Jump to content

LQ1 intake swap


Nas Escobar

Recommended Posts

So I've been having issues with my LIM in which the water seeps out from an edge when it gets cold outside and usually stops when the engine is heated up. I've changed the gasket 2 times already and it seems the gasket lasts the same amount as I change the gasket in January or February (usually) and starts seeping water around November or December. This would  be my 3rd time changing it. Incidentally this is my 3rd year owning this car as well.

 

With that being said, I was going to change the LIM and UIM/Plenum as the plenum does have a rounded thread near the serpentine side and I believe the LIM to have an uneven surface as I bought the car with a leaking LIM (leaked air not water however) and it has never lasted a year.

 

Now here is where things get funny. I have found a 97 Z34 at the junkyard complete, only thing missing is the air box. I was contemplating picking up the complete intake but wasn't sure if it interchanges. I know 96 and 97 had a detached throttle body and the coils were on the side of the intake instead of the bottom which interests me (as I believe the heat of the exhaust manifold is messing with my coils). However as I did research, I've come to find that I need more than just the intakes and that for some this is considered a "power mod" as it would give me larger intake ports. So with that being said, has anyone taken a 96/97 intake port and swapped it onto a 94/95 engine?

 

I ask because I would like to know what was done with the EGR, what exactly needs to be taken out of the Z34 and what do I need to do to my 94 Cutlass to get this to work properly.

 

All help is appreciated.

Link to comment
Share on other sites

So I've been having issues with my LIM in which the water seeps out from an edge when it gets cold outside and usually stops when the engine is heated up. I've changed the gasket 2 times already and it seems the gasket lasts the same amount as I change the gasket in January or February (usually) and starts seeping water around November or December. This would  be my 3rd time changing it. Incidentally this is my 3rd year owning this car as well.

 

With that being said, I was going to change the LIM and UIM/Plenum as the plenum does have a rounded thread near the serpentine side and I believe the LIM to have an uneven surface as I bought the car with a leaking LIM (leaked air not water however) and it has never lasted a year.

 

Now here is where things get funny. I have found a 97 Z34 at the junkyard complete, only thing missing is the air box. I was contemplating picking up the complete intake but wasn't sure if it interchanges. I know 96 and 97 had a detached throttle body and the coils were on the side of the intake instead of the bottom which interests me (as I believe the heat of the exhaust manifold is messing with my coils). However as I did research, I've come to find that I need more than just the intakes and that for some this is considered a "power mod" as it would give me larger intake ports. So with that being said, has anyone taken a 96/97 intake port and swapped it onto a 94/95 engine?

 

I ask because I would like to know what was done with the EGR, what exactly needs to be taken out of the Z34 and what do I need to do to my 94 Cutlass to get this to work properly.

 

All help is appreciated.

You may have already seen this...

 

http://60degreev6.com/content.php/69-96-97-3-4-DDOHC-Intake-Manifold-Swap-for-91-95-Engines

 

I had a similar problem with my Cutlass. When I did the last intake gasket replacement, I polished both surfaces with a cloth cone mounted in a drill...no polishing compound, just the cloth cone. I haven't had a leak in the 5 years since.

Link to comment
Share on other sites

That's the exact link I was looking for, I found Crunk Munky's thread and that thread link was dead on that.

 

So it is true that it makes more power gains huh? See that makes me want to do it more, it's just the EGR valve thing that worries me since last time I tried taking the tube off, it broke on me, luckily this was on a 95 Monte Carlo at the yard and not my 94.

 

I have read the EGR has different wiring connectors however. How true is this and how many people have actually done this on the site?

 

Perhaps I should ask this on 60degV6?

 

 

I might take your advice however if I decide not to do this. I eventually want to run 2.50 exhaust pipe on my Cutlass to 2 Borla mufflers and quad tip it so I am considering the intake for a slight bump in power overall.

Link to comment
Share on other sites

Just be sure to go ahead and replace at least the rear spark plugs...once you put the newer intake and plenum on your car, the plenum has to be removed on '96-up to gain access to the plugs.

Link to comment
Share on other sites

It doesn't have the notches as the 91-95 did? I didn't check out the stuff real close I was running out of time at the yard.

Link to comment
Share on other sites

So with that being said, has anyone taken a 96/97 intake port and swapped it onto a 94/95 engine?

 

The later design cyl heads are a different casting than the older heads, the intake & exhaust ports are not the same, the intake manifold gaskets are also not the same so one would not be able to swap intake assemblies back & forth between the two designs, too bad GM didn't get this right the 1st time as the later intake breathes better than the old.

