12 psi. max?

[Turbo-Rich]

What gives
I've adjusted my wastegate rod in as far as it will go & I still can't make no more than 12 #'s of boost
When I had the turbo off it seemed to be in good shape.
No scars & not much "play" in it.
I have a spare turbo I can try but I thought I'd fish for some idea's here first.

 

[b4black]

Intake and exhaust restrictions. What do you have for an air cleaner (factory box or cone?) and exhaust (convertor)?


All closed up with factory stuff makes it even hard to get 9 psi sometimes. The WG is almost un-necessary on a stock car.

 

[Scott Adcock]

Check for any exhuast leaks. I know they usually make some noise, but not always. I had an exhaust manifold gasket blow once at the dragstrip, right after the launch, before the 60' mark. Man did the car fall flat on its face.

The factory stuff is pretty restrictive. I did notice a gain by switching from the stock air cleaner assembly to a cone style, drawing air from under the front bumper. I also changed the exhaust manifolds to an '84-85 type setup, noticed a gain as well. I can get about 16-17psi out of the stock turbo.

A looser converter in the trans would help as well.

I would think the cam would have some influence as well?

 

[Turbo-Rich]

Thanx for advise guys
I did just change my header, maybe something is leaking a little?
I don't hear any leaks though, I still might re-tighten everything.
Right now the car only has a downpipe for exhaust, no cat. or muffler. I am still (temporarily) using the fact. style air cleaner assembley.
I considered what B4Black said about it being restrictive so I removed it completely for a few passes Sat. morn.
I still couldn't make no more than 12 #'s.
Other than that she's really running pretty good.
The car makes 9 #'s in first gear then shoots to 12 #'s in 2nd & 3rd.
I can make 2 #'s of boost on launch & nicely haze the tires if I want to.
It is running a little rich though. My O2 meter & my plugs both agree.
Maybe that could have something to do with it. The carb. didn't seem to be in real good shape when I had it off. It was gummed up quite a bit & the only thing I did was to it was give it a cleaning. I have another style of carb. I want to try on it but I wanted to make sure everything was solid motor wise & I was hoping to max things out with the q-jet & stock ign. (ecm) first.
I'm planning on adding a pressure controlled boost controller also.
(quiker spool)
Maybe that will help some?
I have 2 extra (used)wastegates. I might give them a try also.

 

[Turbo-Rich]

Originally posted by Turbo-Rich
I'm planning on adding a pressure controlled boost controller also.
(quiker spool)
Maybe that will help some?
I have 2 extra (used)wastegates. I might give them a try also.

I added the boost controller http://www.dawesdevices.com/boost.html
but it made no diff. in max. boost pressure.
Wastegate must be ok since the boost controller was completely holding the signal back from the wastegate & max. boost didn't change any. It did seem to have more low end power & spool noticeably faster. I think I'll add one to Tonya's 'T instead of hacking up her wastegate rod. I'm going to build the next one myself. I bought this one more or less a a model to go by & I wanted to see if it made much diff. I should be able to build one of these for about $10-$15 bucks from McCasters.
Back to the my 12 psi. max situation.
I believe it's mainly caused by my turbo being old & worn. I've been digging through old archives in all my turbo clubs & I've come across other T-3's making low boost pressure before a rebuild. My turbo looks to have never been rebuilt, no tags anyway & pretty rough looking. I have a spare that has a fairly recent rebuild on it that I know the guy was making 15 #'s with. This one DOES have a rebuiders tag on it. I need to get a bolt extracted from it first then I'll switch them out. If that doesn't make any more boost then I'll prob. start working on getting the other carb. combo on it. I need to add an elect. fuel pump & I'm going to TRY to keep the stock ign. in it @ first.
There are a few smaller things I'm going to try first (more timing, etc.) but they will prob. prove to be nominal in my search for more boost.

 

[Turbo-Rich]

Maybe I jumped the gun just a little.
I've put off deciding where to mount my vdo tach. so I haven't a clue what rpm I'm shifting at other than by "feel" from comparing it to Tonyas 'T .
I did a good adjustment on the T.V. cable the other day & picked up another lb. of boost. It's pushing over 13#'s now & I believe I've found an exhaust leak where my up pipe meets the header.
That's got to be killing my spool up & my max. boost pressure. Anyone have any advice on up pipe sealing Ultra Copper is only rated to 750 deg. I believe so I'm not sure about using that. I do know some of you guys swear by it though. I guess if it can seal a header to the head it can surely seal an up pipe
Once I get that taken care of I'll G-tech it to see where I'm at.
I've been hesitant to do full 1/4 passes with no exhaust on the car @ 5:00 in the morning
Before I go too far I'll get some kinda exhaust on it & it needs new front tires & an allignment. Safety first~right.
It's hard not to get on it though, even @ 13#'s she feels pretty strong.
I also have purchased an elect. washer pump to add to my alc. kit that will be triggered by the fact. hobbs switch.

 

[Scott Adcock]

I have used the ultra copper with good results. I have used it where the header meets the head with no problems so far. (Knock on wood!)