The fluid filled gauges are better for dampening pulsations, like in the fuel system. While the exhaust has pulsations, it won't be as harsh as that in the fuel system. There usually isn't rubber in gauges, so I wouldn't be too concerned.

As for holes in the manifold, I wouldn't be worried about that either. The 24v manifolds usually crack on the divider between the front and rear cylinders. Not sure where the 12v manifolds crack, but you should be ok anyhow.

 

I have two holes drilled in my ATS manifold. Where are you planning on drilling at? I think you'll be ok with two holes just keep them some distant apart from each other. The ATS manifold is alot beefier than stock, so I had two holes drilled at the mouth of the turbine flange. My stock manifold, I drilled up on the runner abit more towards the head. I'm using cheap fuel pressure gauge from autometer, thats has teed right off the injection pump and thats has a 6ft chuck of stainless 1/4in run directly into my fuel gauge, no isolator, just straight to a gauge (been there for four years, no issues). I would have a gauge after the filter, so you know the injection pump supply pressure. A gauge before the filter would help to tell you when to replace the fuel filter as you can measure the differental pressure across the filter. The dP will increase as the requirement fuel flow increases.
You running stock 12v lift pump, and stock fuel lines? What does the fuel pick-up look like in the tank? Mine had a bunch of trash on the suction screen. I run a VP injection pump and you need lots of fuel to cool the pump down. Most gets bypassed back into the tank.

 

I'll put it on the x here. It's a stock manifold.

Oh, you have a 6' coil of SS before your FUEL guage? That must dampen the pulsations, right? I wouldn't need that coil if i used a needle valve I think.
I still can't decide if I want a temporary install or permanent.

If I do have low fuel press. I'll have to check the tank, good call, thanks. That and the fuel heater. I think there is a screen in there too right?

I thought you had a coil before the drive pressure guage. Would 3' of 1/4" copper isolate a drive pressure guage from heat enough? How about a soot trap, need it or not? Not required if I use 6'?

 

Oops, I forgot that I have a needle valve thats pinched down some. I just ran mine thru the firewall, no coil. I'm guessing at 6ft, could be 5ft. Its a straight cunk of tubing. There is no needle bouncing and the only issue is when I have freeze-up on my fass filters. That darn water liquid freezes up in the water seperator and block fuel flow at below -20C. Had it happen twice last year.

As for drive pressure I didn't run it long enough to get soot plug up. You'll see it happening on the guage. Soot covers all and everything. I had some leaks on my exhaust. The soot is acting like a sealant.

That area looks far enough away from the other hole. If it breaks, I'm sure we can find another one for ya.

 

So a drive press. gauge really just needs to be a temporary diagnostic tool?
If so I could just remove the pyro for a couple of pulls,
use a soot trap and small copper coil on my boost gauge to get a diagnostic reading, and put then put the pyro back in?

And the oil pressure I would have to get a real gauge so as not to get oil in my electronic X-monitor even though it may work to read oil pressure too?

 

Oh, and Mike, to answer your questions about my lift pump and lines. Yes they are stock. The previous owner said the lift pump was replaced recently (year or 2,3??)
I've read on the forum the stock lines are good enough for my hp level (500) so I don't think they are holding me back.. I just want to temporarily remove the AFC and cover it with a rag see how much smoke is made. Then maybe pull out the fuel plate and see if that makes any fueling difference.....
Steve

 

There are a few hardcores that use one just as often as a boost guage. It sure will tell you information that good for tuning up the truck. Get back to us on how well that your turbo makes boost. If you have no boost leaks and the everything is working you should have a 1:1 ratio till 40-50 area. Keep us up to on your findings. Mine matched pretty closely to the boost pressure but my truck only built around 60psi of boost at the time.

 

If you are using it as a tuning tool, I'd rig something up so its through the hood so you can see it, and your pyro and boost is still visible. Otherwise you are tying up your right hand just so you can use your left, so to speak.

If you want full fuel, pull your AFC off, pull the 10mm bolt on the front, out comes the slide pin, and the foot drops out. Reinstall the pin, bolt, AFC and you have a gutted AFC. Beats the hell out of using a rag on top. Try it, but you will want to go back to a tuned AFC after you stomp on it a couple times and don't go anywhere fast.

 

I would the boost gauge and drive pressure gauge beside each other. Usually at high boost situation, your doing a decent speed and the road is going by pretty fast. Kinda hard to look at all the guages. You can put a rubber hose or plastic hose so you can connect it into your dash. The heat from the line would have disappated with the 4 to 6ft of stainless/copper coil.

 

OK, thanks. So it looks like it's best to pull the turbo so I can drill and tap another hole. Then just stick a plug in there after.

Scored some real cheap gauges yesterday... some used 4" guages from the schools boiler room! Kind of chunky but they'll work for testing. Also found a few feet of copper and plastic 1/4" tubing and some brass fittings to make it all work.
Just need to get a bleed valve now.
I found out the is a Acklands\Grainger in Ft. Mac as well as Gregg dist.

Yeah, come to think of it that probably is better, Tate. I thought I could just pull off the AFC for a second and start the truck to see if I can get any coal out of it...
But I remember now I have to pull the fuel supply tube from the p-pump cause the AFC has to come straight up before it can come back and out...
Oh, well, at least I can tap the banjo bolt at the same time, thanks for all the suggestions guys.

I am sure I must be down on fuel pressure or the diaphram in the AFC is ripped; I get next to no smoke at any throttle setting....
http://www.youtube.com/watch?v=gHUGjtqCfnI

Steve

 

Without having them checked you have no idea if they are even accurate. If you are doing testing, you NEED accuracy.

You can either go to an instrumentation company in Ft. Mac (Ber Mac, Pyramid, Emmerson Process....) and have them tested, rent a druck to test them yourself (I can tell you how Steve) or just buy new ones.

You should be able to get a basic pressure guage for less than $20.

 

Thanks for the tip Doc. I hooked a couple of them inline with a new gauge and a schrader valve on the other end with bicycle pump. They all read within a pound or two of eachother.

If I take them in for testing or rent a tester there goes my "cheap" aspect.
I am hoping they are close enough to get a drive pressure.

I know dividing exhaust pressure over boost, say 50 over 40 yeilds a ratio of 1.25. Good for spooling not so good for top end hp or egt.

If the DP over boost is 35 over 40 it yeilds a .875 ratio. Not so great for spooling but better top end power (dyno).

This is how it's calculated, right?

I see it doesn't take much gauge error to throw the ratio off, but I guess it's the Scott in me that doesn't want to pop for new guages I'll use once.
Steve

 

Ok, if you checked them they should be ok. Being out a pound or two on a 100 psi guage is pretty much normal.

 

OK, typical then. I also managed to get a couple of old school brass petcocks freed up and turning again. Had some green scale on em', that's all!SO i'm good to go.

 

Drive pressures don't really indicate whether a turbo spools well, or has good top end, it tells you how effeciently the charger is working. If it stays close to 1:1 until 45 psi, then suddenly jumps, then you can start to tune around the limits of your charger. At that point, an external gate would be beneficial, or a second charger.

As for drilling another hole in the manifold, I'd drill most of the way through, start the truck, then finish drilling, and tap it. Wear safety glasses when you do this. If a few cuttings happen to go into the manifold, its not gonna be the end of the world. There is lots of room in the turbine section, only a single stage, and low velocity when its idling. JMO.