L67 GXP build (update: 9/16/13)

[00Beast]

Does the GXP use the same V5 compressor the 3800 does?

EDIT: Answered my own question: No, it doesn't. Add A/C compressor, lines, dryer and filter to your list of parts that need to be replaced, as well as a re-charge.

[nos4blood70]

Can't contribute much mechanically to this thread, so I'll let the big boys do their thing.
Just wanna wish you good luck though! I can't wait to see it take shape.

[redzmonte]

Here's a big difference: The GXP doesn't have a resonator

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Andrew, more points to confirm/consider (just throwing things out there):

The A/C setup in your pics next to the fusebox. Is that a difference or are the parts just different colours?

from my experience on swaps here is how i would answer your questions..

What about vacuum hose routing? Will there be any leftovers once you gut the engine bay? they will be replaced or removed with the engine removal.. may have a couple lines that need hooked up but noting major, most everythin is on the motor itself

Cruise? should work fine, will most likly need to swap cruse control cable along with throttle cable
Steering component locations (rack, lines)? rack will be fine, will most likely need hoses for a L67 car because of the PS pump placement

Brake line routing downstream of the master cylinder? unless i dont understand something it should not need to be touched
EBCM location? ecu will get replaced with engine/haness. BCM should not need to be touched

Would you have potential issues on 4T65-E outputs for HUD compared to those from the 4T80? Or does it pull from the WSS at each wheel? the HUD reads from the ECU, when you change the ECU the HUD sees the changes. should not be issues there

As for the weight difference, the N* is a HUGE engine, alluminum or not it is MASSIVE... Block, Heads (32v) and Cam towers are heavy. and you are correct on the trans there is a good weight savinigs there going from a 4T80-E to a 4T65-E HD. i would have guessed more then 170lbs but never checked. should feel better ballanced after the swap, not so much front bias/understeer.

[00Beast]

The EBCM is the Electronic Brake Control Module. I'd guess it's the same as the SSEi, or the SSEi parts will work with it.

[harofreak00]

The car has been sitting for a long time! Now that we have some decent weather I've finally started working on it.

Earlier this week, I pulled the drivetrain out.


Sorry, no pics of this stuff, but it is happening!

I removed the exhaust system, and installed my old SSEi exhaust with the Corvette tips, Magnaflow cat and Pacesetter collector on it.

I removed the old fuel lines and replaced them with my old SSEi so I didn't have to mess with changing the quick connects.

I installed the subframe and PS rack from my SSEi. I installed new struts and swapped the FE5 springs onto them.

I installed all new pads and rotors and cleaned up the calipers real good.

Now to begin work on prepping the engine and trans for some major work. I'm going to be putting a polished GenV on it, with a cam & intercooler. Lots of work ahead.

[SSEiMan01]

Definitely looking forward to this build!

[ga93sle]

Looks like fun! I'm excited that it's getting going!

[myfirstbonnie]

Excited to see the end result of this.

[repinS]

I installed new struts and swapped the FE5 springs onto them.

FE5 struts or aftermarket?

I've always wondered if aftermarket units can keep up with the extra stiffness of the FE5 spring.

[harofreak00]

The Monroe quickstruts that I had on my 00. The original struts had 144k on them, and were SUPER rusty, not worthy of this build.

[WhiteArrow3800]

Polished GenV, with a cam & intercooler.

[yourgrandma]

Ill have to cut up a monroe strut to test on a shock dyno, but I can almost promis you the monroe struts for bonnevilles are all the same, from park aves to gxp, they're all fluff. Id seriously consider new replacement delcos or grand prix gxp bilstiens.

[Sadden]

Those bilstiens are nice......
).)
(.(

[BonneMe]

Ill have to cut up a monroe strut to test on a shock dyno, but I can almost promis you the monroe struts for bonnevilles are all the same, from park aves to gxp, they're all fluff. Id seriously consider new replacement delcos or grand prix gxp bilstiens.

This. The differences between Fe1 and F41 never blew me away either... Any H body I've ridden in has been under-dampened.

[nos4blood70]

Any H body I've ridden in has been under-dampened.

This.

The ride quality seems to change more than handling characteristics between FE1, FE2, and F41. They're all boats.

[yourgrandma]

I did some serious digging at one point on all the different struts that will fit our cars. The front was reasonably easy. Like I said, the Bilstiens *should* fit and would obviously be the nicest choice. The Delco replacements for the GXP can be has for a reasonable price and are actually valved differently.

Ive brainstormed the underdamping issue many times. One alternative solution that is sometimes used in some classes of circle track racing is to drill a hole in the shock or strut and drain the oil. Refill with heavier shock oil and put a spot weld on the hole. The results can be unpredictable, especially if you dont know the original oil weight.

One thing is certain, an overdamped car feels better than underdamped. I never could figure out why the soggy ride quality has persisted so long in domestic cars.

[harofreak00]

How it sits...pre-cleaned

[SSEiMan01]

Cool to see she's making progress!

[myfirstbonnie]

So does this mean we need to add another section to the forum for the 2004-2005 GXP L67's?

Looking good Andrew. Keep the pics coming.

[SSEiMan01]

So does this mean we need to add another section to the forum for the 2004-2005 GXP L67's?

More general. "Frankenstein 3800 Cars."

More examples of cars that could be included in that forum, S2 L67 87-91 Bonnevilles, L67 Swapped LeSabres, and Cammed L26 Dust-Buster Vans.