foot brake boost

[87GNcospg]

not sure if this is a transmission related issue or a turbo issue. . . .
i have a hughes tq converter installed in my car. i asked for a 3000-3200 to be installed. i decided to test the stall on the converter. i kept my foot on the brake and started giving it some gas. i got it up to about 3400 rpm (?) and the boost gauge was reading 0 psi. i was doing this for about 8-10 seconds.
first of all. the rpms are being read with a scanmaster from racetronix. is this a reliable rpm gauge to be using just to see stall rpm? yes i know there is a delay.

shouldnt i be seeing some boost on the foot brake?
car is mostly stock with a PT63E. heavy duty build on the transmission.

 

[suicide six]

What was boost gauge on instrument panel reading if so equipped?

 

[suicide six]

I would say scanmaster rpm reading is correct,What happens above 3400?Has the car been driven prior to taking readings?Any boost indication prior to testing stall.I would say you have an indication problem.

 

[87GNcospg]

the stock boost gauge was not registering anything. i did notice earlier that at about 8psi on the aftermarket gauge the stock one was only showing 1 orange click. this was not stalling the car. this was just driving around.
i am thinking it may be a wrong boost reading also. what else could it be?
i used to see 3-7 psi with the stock converter before it blew up.

 

[2QUIK6]

I notice you have alky, if you have Razor's setup, the stock boost gauge will only be reading half of what it actually is (providing that it was fairly accurrate in the first place)...because Razor uses a 3 bar MAP sensor in place of the stock 2 bar.
You tune will have a lot to do with how much boost you build and how quick. With a 63 turbo, you probably are lucky to see 8# at 3000-3200 rpms on the brake. Your rear tires should break loose when the stall speed is reached.

 

[87GNcospg]

im almost certain the stock boost gauge is a peice of junk anyways and is way off. at 3400rpm im seeing 0 boost (with aftermarket gauge) what types of things should i be looking into to resolve this problem?

 

[Blazer406]

im almost certain the stock boost gauge is a peice of junk anyways and is way off. at 3400rpm im seeing 0 boost (with aftermarket gauge) what types of things should i be looking into to resolve this problem?

I would mash on it til it started to build boost.....unless it went over 4500 RPM or something.... then I would definately look at converter problems.....

My "0-pump" vigilante is supposed to be somewhere around 3200-3400? RPM converter..... MY DS log on my car when it was only making 13 psi boost before I hardly added any bolt ons.... stalled to 3800 RPM @ 10 psi boost.

With that said.... take what someone says the stall rating is with a grain of salt.... because the same torque converter will stall differently behind 2 different engines..... or for that matter.... the same engine under two different boost levels. Another words..... the amount of stall is greatly affected by the amount of torque you put to the converter......

Clear as mud?

 

[87GNcospg]

just curious how long it "should" take me to see any boost on the boost gauge while stalling it. with the stock converter it took a few seconds.

 

[Blazer406]

What exhaust housing do you have? .... IMHO you don't have enough converter probably.... so it will take longer. If you have a PTE .85 exhaust housing...... it is really going to take some time to build boost with that housing...and converter.....

 

[XLR8]

Did you say you could spool the -63E with the stock D5? IF not, I bet that you do not have enough stall with a big shaft turbo and you being at over 6000'. Drive down to Pueblo and see if it spools at 4900'. If so, you need a looser converter.
With a D5 I couldn't spool my -44 at Bandimere but I could at PMI in Pueblo.

 

[87GNcospg]

if people only knew how hard we have it at a 1 mile+ altitude
i could spool my te44 with the stock converter. i could get about 5 psi in colorado springs. never launched hard at PMI.

 

[corsair231]

Turbos are load sensitive. Their boost is not directly related to rpm. If you were building boost with that turbo and the stock converter but not with the new one then you may have a too loose/bad converter. You said it went to 3400 with out building boost. If you still have slippage in your converter at 3400 then you don't have enough load on the engine and it won't build boost (like reving the engine in park). Like Blazer406 said converters vary from application to application and you may just need to stand on it until it stalls out. Once you do, assuming everthing is correct, ie: wastegate setting, proper fueling, no leaks, etc., then your boost will probably come on strong and fast.

 

[Blazer406]

I would mash on it til it started to build boost.....unless it went over 4500 RPM or something.... then I would definately look at converter problems.....

Let me clarify this a little.... If you mash on it and it starts building RPM slowly and then starts to build boost slowly.... and say 5 sec..... 8 sec... roll by and it is still stalling and building boost..... I would be aware.... that the tranny during this time is building a tremendous amount of heat.... very very very (did I mention very) fast. This heat can and will destroy your tranny if you keep mashing on it letting the converter slip under a large load.

With that said.... don't hold the brakes... mash on it.... and it just goes up to 4000 or so RPM and starts to build boost .... say 20 seconds roll by .... cause your tranny might not live.....

Just thought I would clarify.