Author Topic: 87 k10 350 tbi tuning?  (Read 7446 times)

Offline buzzman351

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Re: 87 k10 350 tbi tuning?
« Reply #15 on: October 11, 2022, 06:03:09 AM »
i probably should add that my original TBI was toast so i bought one from a guy that was on a 94 chevrolet. i had to wire a different TPS connector but everything else hooked up as it should

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #16 on: February 14, 2023, 04:59:24 PM »
Finally replaced the O2 sensor, definitely made a difference in that the feathering action takes it to a higher RPM.

Still won't idle

Smells rich

Since I had B+ disco'd there are no codes, so will have to do the feather dance till some get thrown.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #17 on: February 15, 2023, 05:40:56 PM »
Smells rich, won't idle, did you disconnect the vacuum hose at the EGR valve?
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #18 on: February 15, 2023, 07:45:29 PM »
Not that I'm aware of, will check tomorrow. Thx!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #19 on: February 16, 2023, 03:52:34 PM »
I am suggesting that you do to see if it is hanging open.
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #20 on: February 17, 2023, 02:40:20 PM »
Got it, thanks!

I looked yesterday, there is a electronic module between it and the source.

1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #21 on: February 17, 2023, 07:09:16 PM »
Just pull the hose off of the EGR valve and let it dangle in the wind. See if it affects the way it runs.
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              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #22 on: February 22, 2023, 03:59:59 PM »
VZ

It definitely changed the way it behaves, tried to idle, I can now feather it to much higher RPMs.

Looks like it's stuck? Any thing else to add?

Thanks buddy!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #23 on: February 22, 2023, 06:09:23 PM »
You should have no vacuum at the hose to the EGR valve with the engine running. If you do, replace the EGR solenoid.
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                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Online bd

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Re: 87 k10 350 tbi tuning?
« Reply #24 on: February 23, 2023, 09:31:34 AM »
In addition to vacuum bleeding past a faulty EGR solenoid, an EGR valve is susceptible to carbon accumulation that can prevent seating of its pintle allowing exhaust to bypass the valve.  To check the EGR valve for bypassing, remove it from the manifold and flip it upside-down.  The pintle and seat are inside the short steel tube protruding from the base of the valve.  Dribble some penetrant (e.g., carb cleaner or penetrating oil) into the open end of the tube without disturbing the valve diaphragm.  If the penetrant leaks past the pintle and seat into the underlying chamber, the valve is bypassing and should be replaced.  A valve in good condition will not bypass at all.  Be sure to install a new gasket.

Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #25 on: February 23, 2023, 01:03:21 PM »
Thanks guy, I'm on it!!!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #26 on: March 13, 2023, 03:50:54 PM »
Finally got the EGR off, with the help of a box end 1/2 inch wrench with a curious 115 degree bend. Custom made with the help of my torch...

Doing the leak down test now.

I can blow air through the module from either of the tubes. Just curious if when power is applied a valve closes.

Napa lists the module as an "Eichlin air filter".  ???
« Last Edit: March 13, 2023, 10:59:53 PM by JohnnyPopper »
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #27 on: March 13, 2023, 11:00:47 PM »
Leak down failed.

Ordered parts, will keep you posted. THANKS!!!!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #28 on: March 14, 2023, 06:21:30 PM »
There's a small foam filter on the solenoid. I'm not sure exactly what you are working on since this thread says 87 k10 (which is a V10) and you mentioned an R30?
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #29 on: March 15, 2023, 09:03:09 PM »
Yeah sorry, I hijacked a 87 K10 thread with my own silly problems...

It's a '88 1 ton w/454/400 TBI.

Their is a filter on the solenoid.

Q: when the solenoid is energized is there a valve that forced closed?

In the absence of 12v, I am able to blow through either port. 

Just wondering if I need a new solenoid.

Thanks!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction