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Albatross

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Re: Exhaust configurations
« Reply #30 on: 14 December 2008, 10:07:42 »

I used to have a 2.6 straight 6 Carlton which was given a chip and new head by Courtenay years ago.

I did ring them a few months back, but I must admit I was less impressed than I was previously. They did seem a bit reluctant. They said they could do more with a 3.0 than with a DBW 3.2. The main problem they said was the fact that there was less demand and therefore not enough money in investing in the research to create a remap for that engine just yet.

Having said that I do note that they now offer the following:

Quote
3.2 V6 into Vectra B
3.2 V6 Vectra B
We now offer the 3.2 V6 engine transplant into 2.5 V6 Vectra B from Ł4750. At the time of transplant we can also offer head re-working, sports camshafts, lightweight flywheel or any of our other tuning components to compliment the conversion.

I appreciate that the flywheel is useless unless I was to go to a manual conversion (which is unlikely), but the head and cam work looks interesting.

I know that many (TB) slag them off ferociously as being expensive tat, maybe that is right nowadays, but I didn't think that myself when I used them in 1995.
« Last Edit: 14 December 2008, 10:11:28 by Albatross »
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Kevin Wood

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Re: Exhaust configurations
« Reply #31 on: 14 December 2008, 10:53:07 »

Quote
an interesting read, esp the bit about emissions. All manufacturers suffer with this compromise, as im sure you know, and some very nice improvements can be had by returning the motor to how Mr Vx intended, not some eco Nazi tosspot behind a desk.

http://www.courtenaysport.co.uk/index.php?act=viewDoc&docId=21

A few pearls of wisdom amongst a load of speak that is designed to appeal to boy racers, IMHO.

You already have a very light flywheel, of course. It's just bolted to a very heavy torque converter. ::)

Exhaust / induction information is based on the FWD setup which, I imagine, has a different set of compromises to the RWD.

Water wetter, plugs, leads, cooler thermostats, air filters, etc. are a distraction. IMHO

You won't need a 4 bar pressure regulator unless you're running out of flow on the current injectors.

There's no such thing as a cam that improves torque and power unless the original cam is ridiculously mild. It will sacrifice low RPM torque for high RPM torque and hence give a higher power output, but by inserting a hole in the torque curve where the engine probably spends most of its' time on the road, especially with an autobox.

I think if I were you, wanting to improve the car but not go silly, these are the things I would try. This is based purely on what I perceive to be the weaknesses in the current engine rather than cold hard facts based on real experimentation:

Make sure the engine is running perfectly to start with.

Take off the induction system and make sure the inlet tract is smooth with no "steps" from plenum to cylinder head. Leave the internal surfaces smooth but not polished.

Fit some tubular exhaust manifolds.

Experiment with ditching the pre-cats. Perhaps a pair of 3.0 cats. If that doesn't help, perhaps weld some "sports cats" in instead and try them.

Maybe have a go at some mild porting of the heads and make sure the top end is working well (lap the valves in, etc.).

Once I've finished, find someone who can map the 3.2. IIRC, SP_3.2s car has been remapped so someone has the capability. This should include tuning on a rolling road, developing a map specific to the mods I have made not just charging 250 quid to lob in a new map.

Kevin
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Albatross

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Re: Exhaust configurations
« Reply #32 on: 14 December 2008, 18:37:07 »

Quote
Quote
an interesting read, esp the bit about emissions. All manufacturers suffer with this compromise, as im sure you know, and some very nice improvements can be had by returning the motor to how Mr Vx intended, not some eco Nazi tosspot behind a desk.

http://www.courtenaysport.co.uk/index.php?act=viewDoc&docId=21

...I think if I were you, wanting to improve the car but not go silly, these are the things I would try. This is based purely on what I perceive to be the weaknesses in the current engine rather than cold hard facts based on real experimentation:

    [1]Make sure the engine is running perfectly to start with.

