Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Milled heads and stock intake problems

Thread Tools
 
Search this Thread
 
Old Nov 22, 2015 | 05:24 PM
  #1  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default Milled heads and stock intake problems

Any simple solutions? My heads are milled .040 and I'm getting a misfire from cylinder 1. The more I torque the intake there the better it gets. So, unless there is a better idea, I'm going to pull the intake and just RTV the new gaskets that are already on the truck and throw it back on. It is that close to sealing so I'm confident it would be a permanent solution.
Reply
Old Nov 22, 2015 | 05:43 PM
  #2  
jblankenship's Avatar
TECH Enthusiast
iTrader: (5)
 
Joined: May 2012
Posts: 626
Likes: 1
From: Mechanicsville, VA
Default

mill the intake
Reply
Old Nov 22, 2015 | 06:25 PM
  #3  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

That's time with the truck down and more money. I will if I have no choice but I hear of slotting the bolt holes and removing the bottom of the sleeve on the bolts works.
Reply
Old Nov 23, 2015 | 05:21 PM
  #4  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

Tried to RTV the intake gaskets and it didn't do anything but make it worse.

Open for input.
Reply
Old Nov 24, 2015 | 03:42 AM
  #5  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

Still no solid solution.
Reply
Old Nov 24, 2015 | 07:42 AM
  #6  
Full-Force's Avatar
TECH Junkie
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (11)
 
Joined: Aug 2004
Posts: 3,070
Likes: 5
From: Upstate of SC
Default

Im not sure what answer you are hoping to find. You have milled the heads and now they dont align with the intake. Maybe a thicker head gasket, but you aren't going to make up an extra .040. The intake is gonna have to be milled IMO. Otherwise find you some cheap stock heads just to get it back on the road.

Now when you say you rtv'ed the gaskets....did you put intake on with rtv wet? You could try again and put a thick neat bead around the ports on the head and let it sit until it firms up but not dry that way when it compresses it doesnt squeeze it all out.
Reply
Old Nov 24, 2015 | 07:42 AM
  #7  
tug686spd's Avatar
TECH Resident
15 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (11)
 
Joined: Mar 2008
Posts: 800
Likes: 16
Default

Any chance its not a intake leak? Maybe a partialy clogged injector from junk that may have accumulated at end of fuel rail and during disassembly/reassembly found its way there. Maybe a broke injector wire since it seamed to get better after you torqued the intake again at first, you could have wiggled the wires while trying to get down on the bolts.
Reply
Old Nov 24, 2015 | 10:01 AM
  #8  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

Have played with the wires, swapped the injector, swapped the coil as well. Process of elimination has been pretty good so far.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Nov 24, 2015 | 10:02 AM
  #9  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

Originally Posted by Full-Force
Im not sure what answer you are hoping to find. You have milled the heads and now they dont align with the intake. Maybe a thicker head gasket, but you aren't going to make up an extra .040. The intake is gonna have to be milled IMO. Otherwise find you some cheap stock heads just to get it back on the road.

Now when you say you rtv'ed the gaskets....did you put intake on with rtv wet? You could try again and put a thick neat bead around the ports on the head and let it sit until it firms up but not dry that way when it compresses it doesnt squeeze it all out.
Just open to suggestions, that's for sure.

Makes me wonder if the thinner gasket will help. I may put the stock gaskets back on. Couldn't hurt.
Reply
Old Nov 24, 2015 | 10:52 AM
  #10  
98cherrySS's Avatar
TECH Resident
15 Year Member
iTrader: (2)
 
Joined: Jun 2008
Posts: 802
Likes: 59
Default

I milled .075 off my heads. I shaved the dowels on the LS6 intake and it sealed just fine.
Reply
Old Nov 24, 2015 | 12:15 PM
  #11  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

That's just it, these truck intakes don't have that. I hear of no issues that far and then there are guys like me with barely no sealing.
Reply
Old Nov 24, 2015 | 12:41 PM
  #12  
jimmyblue's Avatar
Moderator
iTrader: (11)
 
Joined: Mar 2002
Posts: 12,604
Likes: 7
From: East Central Florida
Default

Maybe cut a gasket to make up the shaved height
and put between the heads & intake? And goop down
the side that mates to the heads?

Another thought - for my PP intake I had to go to button
head valley cover bolts because the underside interfered
with the stock ones. Maybe shaving the heads has brought
stock truck manifold similarly into interference, maybe
little enough that you don't notice until trying to get seal?
Reply
Old Nov 24, 2015 | 02:32 PM
  #13  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

I was looking at that under side of the intake in canes that was the issue but the under side is huge and goes way up. No real way for the caller bolts to hit anywhere. Would have been nice.

Hopefully my buddy will be here in a bit and we will get back off in the truck and see what we can figure out.
Reply
Old Nov 24, 2015 | 06:51 PM
  #14  
ZONES89RS's Avatar
Thread Starter
In-Zane Moderator
15 Year Member
iTrader: (25)
 
Joined: Jan 2007
Posts: 11,941
Likes: 33
From: Conroe, Texas
Default

Thank you guys for the help. As it turns out, I totally forgot the truck acted like **** the night before pulling the intake for repair. Literally right before parking it. Next day, a limp to the other house and RTV the intake gaskets and bam. Problem was solved but knock sensors screwed up the timing table. Near zero misfires today after my buddy/tuner hooked up to the ECM. Only one was reading 2-4 and that's normal.

So far so good and the truck GT it's final WOT tune. Only thing left is a HD2 shift kit to help the 187k mile trans out.
Reply




All times are GMT -5. The time now is 11:42 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE