North American Turbocoupe Organization



Wastgate riddle
Turbofry Offline
Member
#1
Question about the wastegate. Say a certain mechanic while putting on the new T3 turbo bent the actuator rod connecting to the wastegate. Could this bent rod cause the wastegate to stick open? If so, would the cause effect be more gas dumped in than air and flood out? What would be the effects of having a stuck open wastegate?

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88TC - KN filter, Motorsports A233 cam, adjustable cam gear, 3" exhaust W/ 3" downpipe. Gillis boost valve, Hurst short shifter, 3:73 rear, T3, 155lph fuel pump, 60mm Mustang throttle body. Sub-frame connectors. Port matched and polished head. Gutted upper and lower intakes. Saab 900s FMIC.
88TC - KN filter, Motorsports A233 cam, adjustable cam gear, 3" exhaust W/ 3" downpipe. Gillis boost valve, Hurst short shifter, 3:73 rear, T3, 155lph fuel pump, 60mm Mustang throttle body. Sub-frame connectors. Port matched and polished head. Gutted upper and lower intakes. Saab 900s FMIC.
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Noname
Unregistered
#2
It takes a LOT of effort to bend a 1/4" thick peice of steel, so unless he used the wastegate actuator arm as a jacking location, I wouldn't think it would be bent. Even if it were bent, that would actually shorten the rod's effective length and thereby keep the wastegate closed with even more pressure.

I don't have any idea what you mean by "more gas dumped in than air and flood out". Fuel delivery is primarily controlled via input from the VAM (in addition to rpm, air temp, barometric pressure).

If your wastegate WERE stuck open, boost would take forever to build because less exhaust energy is being forced around the exhaust wheel and is instead escaping out the wastegate prematurely.

Just out of curiousity, what kind of problem are you having with your car? If you explain it to us, we might be able to help you narrow it down a bit.

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Estoril blue 1987 TC 5spd, 136k miles
k&n cone in fenderwell, PRofec B electronic boost controller, kirban adjustable fpr set at 44psi base, walbro 255 hi-pressure pump, Bailey BOV, ported e6, stock IC, a237 cam, mildly ported head, t3/t4 50 trim / stage III .63, full 3" exhaust, eec-tuner, 55pph injectors, dave compton a/f meter, Nitto 555R drag radials
Best 1/4 mile (before tuner, turbo, injectors, drag radials): 14.120 (with 1.983 60' time)
Best trap speed: 98.44mph
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Turbofry Offline
Member
#3
The problem I am having is that the car runs fine building up boost but when it goes to actual boost the car bogs down and sputters. I can barely get 1 lb of boost before this happens. The mechanic actually bent the actuator rod to go around the oil feed line from the block to the turbo. The turbo spools up fine but bogs down when trying to boost. There is a slight exhaust leak where the downpipe meets the exhaust housing. Everything seems to be connected, the check engine light doesn't come on. I was leaning towards the wastegate or fuel pressure but I am not sure.
88TC - KN filter, Motorsports A233 cam, adjustable cam gear, 3" exhaust W/ 3" downpipe. Gillis boost valve, Hurst short shifter, 3:73 rear, T3, 155lph fuel pump, 60mm Mustang throttle body. Sub-frame connectors. Port matched and polished head. Gutted upper and lower intakes. Saab 900s FMIC.
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Glenn 88TC Offline
Posting Freak
#4
Check your fuel pressure. You can never do that enough. When is the last time you bought wires? Does it run and boost fine when you don't give it full throttle?

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Glenn 88TC
current mods: ported & polished big valve head(1.89/1.59), ranger roller, custom upper and ported lower intakes, t3/t4 turbo, powerstroke intercooler mounted full size, 60mm throttle body, R.C. Engineering 42lb. injectors, MSD 6al, MSD Launch Control, MSD 8.5mm wires, K&N filter, Walboro 255HP pump, Kirban adj. fuel reg., ATR header, full 3" exhaust with Dynomax Ultraflow muffler, Star stage III clutch, Hallman boost controller, Flex-a-lite adj. temp switch for stock fans, Weld Draglites with M/T ET Street 26x11.5/15

87 Merkur Xr4ti - daily driver
NO TC and NO headaches.
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Turbofry Offline
Member
#5
The cars good until boost tries to kick in, either under slight throttle or fool throttle. I do want to check the fuel pressure. What should the pressure be under boost?
88TC - KN filter, Motorsports A233 cam, adjustable cam gear, 3" exhaust W/ 3" downpipe. Gillis boost valve, Hurst short shifter, 3:73 rear, T3, 155lph fuel pump, 60mm Mustang throttle body. Sub-frame connectors. Port matched and polished head. Gutted upper and lower intakes. Saab 900s FMIC.
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Hybridbird Offline
Posting Freak
#6
Around 40 PSI base,then add 1 pound of fuel for every pound of boost.
idle=40 psi
5 psi boost=45 psi
10 psi boost=50 psi
and so on.

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Too much fun, what's that mean?That's like too much boost,there's no such thing.
"Finch....get the f*ck away from that Ficus......that's a jizz-free Ficus!"
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