V8 Stylus Build

[MattD]

During the test...

And what was left after taking a few bits & pieces off .....

Positive overall, and the job list isn't earth shattering... but still annoying not to pass.

Failure points being....
Mismatch of emissions for each bank of the V8 - failed on CO2 one side & H/C on the other (despite have been setup for MOT).
Seat bolts not marked with thier grade - 8.8, etc and the inspector wanting to see 100x100x4 load plates.
various wiring tidying - such as putting more sleeving on, supports, etc
one place in the tunnel where the brake pipe rubs the chassis.
Fog light working with sidelights only (should only work with dip & main).
All digits of VIN number stamping not clear enough & not on right hand side of chassis - gonna stamp & weld a new plate in.
Biggest one - failure on noise - 101db one side, 102db the other - 99db allowed. Its going to need a rethink in silencers

Oh, & a strip down on the upper steering column for inspection during the re-test, as he can see how its mounted.

[stylussprinter]

My guy just looked under the dash with a mirror and torch to see the column mounting Where do you go from there regarding the emissions Who set it up for mot I bet he's pi ....... ed off not getting a pass .

[kevp]

I also had to stip my dash & access panels for the tester to inspect the stearing mount & pedal box.
Also had to get certification re eye bolts for seat belt fixings.

Good luck on the retest, hope its easy to sort the noise & emmisions out.

[josephmoore]

I really know nothing about IVA requirements but would it be acceptable to fabricate some bungs for the exhausts? Could be enough to bring the noise readings down?

[MattD]

I really know nothing about IVA requirements but would it be acceptable to fabricate some bungs for the exhausts? Could be enough to bring the noise readings down?

Might completely screw the emissions though !

[josephmoore]

Surely the emissions test is just measured as a percentage or parts per million? If that's the case an exhaust bung's just going to restrict gas flow (and reduce noise) but won't actually alter the ratios of gas and particulates. Like I said, I might be totally wrong as I've not had any experience of IVA stuff.

Just to clarify, by "bung" I mean this:
http://www.sumopower.com/uploads/produc ... haust-.jpg

Not this:
http://www.racespec.co.uk/acatalog/t_Pr ... stBung.jpg

[MattD]

Surely the emissions test is just measured as a percentage or parts per million? If that's the case an exhaust bung's just going to restrict gas flow (and reduce noise) but won't actually alter the ratios of gas and particulates. Like I said, I might be totally wrong as I've not had any experience of IVA stuff.

Just to clarify, by "bung" I mean this:
http://www.sumopower.com/uploads/produc ... haust-.jpg

Not this:
http://www.racespec.co.uk/acatalog/t_Pr ... stBung.jpg

Yep, see your thinking. There's no room for something like the sumopower part though.
Was considering shuvving some wire-wool up the pipe to see if it makes a difference.
Probably wont stay there for long .
I all looks "temporary" too and the inspector wont like that.

My concern on this route is that the the exhaust back pressure is increased, and the gas mixture escaping from the cylinders is restricted (& thereby enriched), messing up the emissions. But.. carb settings could be changed to get round it.

[MattD]

I also had to stip my dash & access panels for the tester to inspect the stearing mount & pedal box.
Also had to get certification re eye bolts for seat belt fixings.

Good luck on the retest, hope its easy to sort the noise & emmisions out.

Cheers Kev.

Yes its the steering & pedal box he want to look at, so obviously on their list !
Interestingly... its a new guy at Yeading... trained by the guy from Southampton.

[MattD]

My guy just looked under the dash with a mirror and torch to see the column mounting Where do you go from there regarding the emissions Who set it up for mot I bet he's pi ....... ed off not getting a pass .

Hi Rob

Yep, I made sure the under dash was fully boxed in, so no chance of getting need heater & wiper motor, etc..
We took the column cowling off top & bottom, but that wasn't good enough for him to see !

Most of its niggly stuff, that an afternoon or two will fix - he's probably at home right now doing them

Emissions should be just a case of balancing the carb to the VOSA spec - guess each test machine is slightly different. And of course, its a recent rebuilt engine & new carb, no mileage, so its still running in.

Noise is the the big job. Could be simple , could be remake with additional or bigger silencers.

[stylussprinter]

It only failed by 2 db's which is bugger all to lower. Where do the twin pipes exit from the car ----- side or rear exit If rear exit but not repackables then simply cut out a length and pop in another cherry bomb silencer each side . Also each side/bank needs to be joined to the other/a crossover pipe --- helps balance everything on V8's .
If repackable then it's dead easy --- just repack with basalt

[CMA]

instead of expensive rebuilds or new cans, why not try a DB killer insert. Or even cheaper just bung some stainless pan scourers up there and secure them, they obviously "fall out" on the way back from a sucessfull test. This will kill the sound and I know alot of people tha have done that.

[MattD]

No room for a decibel killer, the cans are in each sill, with a exit pipe 90deg downwards straight out of the box.
The scourer idea is kinda what we were thinking when I said wire wool above.
Will prob try this out.

If not will likely put a small cherry bomb in each manifold 4-1 exit pipe.
Wont cost that much to do, the whole system is mild steel.

Stage 3 is bigger repackable cans, but a few other options first.

Rob > 102dB is twice as loud as 99db. Or another way 105db trackday is 4 times louder than a 98dB day
It's a log scale of measurement.
The V8 is quiet compared to a bike, it's the low rumble that's the problem I think.

[stylussprinter]

Simon Besant's V8 with all that huge grunt tests at 98 static --- it's only the circuit db sensors that prevent him running at Goodwood . There's loads of low down rumble in his . You could have a word with him

[MattD]

Another IVA surprise in the post last week

There's a note on the posted written fail about being "over" on the design weights.
I filled out the form for what I thought was the usual - 500kgs front, 500kgs rear, 1000 all up.
This is meant to be for the car fully loaded - something like 75kgs each seat, plus 25 for luggage.

Apparently they've calculated the rear axle to be 517kgs, inc this allowance.
Not sure on whether the ministry red tape can be bent to just amend the form to say 550kgs rear & sorted !

Unc had the car on the local weightbridge yesterday - surprisingly balanced - 720Kgs all up 360f/360r (420 rear with him in it)
So... take all the fuel out, take all the washers off it, possibly fit a different set of wheels - all to lose 17kgs+ quick.
Any other ideas

He's also been busy on all the other little niggly jobs, and had the carb mildly tweaked in line with the noted emmisions req.
Exhaust is now sorted we think - Unc has fitted 2 decibel killers on the input to the sill mounted cans, just after the exhaust manifolds. Apparently its "much" quieter - I'm going to measure it with my noise meter later.

[MattD]

Was hoping to say it passed today, but no such luck

Passed 14 of the 15 failure points, including the noise & weight problems.
But still failed the emissions test on CO being too high, despite having been setup again by a local garage & having the print out to prove.
To be fair, the tester ran the test 3 times, but to basically the same result.

So some head scratching to do.... possibly remove 4 barrel Holley & revert to SUs for the test.

Well at least she looks good on the £800 worth of lighter wheels & list 1B rubber