boost gauge fitting

chopper · May 30, 2006, 10:48:58 AM

I have two boost gauges to fit (one for each turbo ) and was just wondering the best place to T them off ? My localgarage say its a mare without a ramp - but i dont want to book it in for something so easy

Has anyone got any pics of where they have T pieced them ? Or just some info would be great if poss

thanks again

mike

Fish · May 30, 2006, 10:51:27 AM

Why 2 gauges, as they go into 1 pipe.

Fish

chopper · May 30, 2006, 10:52:39 AM

i wanted to know Exactly what each turbo is doing tbh

chopper · May 30, 2006, 04:24:48 PM

No one posts much on here do they ?

Bump

Fish · May 30, 2006, 09:24:20 PM

People post plenty, not many if any have fitted gauges to each turbo as they feed the same pipe.

Fish

chopper · May 31, 2006, 09:53:10 AM

Well i like to do things different - theres two turbos under the hood so seperate boost gauges seems optional to me. Although i think ill go somewhere else for my tech advice as i cant believe no one has even done that before. I Used to run two gauges on both my 300ZX TT and my R32 GTR, its amazing the different readings you will get at different times. Still nevermind

Really glad i paid for membership two days ago

nikp · May 31, 2006, 10:30:02 AM

I\'m not sure if you\'d actually be able to do this. I have just been studying the vacuum and pressure diagram and have come to this conclusion. Basically, you won\'t be able to isolate the first turbo when they are both online. Whilst the second turbo you may be able to isolate, it\'s just not possible to identify the first turbos boost without the second.

Also, I understand you\'re trying to be different, but other than for troubleshooting purposes, it really won\'t benifit you. Not that i can tell, anyway. A single boost gauge will show all you need to know, unless you have an issue on the second turbo - I believe Martiny may have plumbed in a second boost gauge while he was trouble shooting his turbos, so maybe contact him.

The thing is, up to 4500 if you have 10psi then that\'s what the first turbo is doing. Ok, you could plumb in a boost gauge to identify what the second is doing here, but unless anything is wrong with your setup, you can assume it is doing nothing up to 3000rpm, and then pre-spooling up to 4500. Then there\'s a dip in boost as the second is brought online, and then once both are online it should read 10psi again - which means both are boosting at the same amount - any less and there\'s any issue somewhere. You may have boost trailing off towards the pper end of the revs, but that\'s normal.

So, as you can see, there\'s little point in two boost gauges for each turbo, unless you need to troubleshoot them.

Jit · May 31, 2006, 10:30:21 AM

err...if no ones done it, then no one can advise you can they? What do you want? Fantasy advise?

nikp · May 31, 2006, 10:36:48 AM

Quoteerr...if no ones done it, then no one can advise you can they? What do you want? Fantasy advise?

There\'s nothing wrong with being the first person to do something. After all, someone had to come up with the idea of replacing both turbos with a bigger single unit. But these things are only worth doing if there\'s something usefull to be gained from the operation. In this case, the reason it hasn\'t been done is that, unless you want to try and troubleshoot the turbos and require to know what the second is doing all the time, the is little point in doing this operation.

Jit · May 31, 2006, 11:02:22 AM

lol, i do appreciate that and i myself was looking to do this as well for that exact purpose...but what i mean is, i no one has done it, then how can you be expected to know how to do it perfectly? Ive looked at the turbo diagram one million times now (god i probably know it off by heart lol) while trouble shooting and i couldnt see anyway of isolating the first turbo like you said!

Prof · May 31, 2006, 12:03:18 PM

It works on things line 300ZX, because the turbos are for seperate halves of the engine - remember that\'s a V6.

The twin\'s on the FD run into each other, with the ultimate aim of pushing air up a single pipe into the inlet. So unless you are going down a very strange road and feeding each rotor with air indepentantly, then a single boost gauge is all you will need !

Remember that things still have to make sense - there is no point doing something to be different if it serves no purpose. :rolleyes:

A better mod would be to fit a couple of LED\'s into the boost gauge to indicate when the solenoids are fired for both the prespool point, and when the 2nd turbo switches in. You can then see what boost pressure you have at those points.

Cheers,

Prof.

DC-TYPER · May 31, 2006, 01:21:02 PM

like he said there technacaly a sequential turbo. one starts the other spinning.let me know how you get on.

chopper · May 31, 2006, 05:30:43 PM

its for the purpose of monitering a boost problem, and i will soon be upgrading both turbos to two bigger turbos, rather than one single unit. As i try to get power gains in different ways to the norm, to make myself feel like i have acomplished more. I always do it, my NA ZX was the most powerful in the country and to date no one has reached the power i got from it. I loved that buzz i got.

Obviously i wont have the fastest RX in the country, but i want 500hp from a twin T set up.

I didnt realise NO-ONE had done the 2 boost gauges before, i thougfh someone may have. I appologise if ive offended anyone.

And just to make you all happy ive put it on ramps today and thought "One will do" haha. I had a prob with the second turbo which ive now fixed (broken return valve) - so im happy.

I take it in that black box infront of the rats nest has got some electrics in it, because it seems a bit weird

Thanks again

mike

Oedipus Rex · May 31, 2006, 05:41:14 PM

Quote from: ProfIt works on things line 300ZX, because the turbos are for seperate halves of the engine - remember that\'s a V6.

The twin\'s on the FD run into each other, with the ultimate aim of pushing air up a single pipe into the inlet. S

what he said. I can\'t imagine anyway to isolate the first from the second. You could isolate the second turbo to trouble shoot that one but once both are spinning you\'re a bit shagged. Although you could take a reading from the second and then one from the first and second, then subtract the pressure from the second turbo from the reading from the first and second :Hammer . That would give you an independent reading for both, I think, or maybe not actually.

However because there is only one pressurised system, rather than two on a conventional twin turbo engine there is little point. To be honest a single gauge will give you all the info you need, as the first turbo spools up first and should get upto .7, if it does that then the first turbo is fine. At 4.5k the second turbo starts spooling and should be online by about 4.8. If you have a problem with boost after 4.8 but your early boost was fine then oyu know the problem is with the second turbo.

Fish · May 31, 2006, 08:49:44 PM

Quote from: chopperWell i like to do things different - theres two turbos under the hood so seperate boost gauges seems optional to me. Although i think ill go somewhere else for my tech advice as i cant believe no one has even done that before. I Used to run two gauges on both my 300ZX TT and my R32 GTR, its amazing the different readings you will get at different times. Still nevermind

Really glad i paid for membership two days ago

Well if that\'s your attitude, then fine. But you asked a question got an answer.

If you looked at the pipework a bit better, you would have seen that they join after about 6 inches of pipework. You can NOT get a stable reading in this space. IMO.

From memory the supra ran the closest form of twin setup and control to the FD.

Good luck with your project, but I doubt it will work that well.

Fish

PS. If you want REAL hardcore rotorheads, then try posting on the AUSROTARY forums! They will just cut you down before trying to offer advice.