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[Albatross]

There's a short stretch of dual carriageway near me and I know exactly how far I have gone down the road before I hit 100mph. That has just been cut by about 50 yards!

Think that is the Dual carriageway that I took your car out on a drive a few months ago checking out the mv6 springs and dampeners. .

Correct!

Have you noticed any change in noise  :question

Yep!

It seems to rev more freely generally, sounds much the same at low/normal driving rev range, but give it some wellie and it sounds ferocious. Bear in mind that I have the assistance of the stainless exhaust too.

[SP_3.2]

Yep!

It seems to rev more freely generally, sounds much the same at low/normal driving rev range, but give it some wellie and it sounds ferocious. Bear in mind that I have the assistance of the stainless exhaust too.[/quote]

WoW see what you mean, took the long was home after training and it does seem to make a diff with rev and with it over 4K the sound is good .

Have a long run into work so that should be a good chance to get a feel for things.

[Albatross]

I'm pursuing this line of questioning elsewhere (ABS) too just to see if I can get any further insight or wisdom. I have had a bit of feedback which concerns me slightly.

can't comment on this particular setup, but I know in many cases those trumpets although look restrictive will actually help airflow at the top end of the rev range and increase power (less air turbulence as the air is directed into the AMM)

Now don't worry too much as this is specifically in reference to the top half "trumpet" and not the bottom half fibrous pipe which was what I believe the Chipped UK man was talking about and that you have already had cut flush in your air-box Steve. The trumpet may be something that we shouldn't be taking out. Noise is nice, but not at the expense of performance.

I rang Chipped UK again today for further clarification, but the technical guru there who originally advised me was "away filming with Top Gear" for the day (How cool is that?). I will call him again tomorrow to find out exactly what his take is on each of the two pipes. He did say "cut the pipe so it is flush and you'll gain horsepower, it is there as a restriction".

The trumpet piece in the top does not need "cutting" so I am guessing at this stage that he was referring to the bottom pipe only given the quote above.

I'll update tomorrow.

[SP_3.2]

Good infor

Thanks   . As you said when i checked on my one the fibrous pipe was cut back. Car did seem to be fine at  top end  on the way in to work which is 90% motorway driving will keep an eye on things and check update.  

[ngrainqey]

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

i think the point behind a cooler running thermostat is to reduce overheating rather than a "performance" increase lol
hence why i'v bought one for when i try and melt some cylinders with a turbo

anyway... nathan, as regards the manifolds and intake/exhaust- if your running it naturally aspirated then yes you will need to tune the cam profiles, intake manifolds and exhausts to get the best airflow and get the most power but... that is usually expensive if you want it done properly

or you could play "lets crash the toy cars into eachother to see what happens" but with real cars and put a turbo/superharger on... which will mean that the exhaust and intake manifolds dont really have to flow very well as the blower will just force the air flow through regardless and it's just a case of how much boost you want (without going daft)

[Albatross]

I don't want to "go daft"; just mildly enhance methinks

[ngrainqey]

could use a s/charger or turbo to get a couple of psi boost which should run fine without remapping or anything

[Albatross]

could use a s/charger or turbo to get a couple of psi boost which should run fine without remapping or anything

I think that this was all covered off earlier in the thread TBH

[ngrainqey]

sorry to repeat things nathan, from what i got told the v6's are ok upto 6psi-no more, without any mapping just for reference  

[Albatross]

What you've been told from where?

[omegadan67]

Hi Nathan, interesting reading this thread I have a 2.5 manual saloon which i have played around with
1. lightened flywheel
2. reprofilled cams
3. ported heads
4. remapped chip
5. stainless cat back exhaust (sports cats)
6. modified viper ram air induction kit with relocated cold air feed
7. rollin road tuned

192 bhp and 187 lbs/foot, quick of the line pdq once on the move

Ive gone as far as I can go with out manifolds and/or turbo/superchargin then again there is nitrous.

All the above has had a a maked affect on performance not all of it good hence why i thought of turbo or superchargin, I have spoken to a exhaust maker with reguards to manifolds though the cost of these are beyond my budget at the moment.

[Liam]

Interesting thread.  I still would prefer to put a proper engine in mine one day - V8 .

Just one comment...

To put this all into context of what else is going on at the moment here. I'm also just about to fit an LSD which will change the ratio from 3.9:1 to 3.7:1. I'll also be changing the tyre rolling radius on the tyres by going from 235x35x19 to 255x35x19 which will compensate the ratio change a small amount.

Changing from a 3.9 to a 3.7 diff will give you taller gearing, i.e. slower acceleration/higher theoretical top speed.  Going to larger radius tyres will add to that effect, not cancel it out.

Liam

[Albatross]

Hi Nathan, interesting reading this thread I have a 2.5 manual saloon which i have played around with
1. lightened flywheel
2. reprofilled cams
3. ported heads
4. remapped chip
5. stainless cat back exhaust (sports cats)
6. modified viper ram air induction kit with relocated cold air feed
7. rollin road tuned

192 bhp and 187 lbs/foot, quick of the line pdq once on the move

Ive gone as far as I can go with out manifolds and/or turbo/supercharging then again there is nitrous.

All the above has had a a marked affect on performance not all of it good hence why i thought of turbo or supercharging, I have spoken to a exhaust maker with regards to manifolds though the cost of these are beyond my budget at the moment.

So what's been good and what's not?

[ngrainqey]

"235x35x19 to 255x35x19"
there's no difference in radius, only in tyre width

[omegadan67]

main bad points are PRICE for what i have done to the car i could have got another omega fuel economy or lack of it and 5000 service intervals,and exhaust  sound while cruisin can be boy racerish and boomy.

GOOD POINTS

quick very quick when floored very tractable the ideal sleeper car looks normal but capable of very swift travel the power to upstage bmws and mercs