    [2]Take off the induction system and make sure the inlet tract is smooth with no "steps" from plenum to cylinder head. Leave the internal surfaces smooth but not polished.

    [3]Fit some tubular exhaust manifolds.

    [4]Experiment with ditching the pre-cats. Perhaps a pair of 3.0 cats. If that doesn't help, perhaps weld some "sports cats" in instead and try them.

    [5]Maybe have a go at some mild porting of the heads and make sure the top end is working well (lap the valves in, etc.).

    [6]Once I've finished, find someone who can map the 3.2. IIRC, SP_3.2s car has been remapped so someone has the capability. This should include tuning on a rolling road, developing a map specific to the mods I have made not just charging 250 quid to lob in a new map.

Thanks Kevin:

:y I'm fine with points 3 & 4.

:exclamation Number 6 is pretty straightforward and I have sent a PM to Steve. I know to wait until the rest is done.

:question I'm fairly OK about point 1 (would a reassuring live reading from a Tech2 be enough?)

:question Any guidance or further detail about how to approach number 2 (this looks as though it may be within my capabilities)?

:question I guess that point 5 is where a place like Courtenay would come in; what do you think?
« Last Edit: 14 December 2008, 18:39:18 by Albatross »
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Albatross

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Plan of attack
« Reply #33 on: 14 December 2008, 22:30:29 »

OK, Having dug around a bit on ABS, chatted with Steve (SP_3.2) and considered Kevin's wise words, I think I have a plan...

Pre-test

Try the 3.0 mid sections which are free as a trial to remove the pre-cats.



Step 1:

Get these guys to make me a set of manifolds and sports cat (200 cell) mid sections. They have a proof of concept set in the making for an ABS member as we speak.

http://www.powerspeed.co.uk/



Step 2:

Then after searching around go to someone like Courtenay (or Courtenay themselves) for the head and inlet work. I'll get them to fit the manifolds whilst the heads are out.

http://www.courtenaysport.co.uk/index.php?act=viewDoc&docId=21



Step 3:

Final stage will be a quick trip to these guys to get the remapping done on a rolling road.

http://www.chippeduk.com/contact.php


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feeutfo

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Re: Exhaust configurations
« Reply #34 on: 14 December 2008, 22:33:37 »

i was thinking more along the lines of asking them, or any other company with the knowledge, about the effect of various lengths of header pipe and the likely state of the power curve once the desired length was fitted...?

Ie the effects of cylinder scavenging (works better the higher the revs, afaik, and hence a peaky tune?)
with header pipes. Or a flat torque curve with the current set up(plumun manifold) i am assumeing the plenum manifold has this effect on the tune?

 Personally i'd leave it be, but very interested in the results of this. Fuel prices are coming down. :-)
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Kevin Wood

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Re: Exhaust configurations
« Reply #35 on: 14 December 2008, 23:36:05 »

Looks like a plan. Step 2 will be expensive if you get it done, as it's a heads-off job. Make sure it's going to make enough difference to justify the cost first. Sometimes a standard head will flow well enough that porting only gives a return when hot cams are being fitted.

Kevin
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Albatross

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Re: Exhaust configurations
« Reply #36 on: 15 December 2008, 00:24:38 »

Quote
Looks like a plan. Step 2 will be expensive if you get it done, as it's a heads-off job. Make sure it's going to make enough difference to justify the cost first. Sometimes a standard head will flow well enough that porting only gives a return when hot cams are being fitted.

Kevin


Kevin,

Thanks for that. Is Chris right? Would I potentially end up with a "peaky" engine? I would prefer not to change the characteristics too much only to increase overall road performance.

I might even consider cams too as part of "Step 2", but again I would value your take on this too.

Nathan
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Kevin Wood

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Re: Exhaust configurations
« Reply #37 on: 15 December 2008, 10:01:39 »

Quote

Kevin,

Thanks for that. Is Chris right? Would I potentially end up with a "peaky" engine? I would prefer not to change the characteristics too much only to increase overall road performance.

