5.7 Vortec MPFI Conversion issue, PLENUM WONT GO ON!

[aggiecowgirl12]

Howdy,

So I have the new spider in properly, I have the upper plenum back in place, however I can't get it to seat properly. It's as if the new spider is up too high? Has anyone else come across this issue? I have some reservations about just tightening the plenum bolts in the zig-zag pattern, obviously because if I strip out any of the threads, I'm screwed. I've pressed down on the plenum with as much equal pressure as I can muster, but it doesnt seem to do any good. Just wondering if anyone has any ideas before I end up breaking something.... I'm a pretty decent mechanic, but obviously I'm out of ideas... Thanks

Oh, I have a 97 k2500 with the vortec 5.7l v8.... 4x4 NV4500

And I run ONLY AMSOIL products...


Semper Fi, Do Or Die.

[1.721afr]

Howdy,

So I have the new spider in properly, I have the upper plenum back in place, however I can't get it to seat properly. It's as if the new spider is up too high? Has anyone else come across this issue? I have some reservations about just tightening the plenum bolts in the zig-zag pattern, obviously because if I strip out any of the threads, I'm screwed. I've pressed down on the plenum with as much equal pressure as I can muster, but it doesnt seem to do any good. Just wondering if anyone has any ideas before I end up breaking something.... I'm a pretty decent mechanic, but obviously I'm out of ideas... Thanks

Oh, I have a 97 k2500 with the vortec 5.7l v8.... 4x4 NV4500

And I run ONLY AMSOIL products...


Semper Fi, Do Or Die.

I think it can have something to do with the spider routing getting in the way, they only fit right one way?

[shamrock246]

Which mounting bracket did you use?


Sean

97 4x4 burb

[aggiecowgirl12]

Well, the diagram shows you how to wire it, so I based it off of the diagram and how to best fit them under the plenum.

I tried BOTH mounting brackets, the new and the old, and they both seem to stick up too far... the only thing I can think of, is to tighten it down as much as I can, with the proper zig-zag pattern for the plenum and see if it maybe seats correctly...


any more ideas?

[Jon4x4]

Cut the mounting bracket down

[aggiecowgirl12]

Thanks to those of you who legit knew what I was talking about

I got the plenum down, by throwing some petroleum jelly around the o ring and the side of the spider assembly... then I started tightening the plenum bolts down in the correct pattern, and eventually it settled in nicely...

By the way, the performance difference is noticeable... I mean its a big ass 3/4 ton long bed truck, with an NV4500, so its not ment to be a speed demon, but it runs Much better now... I dont hear the pinging, or stalling, and it seems much happier :)

Now if I can only get the damn AC figured out...

Semper Fi, Do Or Die

[kencoc]

As the poppets get old, putting the MPFI on is a big differance. I had the same problem get mine back together. I used oil, just a little a first then realized it needed more to slide all the way in.

[Sidewaysthe7]

I'm needing to do the same thing on my '96 Suburban because I think I'm having some issues and at 248K+ I'm sure that I'm long overdue. Which kit did you use to upgrade?

[shamrock246]

this is the one i used for my 97

http://www.amazon.com/Delphi-FJ10566-Fuel-Injector/dp/B000TYLIFS/ref=au_pf_ss_1?ie=UTF8&Model=K1500%20Suburban%7C455&n=15684181&s=automotive&Make=Chevrolet%7C47&Year=1997%7C1997&carId=001

Sean

97 4x4 burb

[Paul2281]

I had the same problem with mine after changing out the FPR....The dang old upper plenum would sit in right until I lubed up the oring and tightened it down SLOWLY,lol....

[silverado_lover]

Howdy ag :D

[JokerZ71]

changed mine to the BWD spider @ 475,000 miles.Mine was smoking,smelling like gas,& gettin bout 9 mpg.LOL.Since i drive 100 miles a day,i had to do somethin quik. luckily.i had no problems.Mine settled in just fine & ran alot better> It made a big difference as far as pep,idling & even upped my milage to 18 mpg.It never got more than 16 when the truck was new.

[sphillips]

I
I had the same problem with mine after changing out the FPR....The dang old upper plenum would sit in right until I lubed up the oring and tightened it down SLOWLY,lol....


Ditto on this