Yella's ZX7 project

[mr.zxr]

it makes sense. remember the wastegate actuator works on psi(ponds per sqare inch) and if you reduce ID of the hose you reduce the sqaure inchs therfore reducing the force on the acuator. but if the motor is handling it, leave it. like said to you on the phone my 750 with 1.2mm spacer saw over 20psi a couple of times and never missed a beat.

[latheboy]

I'd keep an eye on your AFR meter if its spiking to 14psi. Rad i hope the motor holds up, then you can just run it at 14 all the time...

It's odd that it spikes so much, do you have the same size pipe from the waste gate to the pick up?

[latheboy]

I don't remember typing that last post ....

I know i bang on about the AFR's a bit and it's much easier for me with my job, but I just don't want anyone to melt a motor.

[Yella]

Will be putting the gauge on over the weekend with any luck and seeing what goes on will post up results

[ozzy1100]

what u will find is not that psi changes with small hole but flow rate will change therefor u will get a spike
presure does not change with pipe size in a sealed system flow yes but makes no dif presing agaisnt a dead end
what might be happening is that the t piece cant flow enough air to fill the volume of the waste gate diap fast enough
sounds funny but you can change pipe size between two piont and have psi and flow remane the same the only thing that changes is verlosity it do my head in some times working out fuild system lol
none of this makes any diff to u fixing because u at the same piont just one of my pet jobs at work lol

[Deano]

what u will find is not that psi changes with small hole but flow rate will change therefor u will get a spike
presure does not change with pipe size in a sealed system flow yes but makes no dif presing agaisnt a dead end
what might be happening is that the t piece cant flow enough air to fill the volume of the waste gate diap fast enough
sounds funny but you can change pipe size between two piont and have psi and flow remane the same the only thing that changes is verlosity it do my head in some times working out fuild system lol
none of this makes any diff to u fixing because u at the same piont just one of my pet jobs at work lol

That's pretty much what I thought to

[mr.zxr]

that makes sense

[Yella]

So got out today 3 things became apparent
1st when you give it more boost its fun with capital FFFFFPPSSSSHHHHH
2nd I really need to invest in a data logger it's interesting looking at all the gauges with the front wheel trying to get over your head
3rd if you hit the remote start stop button in your pocket with your fat gut as the front wheel comes down things get interesting and you piss a large amount of smoke out the pipe.

Anyway first run as it was with boost spike A/f never got past 11.4 so I was happy and adjusted the bleeder.
First run 3rd gear 10psi front lifted had to back off
Second run same could have held it but trying to read everything decided to try to do it with both wheels on the ground
3rd run this time 4th gear 14psi boost came on front came up but kept at it A/F stayed at 11.4
Idle 14.5
idle to 1/4 12.9ish
1/4 to 1/2 11.8ish
1/2 to WOT 11.4 and holds all the way to rev limiter
Cruise at 110KPH it sits at 12.4ish
As boost comes on it drops down to 10.something I think its 2 or 3 but hard to see

As said I need data logger or dyno time to confirm but looks goods so far hope to book a run on the dyno soon with A/F meter fitted so I can get a graph to post up and I will video the run aswell.

Also heading out to E/C dragway this month to see what it can do I'm gunna run it at stock boost and at 14psi just cause I can

[hyofighter]

all this boost talk is getting me excited , nice work yella all that hard work is paying off now

[LKC73]

Shit yeah mate, sounds like you ahve this thing running nicely. Let us know when your there at EC for drag night.

[slingy88]

Great work Yella,

Give yourself a big pat on the back An awesome insparational build that will get many people hunting ebay for turbo's i'm sure LOL.
Just hope mine ends up going as good

Keep it up

Slingy

[Yella]

Thanks Slingy.

Went out for a run today 40degree day figured this would test it out, all was going good until about 5mins from home notice my right leg was wet bike wasn't running hot but was pushing out some water so kept on going home. Not sure but the clutch seemed to be slipping aswell could have been the the bike was not 100% but will need to look at that aswell
Pulled up at home and water was running out the overflow bottle anyways put it in the shed let it cool a little and took the cap off fired it up starts and runs sweet but it is pushing water out the radiator looks like I have blown a head gasket into a water jacket . Did a comp test all are even but my snap-on rad tester does not fit the Kawasaki so I will bring one home from work tomorrow and confirm.
The first of the weak links. I want it stay running the higher boost so will need to look at a better head gasket or something to help.
So the fun will begin again. I need one of you fuckers to live closer to help with the heavy lifting last time lifted the motor in on my own nearly killed me.

[rod185651]

Mate, if you can wait I can drive down sat afternoon and help

[BANDITROD]

fuck that sucks yella i hope you get it sorted mate

[Redmohawk]

Time for anealed copper and O rings ?

[EXBEN]

Yella, are you running an intercooler ? if not I suggest you start looking at fitting one, if you want to keep running that kind of boost reliably, either that or water injection but a cooler would be cheaper. The stock head gasket should be more than sufficent.Maybe use a bit more torque on the head bolts & some copper coat on the gasket.

[LKC73]

Yella, your a Sydney sider arnt you? If so all you have to do is give me a bell and tee up a time mate. I would be more then happy to help a fellow fighter work on there bike!

[Yella]

Yep I was thinking about it last night will have to back the boost off back down to standard until I can get the $$$ together for rad/intercooler set up.
Put copper coat on it last time will get it out and check it out bang it back together all good.
Thanks for the offers of help will let ya's know when it is need

[slingy88]

Yep I was thinking about it last night will have to back the boost off back down to standard until I can get the $$$ together for rad/intercooler set up.
Put copper coat on it last time will get it out and check it out bang it back together all good.
Thanks for the offers of help will let ya's know when it is need

Man, it sucks that you had the such success with the extra boost only to have head gasket trouble

From what i can make out, its not so much an issue with the gasket but with the extra cylinder pressures lifting the head which then causes the gasket to fail. I'd of thought either more tension on the cylinder bolts as EXBEN said or even better, larger stronger cylinder bolts which would stretch less at the same tension with a standard head gasket would be a better option. I've read that the Busa boys are just using high tensile socket head machine screws for cylinder bolts now a its heaps cheaper than aftermarket ones and in some cases stronger to.


Anyway, mate good luck with sorting it.

[Yella]

Motor out, head off, checked, cleaned, new gasket, copper coat, head back on, rest. Motor back in tomorrow and test ride