Link to comment
Share on other sites

I have everything to swap mine whenever I end up getting around to it, although the vacuum lines were all messed up so I was gonna run all new hoses. To my recollection the gaskets definitely need to be 96/7, as well as basically anything above that. Take pictures and do a decent write up so I'm motivated to do mine

Link to comment
Share on other sites

The later design cyl heads are a different casting than the older heads, the intake & exhaust ports are not the same, the intake manifold gaskets are also not the same so one would not be able to swap intake assemblies back & forth between the two designs, too bad GM didn't get this right the 1st time as the later intake breathes better than the old.

The definitely can be swapped, but there are some quirks. I had a bunch of links bookmarked a while back, I'll see if I have them still later

Link to comment
Share on other sites

^ If you can find that article I'd be interested as well, was offered a later 96 engine some time back, thought about this change but after looking at the two engines decided against it after noting the gasket differences, the later lower intake/thermostat housing design, the EGR differences, all of what has to be altered for the sake of approx. 6hp....but I'd still like to read on the subject.

Link to comment
Share on other sites

^ If you can find that article I'd be interested as well, was offered a later 96 engine some time back, thought about this change but after looking at the two engines decided against it after noting the gasket differences, the later lower intake/thermostat housing design, the EGR differences, all of what has to be altered for the sake of approx. 6hp....but I'd still like to read on the subject.

I'll dig it up, but it's been done a number of times. It's a bit of a chore (and the 96/97 engines are a lot more rare), so it's not a super common thing to do

Link to comment
Share on other sites

EGR is certainly different between the two.... 91-95 use the 3 solenoid digital setup while 96/97 uses the linear EGR style found on all GM stuff 96+(and a few earlier than that).

 

you would need to make/find a physical adapter to put the digital setup on the newer manifold and have the original PCM control it or block it off and change the calibration to match or move to the newer PCM. I'm putting together a 4th option now for the 93-95 3100 PCM that could more or less apply to the 94-95 LQ1(and even 91-93) PCM that equates to some internal modifications to the PCM to allow for the increased current the linear EGR causes along with some code change to make sense of all of it. in theory, one could just tie all of the EGR outputs together and have the capability of 4 channels worth of quad-driver current-sinking capability(around .75 amps/channel, for a max of 3 amps compared to the roughly ~2 the solenoid should draw) and have the code control all 4 channels at once, but I have other plans for those outputs.

Link to comment
Share on other sites

I have everything to swap mine whenever I end up getting around to it, although the vacuum lines were all messed up so I was gonna run all new hoses. To my recollection the gaskets definitely need to be 96/7, as well as basically anything above that. Take pictures and do a decent write up so I'm motivated to do mine

 

Yes, that is correct, looked it  up sadly only made in fucking plastic. Who the fuck still uses fucking plastic gaskets? The 3800 folks got their upgrade to metal. The 3400 folks got their gaskets updated too. Why did the LQ1 get stuck with those shitty nylon gaskets that do nothing but fail? WHAT THE FUCK FELPRO????

 

 

Anyways, I guess a pic of everything I need would help that way I know what I'm getting into and I would do a write up.

 

EGR is certainly different between the two.... 91-95 use the 3 solenoid digital setup while 96/97 uses the linear EGR style found on all GM stuff 96+(and a few earlier than that).

 

you would need to make/find a physical adapter to put the digital setup on the newer manifold and have the original PCM control it or block it off and change the calibration to match or move to the newer PCM. I'm putting together a 4th option now for the 93-95 3100 PCM that could more or less apply to the 94-95 LQ1(and even 91-93) PCM that equates to some internal modifications to the PCM to allow for the increased current the linear EGR causes along with some code change to make sense of all of it. in theory, one could just tie all of the EGR outputs together and have the capability of 4 channels worth of quad-driver current-sinking capability(around .75 amps/channel, for a max of 3 amps compared to the roughly ~2 the solenoid should draw) and have the code control all 4 channels at once, but I have other plans for those outputs.

 

Now converting to OBD2 sounds like a pain in the ass... and while it would let me use a normal scanner instead of TunerPro, I rather stay stuck in OBD1.5.

 

I was thinking I would have to hack up the tube to make it longer and get it to fit where the intake is but now idk. See this is why I haven't taken a day off work and gone to pick up the 97 stuff. I need the EGR for emissions, won't pass without one, they do a visual check.

Link to comment
Share on other sites

you may be able to take a route that I haven't seen mentioned in a long time(though I'm not certain why): the EGR "base" adapter used on the 90-94 3.1MPFI engines can somehow be used to attach the digital solenoid setup to a 96-99 or 00+ 3x00 intake(I think it's 96-99). considering how much GM loves to reuse stuff, I would take some pictures/measurements the next time you find something like that and you may have a ~$5 EGR adapter for the LQ1.

Link to comment
Share on other sites

hmmm, this is good to know, as if I can I'd almost rather have the EGR functional, but i figured when I did mine the easiest would be to disable it and block of the egr with a plate that I bought that I have no idea where it ended up :lol:

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...