Engine/Transmission (1994 - 1998) #8 boost question

[Jdimig]

hey all



ive had the #8 plate for a while now and just love it. recently i sild it all the way forward and messed around with the screw on the boost elbow( closed the screw) and max boost im seeing is about 27psi. this seems right with the plate, but i wanted a little more air, so i disconnected my waste gate and the boost number didn't change. so my question is do i have possible boost leak, or is that all the air im gonaa get with my current setup, even with the wastegate blocked? i just got my 16cm2 housing so that will be on in the next couple of weeks, but still curious about why im not seeing more boost with the wastegate blocked. thanks in advance for any input!



-wes

 

[bmoeller]

Your boost sounds low with the wastegate disabled. I can peg my 30# boost gauge with my #10 in the stock position, if I want.

 

[Andy Redmond]

I would say that you are about right. You might have a pump set on the low side. Pressurize the charge air system and look for leaks, maybe the inner cooler has sprung a leak.



You may notice a couple of psi less of total boost with the 16cm2, but you should develop more power once it spools up and comes on.



Good luck

Andy

 

[Jdimig]

thanks for the input guys. im gonaa do a pressure check this weekend and see what i get. i just may go retighten everything and see if that helps. also i forgot to add i have a good amount of smoke at full throttle, and that leads me to think that i need a little bit more air, and will get rid of that smoke, but hey we all love smoke

 

[Andy Redmond]

Good luck, let us know what you find. FYIW most plates will make some black smoke at WOT, just let off ever so slightly and it should change to light gray.



I responded to a post recently and I explained where I found a leak at the charge air cooler core/unit.



Andy

 

[JGheen]

Man, how can he only be getting 27# of boost with the #8 plate and I am getting 38-40# with my #10 plate? I understand he may have a boost leak but I have seen others with lower number plates that get those mid to high 20s boost numbers, but why? I don't have my wastegate pinched either just what's in the sig.

 

[Andy Redmond]

I'm guessing because he has a "911" 180hp auto trans truck, Wes' tag doesn't say, with the exception of what I think may be a hint ... "mag-hytech dd tp. "



If so this is a mild uprate vs quite a bit more like your #10 in the 215 pump. If this is the case, then the #8 would really be more of an "animal" in your 913/215hp truck. However, as we discussed in the past it takes some tuning to get plate other than #10,4 and 0's to work well w/gov. springs.



I see boost levels he describes with this combo frequently (especially w/out gov. springs).



Andy

 

[JGheen]

Tuning with plates other than #10, 4 and 0, you mean, messing with the governor lever to get it to ride the other profiles of the other plates, right?

Also, the "913" you refered to are the injectors, right? I have never really known what they call the stock injectors in a 215 HP engine. If so, why do they call them 913s?

 

[blacksheepdiesel]

My friend's '95 3500 w/160 pump and auto was built with #8 plate, 4kgsk's, 370's, and wastegate disabled. It will build 38 psi at will with the plate slid back.



Trent

 

[JGheen]

Originally posted by redbadge

My friend's '95 3500 w/160 pump and auto was built with #8 plate, 4kgsk's, 370's, and wastegate disabled. It will build 38 psi at will with the plate slid back.



Trent

What turbo was that combo run with?

 

[bmoeller]

The 913 is refering to the fuel injection pump. The OEM injectors with your truck are 215s.

 

[blacksheepdiesel]

JGheen,



Stock as far as we know, never have looked it over to be honest.



Trent

 

[Jdimig]

still stumped

well i got under the hood tonight and discoverd that some of the clamps "seemed" loose, so i tightend all of them up as best as i could, and visually looked at the rubber elbows to see if they were perhaps cut or damaged at all and didn't see anything. so i took her for a test drive(of course it started to rain) and really didnt see that much change in boost. im going to hopefully get my 16cm2 housing on this weekend and see if that helps at all. i know im going to loose some boost, but ill be able to elminate the possiblity of a problem with my waste gate. if im missing anything here chime in guys. thanks for all the help.



-wes

 

[bmoeller]

If you have access to an air compressor, get a gauge and a regulator to test the wastegate diaphram for a leak and opening pressure. Also check the diaphram in the AFC housing for leaks.



Check the line going to the AFC housing to see if it is pinched or damaged. If it is, it will limit fuel delivery.

 

[Jdimig]

thanks bmoeller ill try that. im also wondering if the waste gate could be stuck open possilby? i guess i would be loosing alot more boost if it were