Rocker/Springs question.

[Sabrewings]

L67 springs are the same as L36 springs. If you're gonna go 1.9s you should upgrade to 105# or L76 springs.

 

[Brammer]

L67 springs are the same as L36 springs. If you're gonna go 1.9s you should upgrade to 105# or L76 springs.

:th_thumbsup-wink: I meant to say L76. My bad.

 

[Bio248]

im not saying that ER rockers wont work, but will they be the best for a blown setup? probably not. you need more top end breathing which 1.9s would get you.

 

[Brammer]

So I've been doing my reading for the top swap and I'm gonna plan to do it by July. I'm fairly confident about everything except the pulleys/harmonic balancers. Where do all these go what pulleys get replaced? I was wondering if any of you happen to have a picture showing the location of these. Also what type of PCM would I need to get from Intense, would just one for a GTP work or do I need to specify to them that it is for a top swap? Also would it be advised to change the valves while I have the heads out?

Also, I'm a little confused on this part :
"Run a vacuum line to the fuel pressure regulator and the MAP. The fuel pressure regulator needs to see boost in order to operate correctly. Go ahead and attach the Boost Bypass Valve to the supercharger. It's held on with a bracket and two bolts. Run a vac line from the tree on the supercharger to the top nipple on the BBV. The bottom one needs to see ATMOSPHERE, because our L36 PCM's cannot control the BBV."

Where is this vacuum line that will go to the FPR and the MAP at on my car now? and what are they going to now? Basically a bunch of pictures would be awesome.


Edit : Dumb question is there any way to make the boost gauge on DIC work after this swap?

 

[Bio248]

you need a couple more idlers and a tensioner. you get one idler and the tensioner from the l67 coil pack bracket. you get another idler from a cone looking piece. you then have to replace the balancer with the l67 one so you have two sets of ribs. then you need the heads and up from the l67, the fuel rails, the MAP sensor, throttle body, etc.

the BBV is something youd understand once you got the setup nearly complete. the l36 PCM doesnt know how to control the BBV so you have to just leave it open to the atmosphere on the bottom of the solenoid and that will allow you to get full boost. you will no longer be able to dump boost on torque management, traction controls, etc.

people have done the DIC, but i just opted for a real boost gauge since that one is inaccurate and it only reads like 6 pounds of boost.


overall a top swap isnt a TON of work, but if you dont know your way around this car and motor youre going to learn a lot. you can basically follow the write up for a cam swap and it is pretty much the same thing with a few more odds and ends.

 

[Brammer]

Well I'm fairly confident with the removal of the LIM, heads, rockers etc. My worries come to the fuel rails (my last car caught fire keep in mind, but it was due to battery hitting the hood) I'm also very picky I've pretty much decided to buy L67 heads and replace the rockers, valve springs and push rods and have a valve job done before it gets installed. So the BBV comes with the S/C correct? What do you mean by this "you will no longer be able to dump boost on torque management, traction controls, etc."?

And also any word about those vacuum lines? And this idler with the cone looking piece is this listed in the parts list for the top swap write up? Any write ups of how to make the DIC show boost?(I like it for the looks)

 

[Bio248]

if youre going that far i would get some headwork done and run a nice cam.

the BBV comes with the blower. what i mean that you cant dump boost is that the stock l67 will limit boost to about 4 pounds when torque management and traction control kick in. it should be listed in the write up, that is a complete parts list.

im not sure how your vacuum lines are hooked up. i dont remember how mine were before i did the swap. it was so long ago. my vacuum lines goes from the rear of the blower to the front. it goes MAP > LIM > FPR.

 

[Brammer]

if youre going that far i would get some headwork done and run a nice cam.

the BBV comes with the blower. what i mean that you cant dump boost is that the stock l67 will limit boost to about 4 pounds when torque management and traction control kick in. it should be listed in the write up, that is a complete parts list.

im not sure how your vacuum lines are hooked up. i dont remember how mine were before i did the swap. it was so long ago. my vacuum lines goes from the rear of the blower to the front. it goes MAP > LIM > FPR.

I don't really plan on pushing the car that far to need that much. I more or less just want a fun DD. However while you're answering questions lol. Should I bother replacing my valves if they aren't bent?

Also I can't find what you're referring to about the torque mgmt. and traction in the write up? Can you pinpoint it for me or briefly explain it to me?

 

[Bio248]

i wouldnt replace the valves if they are still good. it is the valve guides and seats that would be messed up if anything.

it isnt in the write up about that stuff. normally a GTP will limit boost under certain conditions using the BBV. because the l36 PCM cannot control the BBV, you can no longer expect the motor to do that so you have to tune knowing that it wont do that. you have to make shifts faster/stiffer so you dont burn your clutches under boost, etc, etc.

it just means that you wont dump boost under certain conditions, which is a bad thing if you allow torque management to do it's thing. torque management will pull fuel. no fuel + high boost = blown motor. you have to deal with the torque management while youre tuning, that is what im getting at.

