4722 replies to this topic

[Nev]

Dont worry, heat wrap will do the job just fine, it's just a pain to get it all nicely twisted round each of the manifold pipes and locked down with steel ties to stop it unwrapping. I'm not very good with the jobs that require patience!

Edited by Nev, 18 March 2017 - 06:30 PM.

[Nev]

Got up at 5.30 AM this morning (yes I'm an insomniac!) and put the wrap on the manifold and re-fixed the bulkhead pannel, hoping to go out for a drive early this morning. Stepped out of the garage at 6.30AM only to find it raining.

 

I need to move to Spain.

Edited by Nev, 19 March 2017 - 06:35 AM.

[Nev]

Hmm, been for a few drives now, it seems to be more torquey at low RPM (ie 2000 to 4000), maybe a positive side effect of virtually no back pressure. Also, it's possible that my new huge flexi is putting less twisting strain on the GT3 turbo to exhaust manifold mount, which might mean less/no gas is escaping before the turbo.

 

Max backpressure I've seen is about 0.75 PSI, which is rather low, so I will be reducing the pre-load on my counter opposing spring to allow a bit more back pressure and a bit more quietness.

 

 

Edited by Nev, 21 March 2017 - 12:05 PM.

[Nev]

Took the extra counter-spring off today and took it for a little test drive this evening. The flap still opens by about 1 PSI of back pressure so all is good. Did 1 junction of motorway and the car is so steady at speed and fairly quiet at last.

 

I also tested the engine at steady 4500 RPM with no load on the engine, the inlet manifold was under vacuum so the butterfly valve should have been shut, but I suspect the flow down the pipe might be overwhelming the spring in the actuator. Hard to know without a camera on it - or someone looking at it.

 

Edited by Nev, 27 March 2017 - 07:09 PM.

[Nev]

Woo hoo, got spotted for the first time in years.

[ditonics]

I keep hearing you Are your over sized valves using the original seats recut or did you have to have new seats pressed in Nev?

[hairy]

I keep hearing you

 

All the way from Kent?

[Nev]

I keep hearing you Are your over sized valves using the original seats recut or did you have to have new seats pressed in Nev?

 

Amazingly the old valve seats had enough material to be recut.

 

I had to get the valves made bespoke as nobody did them at the time. I think now however you can get them off the shelf.

 

It is expensive doing as much headwork as I did (I think mine cost circa £2000 just for the parts + labour) but the head breaths so well as a result. Without any headwork you can get similar mid range power/torque by forcing more boost in, but by the time the engine is over around 6500 RPM the headwork comes into it's own. This is because the stock setup is tuned for peak VE at about 3500 RPM (which is great for economy, but crap for power).

 

A thing to remember with headwork is that extra valve lift and extra valve diameter increases flow at a roughly cubic factor, ie (Delta Lift * Delta Diameter * Delta Diameter). So when you both increase valve lift and valve diameter the flow rate of the head can really shoot up. Sadly I didn't get my head flowed before and after, so I can't prove it with metrics, but it's an age old recipe for power as I am sure everyone knows.  

Edited by Nev, 31 March 2017 - 05:52 PM.

[ditonics]

I get the impression the main bottle neck on our engines at high rpm is the inlet manifold design - long contoured runners. Good to hear your can cut the factory seats oversized. New seats are expensive and can drop if not done right. I've seen .5 oversized valves. I take it yours are 1mm over. Did you do anything extra fancy like a 5 angle seat face or a more standard 3?

[Nev]

The OEM inlet manifold is poor for power.

 

I had standard angles on my seats, nothing fancy.

 

Solid lifters with double springs and agressive ramps and long duration made a big diff on mine, though my idle is terrible (lumpy at 1100).

[ditonics]

How do you find the valve gaps change with time? Have you had to re shim then much? I hope for your sake it's not as often as a desmodronic Duccati.

[Nev]

I haven't ever checked or re-shimmed them, maybe some of the lash is too great now, but TBH the whole top end sounds like a bag of spanners being shaken around, just the same as the first day. I think one gets so used to quiet hydraulic lifters in modern cars these days, that listening to Nipper at idle can be a worrysome thing.

 

 

Edited by Nev, 31 March 2017 - 07:53 PM.

[ditonics]

If its anything like my old cars (rockers, pushrods, feeler gauges etc) it will sound like a singer sowing machine. All good fun.

 

More musing Nev, do you run the stock ECU and the standalone?

[Nev]

If its anything like my old cars (rockers, pushrods, feeler gauges etc) it will sound like a singer sowing machine. All good fun.

 

More musing Nev, do you run the stock ECU and the standalone?

 

The OEM ECU is no longer in the car, I just have an Australian Adaptronic ECU and a Brazilian ETB controller in there now (mounted behind the passenger seat on the bulkhead).

 

I was once fiddling with my laptop with the Brazilian ETB and had a question, so I emailed their support line, not really even expecting a response. However, much to my amazement within 10 minutes they replied and answered my question (in English). Good service/support like that is quite refreshing.

 

I have had a couple of queries whilst fiddling my Adaptronic ECU and contacted Chris (at EFI) who sold it, installed it and mapped it for me. He has also always been very professional and replied very quickly.

 

Edited by Nev, 01 April 2017 - 01:08 PM.

[jules_s]

I think you need to take him out in Nipper and scare the sh*t out of him 

[ditonics]

I'm leaning towards the emerald k6. Why do you have a different etb? Are you still electronic fby pedal? Trying to figure out how to keep the airbag functional and tie in the instruments way before hand.

[ditonics]

I think you need to take him out in Nipper and scare the sh*t out of him 

Once I'm happy with #64 again I'm sure I'll be going on a hoon to south Wales

[Nev]

I'm leaning towards the emerald k6. Why do you have a different etb? Are you still electronic fby pedal? Trying to figure out how to keep the airbag functional and tie in the instruments way before hand.

 

Yep, many ECU's can't manage ETBs, so I had to have an ETBC in order to keep my 70mm Bosch throttle body. There is no way I'd want to install a wire operated TB on my car, loads of difficulty doing so and a technical and maintenance step backwards IMO.

 

I know nothing about Emerald ECUs I'm afraid, but they are certainly a prolific and long lasting company.

Edited by Nev, 01 April 2017 - 02:05 PM.

[ditonics]

It will run the fby pedal and etb which is a bonus. Any more work on Nipper?

[Nev]

It will run the fby pedal and etb which is a bonus. Any more work on Nipper?

 

I seem to have some oil mist appearing on the side of the block from somewhere, likely culprits are the dipstick entry point into the block or possibly some oil connectors that supply the turbo. I've made a minor fix to the dipstick and have a new one to replace it with if the problem persists.

 

Weather looking good tomorrow morning, so will likely go for an early morning blast. Getting up at dawn and having virtually traffic free roads is such bliss - must be like when my dad was driving round in the 1950s.

 

 

 

Edited by Nev, 01 April 2017 - 02:14 PM.