Valve springs

[Benz]

I moved my boost/vacuum gauge to the engine side of the throttlebodies,[instead of using the boost sensor outlet at the back of the plenum] and noticed immediately there was some flutter showing on the gauge at idle, and got wilder as the revs climbed. I assumed I had a leak at the rubbers, so I did not worry about it at first. I've since installed a power commander111usb,and 350cc high impedance injectors, so naturally while I had it apart I redid the rubbers to head connections, and fired it up. The gauge still fluttered........
So....the head is off to inspect the valves to see if any are bent, burnt, or the valve seats were not right. They seem to be okay, the exhaust valve seats are black, but I can see where they are sealing [ I will lap them in anyway].
My question is, could the inner and outer inlet valve springs touching/binding against each other, cause poor valve sealing, making the vacuum gauge flutter, and the engine to run roughly once warm?
My inlet springs have heavy wear showing, and the inner spring is binding against the outer, to the point where it was extremely difficult to separate them. The inlet outers are taller and slightly narrower than stock[I have spares from another engine to compare with], yet the exhaust springs seem fine, they separate easily, and have next to no wear showing.
I have put up with this engine being rattly virtually since I had it rebuilt, I've taken it back to the builder, who said it was as quiet an engine as he's heard, for an air cooled Geep 810 turbo, but he spent two seconds listening when it was cold, and the oil pressure high, as opposed to when it's hot and sounds like a bucket of bolts!!
I suspect he has installed higher rated [but wrongly sized] outer springs to the inlets only, and charged me for a complete set of springs....:( and the binding is the squealing/rattling noise I've been listening to all this time.
Any thoughts??

[Booster]

Vac gauges bounce lots if no damper is put in the signal line, thats normal,seen a few loose the gauge needle off its pin
picking up from several throttlebodys rather than one will improve it or plug the vac line near the throttlebodys with an idle jet or similar so there is a small hole near the TB's and a larger chamber (vac/boost line) to the gauge

[Benz]

Thanks Booster, it's good to get confirmation before I sling it back together. My setup already picks up from all four throttlebodies, but has the adjustable fuel pressure regulator,and the compressor bypass BOV valve feeds running from here as well as the boost/vac line . I will reduce the feed line size to the gauge at the t-piece, and see if that helps. At least I know all will be good under the valve cover, after I replace the dodgy outer inlet valve springs with spares I have, and lap the seats in.

[Booster]

Do you have or can borrow a spring tester,check them all if you can and see if there is enough room at full lift for shimming
i have used 1mm stainless washers several times to beef up stock springs , on my old trackie 600 it was the difference between bent valves and not

[Benz]

I've put it back together using the stronger inners, and stock outers on the inlet valves,[the stockers leave enough clearance to prevent wearing against each other] and the original springs going back on the exhaust side. There are 1mm shims already under all the valves, so I know they are stronger than stock,but I just couldn't live with the knowledge the inlet springs were constantly grinding/binding against each other.
The old girl never sees more than 10k, with most of its work done between 5 and 9, so valve bounce/float shouldn't be an issue.........hopefully.
I guess I'll find out this Sunday, when it does a trackday at Hidden Valley. I'm still yet to get a decent map into the Power Commander, so I'd better get my arse into gear!
Thanks for your help Booster, much appreciated.

[Booster]

No Probs mate, think you had most of it sussed anyway , just the gauge throwing you off..
Enjoy the trackie , Livewire is doing one near me this weekend and i will be in WA , dunno why they always come up when i'm busy lately,

[Deano]

use a liquid filled gauge and it will be solid as a rock if taking signal off all 4 ports

[livewire]

I always put petrol in the chamber when the heads off to make sure valves are seating.

[Benz]

Thanks Deano, will do.......don't happen to sell them do ya??
How's your turbo Gixxer workin for ya?
I've put an idle jet from an old DGV weber in the boost/vacuum gauge line for the moment, that should slow it's movement down enough to be able to see the needle!
I'm fairly sure there will be no leakage, I got a good clean ring around both the seat and the valve after lapping them, and they weren't that bad to start with.
Will be firing it up tomorrow morning, spent all day putting it back together, just the tank and covers to go........and mapping the Power Commander,[fourth attempt] of course.
I wish there was someone in the NT I trust enough to do a dyno run....the bastard who built this nightmare is the 'go to guy':(
I'm using the OEM boost sensor to signal the PC, after installing a small resistor bridge to get the 7 volt signal to the ECU [who uses 7 volts??, it is a 1984 model, I s'pose] back to 5,so the PC doesn't cut out, and I have enough fuel map to push the little mongrel to 32 psi if I want to handgrenade it, but for the moment it will run out to around 22psi which should see plenty enough fun.......:)
Thanks guys