 

[Sabrewings]

I just did this. I'll answer what I can.

So I've been doing my reading for the top swap and I'm gonna plan to do it by July. I'm fairly confident about everything except the pulleys/harmonic balancers. Where do all these go what pulleys get replaced? I was wondering if any of you happen to have a picture showing the location of these.

Never mind the red circle, but this is the pulley routing. For a top swap you need to get swap the harmonic balancer for a L67 balancer. Then you add the smooth idler, the SC belt tensioner, and the ribbed idler is mounted on the L67 coil pack bracket. Your current belt routing for the accessory belt stays the same.

Also what type of PCM would I need to get from Intense, would just one for a GTP work or do I need to specify to them that it is for a top swap?

An in car tune is best. You can get a mail order tune if they know how to tune for a top swap. The higher compression ratio of the L36 bottom end will make it more prone to knock.

Also would it be advised to change the valves while I have the heads out?

Not unless it's needed.

Also, I'm a little confused on this part :
"Run a vacuum line to the fuel pressure regulator and the MAP. The fuel pressure regulator needs to see boost in order to operate correctly. Go ahead and attach the Boost Bypass Valve to the supercharger. It's held on with a bracket and two bolts. Run a vac line from the tree on the supercharger to the top nipple on the BBV. The bottom one needs to see ATMOSPHERE, because our L36 PCM's cannot control the BBV."

Where is this vacuum line that will go to the FPR and the MAP at on my car now? and what are they going to now?

The line you need is not on the car now. You would need to pic up the L67 vacuum line. The one on your car goes from the TB to the FPR and the EVAP solenoid. It will not be reused on a top swapped engine. The line to the EVAP will probably need to be reused, but you need to use the L67 vacuum line so that the FPR and MAP will see boost. Your current MAP doesn't have a vacuum line since it's already mounted on the L36 UIM.

Edit : Dumb question is there any way to make the boost gauge on DIC work after this swap?

I don't have a GP, but on Impalas all you have to do is swap to a cluster with a boost gauge and run a L67 file on your PCM. Might not be that easy on GPs. I just got a real boost gauge.

Well I'm fairly confident with the removal of the LIM, heads, rockers etc. My worries come to the fuel rails (my last car caught fire keep in mind, but it was due to battery hitting the hood)

As long as you get a L67 fuel rail it isn't a problem.

I'm also very picky I've pretty much decided to buy L67 heads and replace the rockers, valve springs and push rods and have a valve job done before it gets installed.

How can you replace the pushrods when they're in your engine? Pushrods are not part of the head. Also there's no need to replace them unless they're damaged. They don't really wear.

So the BBV comes with the S/C correct? What do you mean by this "you will no longer be able to dump boost on torque management, traction controls, etc."?

Yes, the BBV is the black cylinder on the side of the SC case. Without a boost bypass solenoid (different from a BBV) the PCM won't be able to dump boost when it wants to (like torque management and traction control). It isn't really necessary unless you drive your car like a douche.

And also any word about those vacuum lines? And this idler with the cone looking piece is this listed in the parts list for the top swap write up?

Vacuum lines see above. I don't think I have any pictures to show you. You're best bet is to pop the hood on a L67 car and look around.

I'm not sure which idler you're talking about, but it has to be the tower idler.

Should I bother replacing my valves if they aren't bent?

No. But you should still take the heads to a machine shop to have them reconditioned and checked for cracks. Here's a thread to pictures from when I had my heads reconditioned:

http://www.grandprixforums.net/f18/reconditioned-heads-10753.html

Also I can't find what you're referring to about the torque mgmt. and traction in the write up? Can you pinpoint it for me or briefly explain it to me?

What's hard to understand about torque management and traction control? On a stock SC car the PCM bleeds boost while torque management is active or traction control is active. Without the solenoid it can't do this.

Here is the thread showing my tear down and rebuild. Tear down took one day, rebuild took three. There's so many little parts that are different between the two engines you have to be prepared. I researched for over a year and collected parts over six months before I did it. All that and I got held up by little stuff like not having the right coil pack bolts. You literally tear it down to the block and replace everything. Hardly anything is reused.

http://www.grandprixforums.net/f18/official-joining-you-post-13626.html

You will also want to make sure you have it tuned or run a larger than stock pulley. Stock programming will knock pretty bad on a top swapped car. You will also want breathing mods to help it stay together.

Let me know what other questions you have. My main advice is research it and go over it part by part until you know exactly what you're doing step by step. The devil is in the details.

 

[blueguy]

Holy crosseyed post batman...that one was HUGE

Like he said...IMO if I was doing a top swap I would find a GTP motor for sale in good condition and buy then then just pull crap off of it whenever you run across something you need...

 

[Brammer]

Thanks for the very informative post Sabre. So do I have to remove a solenoid to make the TQ mgmt and Traction not bleed boost? Also do you happen to know if Intense tunes for a top swap or any other mfg. for that matter? I know that tuning myself is best, but I just don't have the extra money for the tuning software, let alone a laptop.