I would say the manifolds you're considering won't have long enough primaries for length to be an issue. A quick fag packet calculation says they need to be 75cm long @ 6000 RPM. I might be wrong but that order of magnitude anyway. Significantly shorter than that and they will be operating in "non-interference". In other words, similar to the standard manifold with flat characteristics over the engine speed range but hopefully with better flow and less interaction between adjacent cylinders, so you shouldn't have to worry about them causing holes in the torque curve.

Quote
I might even consider cams too as part of "Step 2", but again I would value your take on this too.

On the whole, changing cams is a compromise unless the standard cam was extremely mild. Uprated cams typically shift the engine characteristics higher up the RPM range, so if torque is currently peaking at 3,000 RPM if might shift to 4000 RPM. If the "power band" currently starts at 2,000 RPM it might shift to 3,000 RPM. Assuming the head, valves, intake and exhaust system can flow the extra air required the torque will be at broadly the same value (it's a function of engine capacity), but because it peaks later, and power = torque x RPM you will have more power.

The extreme example is an F1 engine. 3 litre engine peaking at 19,000 RPM.. similar torque to a V6 Omega in all probability but all pushed up the the high end of the RPM range. A little more power, though :P, but has to be hept "on the boil" or there's nothing...

Driveability will suffer because the engine will be "flat" until the cams start working. With a manual box this isn't so bad, because you can drive round it. With an automatic gearbox it could get quite sluggish. I'd say given your goals uprated cams should probably not be on the list but this, along with everything I've said, is generic advice given without much knowledge of how this particular engine responds to tuning.

Kevin
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Albatross

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Re: Exhaust configurations
« Reply #38 on: 15 December 2008, 18:34:39 »

Thanks for that Kevin.

Ironically enough this ties up completely with the results of my phone calls to the 3 companies formerly mentioned above. I also ended up talking to the Technical Director at Mintek today too.

Upshot.

Advice from Mintek
Manifolds = Expensive and probably not too good an idea as they may increase the peakiness

Advice from the Exhaust company
A cross over at the mid-section would "balance" the flow.

Advice from the remapping company, UK Chipped
The standard ECU would not be able to be remapped to the extent that it would need to be to cope with the cams etc. so a new bespoke ECU would be required.

:oŁ:oŁ:oŁ:oŁ:oŁ:oŁ:oŁ:oŁ!!!!!  ::) ::) ::) ::) ::)



All in all the revised, and one single completely agreed from all fronts, plan is:
  • Fit new mid-sections with sports cats (Perhaps consider the cross over), but make sure that the cats are positioned correctly. If a cross over is fitted then further forward will increase torque, further back tends to increase power. The most important factor is exhaust operating temperature.
  • Do not do manifolds.
  • Do not do head-work and cams.
  • See what can be done to smooth the inlet from the plenum and intake manifold. I can try this myself, but I may ask for advice on here.
  • Get it properly remapped as SP_3.2 did at UK Chipped.

This pretty much what you originally prescribed, so utmost respect. :y

I hear what you're saying about the manifold tube lengths so I may revisit that with the mapping company and Mintek again tomorrow.

  • The final item that the technical people at Mintek and Chipped UK both independently raised was the suggestion to remove the tube in the air-box so that it is flush rather than protruding 6 inches into the air-box. Both of them said that this will instantly gain about 10bhp as it was fitted like that to conform to a specific psi range for company car tax brackets.


I have seen a fibrous tube in the bottom half and a trumpet shaped affair in the top half of the air-box. I'm not sure which one they meant. I have just removed the top half of the air-box and the "trumpet" slides straight out of the exit hole. I'm just about to drive it out of town to do an errand so I'll report back in half an hour. No harm done and the "trumpet" can always slide straight back in if need be.

