote all
Joolz

I don't know a lot about the input's / outputs required for an ECU but if you can let me know what you want I am sure I can get something together. I guess the sensors all produce a voltage that the processor has to read then the processor needs to set some control voltages based on some logic that you would like to be able to setup.

Depending on the I/O requirements it might be possible to take one of our existing control boards, certainly the macro language will allow you to alter the control strategy as you wish.

Let me know if there is any interest.

Bob

davidd

Original Poster:

6,531 posts

291 months

Friday 6th June 2003
quotequote all
So if the car cannot be tuned via the ecu does that mean I can buy the joospeed intake kit for my 4.2 bolt it straight on and magically get some extra BHP ?

If so what is the price not including fitting jools?

D.

AndyTather

73 posts

279 months

Friday 6th June 2003
quotequote all
I take it the password to unlock the MBE system is in the chip not the software ?? And where in the software can you enter the password ?

clarky5150

423 posts

275 months

Friday 6th June 2003
quotequote all
If i knew that answer, Clarkspeed would be giving Joospeed a run for his money!!! (how many cams are in this one then...Help me joolz!)

joospeed

4,473 posts

285 months

Saturday 7th June 2003
quotequote all

davidd said: So if the car cannot be tuned via the ecu does that mean I can buy the joospeed intake kit for my 4.2 bolt it straight on and magically get some extra BHP ?

If so what is the price not including fitting jools?

D.


that's about the size of it, one of the ways tvr make the 4.2 supposedly less powerful than the 4,5 is to put an inlet manifold on with a waisted section in, plus poor detail finishing around the first curved section. the least hp improvement i've had is 12bhp, the best 19bhp (that engine made the highest torque ever seen on a 4.2 cerbie i've tested. However, it's only 5-8 percent increase, you'l NEVER notice that out on the road, it's for people who like to talk hp figures and in the grand scheme of things it's a piss poor way of making your car go faster, which is why I haven't done any for about 12 months. A set of springs at 160 pounds is much better value for money!

Joolz .. telling it like it is.

joospeed

4,473 posts

285 months

Saturday 7th June 2003
quotequote all

VYT said: Joolz

I don't know a lot about the input's / outputs required for an ECU but if you can let me know what you want I am sure I can get something together. I guess the sensors all produce a voltage that the processor has to read then the processor needs to set some control voltages based on some logic that you would like to be able to setup.

Depending on the I/O requirements it might be possible to take one of our existing control boards, certainly the macro language will allow you to alter the control strategy as you wish.

Let me know if there is any interest.

Bob




er .. well this is why I'm no electronics guru .. haven't a clue what you're asking here!!
but: yes there's various sensors which send back to the ecu, primarily you have a crank trigger, a throttle position sensor, a coolant temp sensor and air temp sensor. you can also trim any fuelling with an air pressure sensor and exhaust oxygen sensors.
the ecu then needs to drive a pair of ignition coils and also two sets of four injectors on a time (pulse width) basis - injector duration... since the fuel pressure is fixed this is how it changes the fuelling.