Engine/Transmission (1994 - 1998) Delivery Valves

[NHays]

How can I tell if I have bad delivery valves, is there a diagnostic for them.

 

[bmoeller]

The only way you might be able to test them, would be to pull the pump and have it bench tested. Most likely, though, they are fine. Almost nothing to go wrong with them, unless someone put gas in the tank.

 

[Signal73]

anyones I pulled there is always a very tight tolerance between the valve and the holder. I dont know if there is a spec out there to tell if one was worn out?

 

[Matthug]

MY stock 131's with 250K on them appeared much more worn than the 181's I bought that had 130K on them.

 

[Signal73]

Yeah I recall if you didnt have them lined up dead nuts when sliding the D/V into the holder it would sorta bind up. If they wore down, would you get more fuel per injection?

 

[Matthug]

I can't really say accurately because when I installed my 181's my overflow valve went bad at the same time. I had less smoke and no noticeable power increase, but replaced the overflow valve and had noticeable increase in power but not so much smoke. Weird. My truck is really weird though, signal73 you will probably recall I was talking about the AFC light spring causing less responsiveness and slower spoolup. Well I just put the stock spring back in today and holy crap this thing is like a different truck it's a way better driving experience. Didn't mean to steal the thread or anything sorry.

 

[NHays]

No thats ok to steal this thread, my truck has Super B and #10 plate in stock position for now. But, the truck is kinda sluggish and getting only 14-16 mpg. whne it does eventually get boost it only maxes at 32 psi.

 

[Signal73]

I can't really say accurately because when I installed my 181's my overflow valve went bad at the same time. I had less smoke and no noticeable power increase, but replaced the overflow valve and had noticeable increase in power but not so much smoke. Weird. My truck is really weird though, signal73 you will probably recall I was talking about the AFC light spring causing less responsiveness and slower spoolup. Well I just put the stock spring back in today and holy crap this thing is like a different truck it's a way better driving experience. Didn't mean to steal the thread or anything sorry.

Man thats sumptin' Maybe too much low end fuel puttin out the fire so to say? I have low end smoke like crazy, hopefully the twins help to cure that...

 

[Matthug]

NHAYS- I doubt your DV's are worn out since you only have 144K on them. I would check your fuel pressure, sounds funny but low pressure can actually give you worse mileage. I was only getting 15-16 MPG, I changed out my overflow valve and get 17 now no other changes. I have a heavy right foot.

What do you have controlling boost? Sometimes the wastegate diaphram itself with a direct line on it makes exhaust vent too soon and cause low boost. You may need to get a boost elbow.

Signal73-I checked the springs out when I changed it. The light spring from TST is slightly less stiff than the stock one. The ''medium'' spring is 100% positively stiffer than my stocker. I think whats hurting is that even though the stocker is stiffer the TST spring it's 1/2'' longer and putting preload on the housing. If it was the same length as the stocker it would fuel sooner and harder. After I changed the AFC spring it fuels so fast now that I barked the turbo twice accidentally, never ever did that with the TST spring in.

 

[NHays]

I have a boost elbow. line is totally closed off to the diaphram and i have tightened the diaphram to WG connecting rod down. I know for a fact that the waste gate is not opening at all. I think i just need more fuel. but thats why i am putting this out there. whatcha think.

 

[Matthug]

Well for some reason the super B (which is a plain old S300G Schwitzer like the HTBG) comes with the 14cm housing... . same thing the sled puller 66 comes with! It should come with the 12 housing because the compressor doesn't really support such a larger turbine section.

32 PSI boost is all it may be producing, I don't believe the BD 10 plate is as aggressive as TST's. And the fact you are running 18* timing lowers overall peak boost. Thats a lot of timing for the HP you are producing, perhaps too much. Also the ATS manifold lowers boost. Yeah now that I think about it 32 PSI is probably fine, your sluggishness is probably the turbo as I described before. The most boost I could get with my setup with the 16cm non wastegated housing is 34 PSI. If I turned my timing up to 18 I have no doubt I would only get 30-32 PSI boost. Going from 12 to 15 lowered it from 36-37 to 34 PSI.

You need bigger injectors, that will spool the turbo a lot faster.

 

[zstroken]

Actually the HTBG is a slight upgrade from the s300 and I think you can get a 12 cm on the HTBG. Just a little better bearings in the HTBG, but Matthug is right the HTBG only has like 57 or 58 mm inducer if I remember right. Granted it is more effecient than the 60mm put on the HX40's.

 

[NHays]

sorry for got to change my sig, I backed the timing off to 15*, not sure how but I got it there, and the truck still runs. more low end, little quieter and less overall smoke, Now i need to bump the plate foreward a fuzz and see what that does. little higher boost and egts. 32-34.

 

[Matthug]

Actually the HTBG is a slight upgrade from the s300 and I think you can get a 12 cm on the HTBG. Just a little better bearings in the HTBG, but Matthug is right the HTBG only has like 57 or 58 mm inducer if I remember right. Granted it is more effecient than the 60mm put on the HX40's.

Didn't know about the bearings, but you can get a 12 on an HTBG for sure. I was just saying the super B version only came with the 14 but would be better with a 12 since it has a smaller 57mm inducer. Granted the extended tip technology helps but HTT's hot rod 40 puts out more CFM than their HTBG, it also supports 450 WHP whereas the HTBG will not. Oh you can get 450 HP with it easy thats all with fuel but it won't keep it cool. It actually keeps 475-500 cool but people have had reliability issues with over 450 WHP with any HX40. 500 HP spools it too fast and barks the turbo causing the shaft to break no matter how good you balanced it. And apparently the super 40 from holset puts out even more CFM but I trust HTT's balancing a lot more than holset's LOL.

My bro runs HTT's HX40 on his 02' ETH, it's a sweet turbo. With his TST comp box off he has 400 WHP, EGT's don't pass 1200 degree's empty no matter how hard you push it. He can only put his comp box up to level 5 (9 levels) because of clutch slippage issues, but he said he should be doing about 475 WHP with it on 5 and his EGT's topped at 1400 on a long hard WOT run up a steep 2 mile grade by my house. Took it all the way to the new redline of 3500 RPM compliments of the comp box in 6th gear. On a flat run it doesn't pass 1350. BTW he runs the LUK cerametalic, but he says the pressure plate feels less than stock. So he's planning on buying a 3400 PSI pressure plate and putting it in so it holds better, nothing wrong with the disc it's pretty good.