[/list]


Thoughts?
« Last Edit: 15 December 2008, 19:34:22 by Albatross »
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feeutfo

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Re: Exhaust configurations
« Reply #39 on: 15 December 2008, 18:56:16 »

sorry to stick my nose in again, when did sp32 have his car mapped? His was exactly the same bhp as mine at the rolling road day iirc it was 189 at the rear wheels both measured on the second run. Mine is bog stock with a heavy foot fitted!
« Last Edit: 15 December 2008, 18:58:06 by chrisgixer »
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Albatross

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Re: Exhaust configurations
« Reply #40 on: 15 December 2008, 19:05:14 »

Quote
sorry to stick my nose in again, when did sp32 have his car mapped? His was exactly the same bhp as mine at the rolling road day iirc it was 189 at the rear wheels both measured on the second run. Mine is bog stock with a heavy foot fitted!


Quote
Yes Kevin is right i had my remap done about 2 years ago at a company called Chipped uk http://www.chippeduk.com/contact.php

Had a very good job done by them. They 1st put the car on a rolling road to check base BHP which was 232 they then uploaded the remap which  took about 30-40mins.They then gave it a 2nd rolling road which showed 243 BHP .

The  cost was about Ł250 it gave the car a better off the line pick up and better pull in D when you need it. They nice thing is that if you drive the car gently it is just the same as any other; it's when you open it up you know. As you said they are not many places that do the remaps for the 3.2...

...I would recommend these guys as they where very good; they took their time and made sure that I was happy with the change in the car and how the remap worked.
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feeutfo

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Re: Exhaust configurations
« Reply #41 on: 15 December 2008, 19:18:36 »

missed the 2 year bit. They are quoting fly wheel figures. The power at the wheels will be considerably less due to the auto box, but you know all that. Fairly certain Steves and mine where the same. He did post about coil pack trouble  between then and now so maybe its got some missing ponys back now.

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Kevin Wood

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Re: Exhaust configurations
« Reply #42 on: 15 December 2008, 19:40:33 »

One thing I would say about crossover pipes is that they do not simply balance the flow but provide another resonance that can help or hinder depending on the firing order of the engine and the exact positioning. On some firing orders (flat plane V8s, IIRC, for example), they don't work at all.

Personally, I would be interested to hear what the exhaust manifolds achieve. Hopefully someone on Autobahnstormers will try them soon. I can't believe they won't improve things because the gases exit the ports and have to turn 90 degrees with the standard manifolds.

Kevin
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SP_3.2

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Re: Exhaust configurations
« Reply #43 on: 15 December 2008, 21:42:19 »

Quote
missed the 2 year bit. They are quoting fly wheel figures. The power at the wheels will be considerably less due to the auto box, but you know all that. Fairly certain Steves and mine where the same. He did post about coil pack trouble  between then and now so maybe its got some missing ponys back now.

Good Point Chris

You are right they where the same and also about the Coil pack also had the plugs changed and replaced a unlocked injector plug which was giving a miss . All this was just after the Rolling road and it has very much helped with the missing ponys ;D ;D ;D.

Also have you hear of the trick with the air box and the feed in that Nathan came across.
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Albatross

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Re: Exhaust configurations
« Reply #44 on: 15 December 2008, 21:53:43 »

Quote
Quote
missed the 2 year bit. They are quoting fly wheel figures. The power at the wheels will be considerably less due to the auto box, but you know all that. Fairly certain Steve's and mine where the same. He did post about coil pack trouble  between then and now so maybe its got some missing ponies back now.

Good Point Chris

You are right they where the same and also about the Coil pack also had the plugs changed and replaced a unlocked injector plug which was giving a miss . All this was just after the Rolling road and it has very much helped with the missing ponys ;D ;D ;D.

Also have you hear of the trick with the air box and the feed in that Nathan came across.

It's possibly the feed out "trumpet" shaped piece that I should have mentioned. See my post above and my recent new thread that I have just started in trying to find out about this thing.

I've removed it temporarily and driven the car. It may be my imagination, but it does seem a little more responsive.
« Last Edit: 15 December 2008, 21:54:45 by Albatross »
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