 

[Sabrewings]

Thanks for the very informative post Sabre. So do I have to remove a solenoid to make the TQ mgmt and Traction not bleed boost?

That's the easiest way. You'll need to find a way to plug the empty spot on the vacuum line if it is removed. No need to plug the bottom of the BBV as it can stay open to atmosphere and work as designed. I just never got one so I didn't have to worry about it.

I used the empty spot on the vacuum line to feed my boost gauge sender. Works fine.

Also do you happen to know if Intense tunes for a top swap or any other mfg. for that matter?

Not sure. The closest to it would be ZZP's SSM90 kit programming, but then you'd have to have a ZZP PCM.

I know that tuning myself is best, but I just don't have the extra money for the tuning software, let alone a laptop.

I would consider being able to tune it part of being prepared. You're frankensteining together two different engines in a way that GM never had in mind. It's going to take some tweaking to run right.

Oh, something that came to mind while discussing the BBV solenoid. You'll need an adapter for your MAP sensor so you can use a L67 MAP sensor. The connectors are different. ZZP sells a L67 swap kit that comes with a MAP adapter and wiring for a BBV solenoid if you really want to add one. I bought it early on in the "parts" portion of my preparations. I used the MAP adapter but never ended up using the BBV solenoid wiring since I have no BBV solenoid.

 

[Brammer]

I'm afraid I'm a little lost now.....

Where is this solenoid I'd need to remove? and what would be the negatives to removing it?


So if I don't get the MAP adapter for the BBV solenoid what will that change? If I do get the solenoid and wiring what will that change?


I'm confused....

 

[Brammer]

This Basically this is what I need right?

Or This?


I guess what I'm most confused about is :

If I just swap over all the parts and don't remove any solenoids what will happen?
How do I fix said problem?
How do I fix said problem correctly lol?
What does that fix require buying/adding?

 

[Scimmia]

I'm afraid I'm a little lost now.....

Where is this solenoid I'd need to remove? and what would be the negatives to removing it?


So if I don't get the MAP adapter for the BBV solenoid what will that change? If I do get the solenoid and wiring what will that change?


I'm confused....

Ok, I'm going to lay out the BBV system really quick. There are 3 parts to it, the valve, which is in the supercharger housing, the actuator, which is the black canister on the front of the supercharger, and the solenoid, which is bolted to the actuator. The valve is a butterfly valve which leads from the lower intake back to the inlet of the supercharger. It's there so that the boost can be bled off when it's not needed, like while just cruising down the road. The valve is controlled by the actuator, which is vacuum operated. The top of the actuator is connected to vacuum before the supercharger, and the bottom is generally open to atmosphere. As vacuum increases (lower throttle), the plunger is pulled up, which opens the bypass valve. The solenoid is there for computer control. It's connected to the outlet side of the supercharger and to the lower part of the actuator. When the computer sees that you're running boost and it doesn't want you to, it can use the solenoid to feed the pressure into the bottom of the actuator, forcing the bbv open and bleeding off the boost. Removing the solenoid just removes the computer's ability to bleed off boost when it wants to, like during shifts or when the traction control comes on.

You need the L67 MAP for the computer to be able to tell when you're in boost, and you need an L67 computer to be able to read the L67 MAP correctly and control the BBV solenoid. If you don't care about the computer controlling the solenoid, you don't need an L67 MAP or computer, you can just tune your L36 computer.

 

[Sabrewings]

Where is this solenoid I'd need to remove? and what would be the negatives to removing it?

You don't have one now. And you don't have to remove it... It just makes things easier.

So if I don't get the MAP adapter for the BBV solenoid what will that change? If I do get the solenoid and wiring what will that change?

The MAP adapter is for the MAP. The BBV solenoid wiring is for the BBV solenoid. Not having the wiring and solenoid means the PCM can't bleed boost if it wants to. Simple as that.

Seems to me you need to locate a good service manual and read up how the supercharged engine works. You're messing with a lot of stuff it doesn't seem you quite grasp yet.

 

[Brammer]

Thanks Scimmia,

So what happens if I don't remove the solenoid? Will it not boost correctly? Basically what Sabre was saying is that where the Solenoid vacuum line WAS after removing it I could run to a boost gauge, correct?


Sabre, essentially just remove the BBV solenoid and I won't need the BBV wiring kit and it's good right?

 

[Brammer]

Wait a minute after re-reading I think the big picture is coming in now.

If I use my L36 computer and tune it for the swap I will want to remove the BBV Solenoid and won't need an L67 MAP sensor or the wiring harness for it.

However, if I use an L67 computer tuned for the swap I can retain the BBV Solenoid, WILL need the L67 MAP and MAP harness.

Is this what we're aiming for?

 

[Scimmia]

Bingo, you've got it. There are actually people that remove the solenoid even with an L67 computer, they don't want the computer screwing with their boost.