It is currently Fri Mar 29, 2024 4:58 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 5 posts ] 
Author Message
PostPosted: Wed Jan 17, 2018 2:33 am 
Offline
SLE Member
SLE Member

Joined: Thu Sep 10, 2015 9:02 pm
Posts: 62
Year and Trim: 2000 SE. 2000 SSEi, 2001 SSEi, 2002 SLE
Anyone ever consider a 5.3 swap in the GXP? I just dont understand why the grand prix got the LS and the much cooler Bonneville was stuck with a boat anchor


Top
 Profile  
 
PostPosted: Wed Jan 17, 2018 12:37 pm 
Offline
Certified Bonneville Nut
Certified Bonneville Nut
User avatar

Joined: Wed May 13, 2009 10:45 pm
Posts: 5827
Location: CHICAGO
Year and Trim: 2006 STS-V, 2004 GTO, 2009 G8 GT
We've had this discussion at least once before in here, but I can't seem to find the thread...

It boils down to two factors;

1) Cost. This car shares it's platform with Cadillac's (STS's) of the same vintage. They use Northstars. Why expend the cost to re-engineer something that you only will sell a small percentage of when you already have that engineering amortized and paid off? Remember the GXP was only a 2 year model run that you were killing off the platform it was on, as a whole, after 2005 anyway.

2) The Bonneville GXP came before the Grand Prix/Impala SS/Monte Carlo SS. Matter of fact, the Bonneville was dead (2005) before GM even brought out the Grand Prix GXP/Impala SS/Monte Carlo SS with the LS4 (2006 - 2009), which at the time was a quick band-aid, "stop gap" solution to counter the Chrysler LX cars.

And the grass isn't greener. As much as I prefer a GenIII+ motor personally, the 5.3 LS4 used in the Grand Prix GXP, Impala SS and Monte Carlo SS, once you get past D.O.D. which has oil consumption issues, you have the weaker 4T65E transmission behind it. To help save it, they dial up a ton of torque management and TCC slip on initial engagement. So you basically swap out engine issues for transmission issues...

_________________
Image

Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*

Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ

Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck


Top
 Profile  
 
PostPosted: Wed Jan 17, 2018 4:01 pm 
Offline
Certified Bonneville Nut
Certified Bonneville Nut
User avatar

Joined: Mon May 10, 2010 6:11 pm
Posts: 9491
Location: Chicago, IL
Year and Trim: 2003 SLE
I don't see what you're improving... It's still a V8 stuck in a front wheel drive cage one way or another.

_________________
-Car Guy Carl
"Penelope" - 2003 SLE - 247k Miles
"Sydney" - 2000 Honda S2000 - 98k miles
Image


Top
 Profile  
 
PostPosted: Fri Jan 19, 2018 8:38 pm 
Offline
Posts like an LN3
Posts like an LN3
User avatar

Joined: Thu May 22, 2008 3:53 pm
Posts: 573
Location: Nashville, TN
Year and Trim: 82 GP
You've gotta really love the Bonneville to want to go through with it I'd think.

Best scenario would be to keep the 4t80e and swap motors, and then just work out the kinks with controlling the trans. Looks like there are people with LS4 w-body's though who've swapped to the 4t80e though so it's not entirely new territory.

_________________
Image

2009 Chevy Silverado 2500HD crew cab, 6.0, Z71. The project mover.
2002 Regal GS: 3.4 pulley, E85, and quicker than my old 99
1982 Pontiac Grand Prix L67, T56, GT45, T56, Holley EFI; It's pretty quick Mod list here


Top
 Profile  
 
PostPosted: Fri Apr 13, 2018 11:14 am 
Offline
Posts like an L27
Posts like an L27
User avatar

Joined: Sat Dec 25, 2010 1:16 pm
Posts: 698
Location: Virginia
Year and Trim: 2004 SLE
For much less money you can rebuild the Northstar with top and bottom stud kits and make a very reliable engine. That doesn't resolve other issues with the car but it does keep the better trans and little to no mods needed. Previous reading here also showed that fixing the weak front motor mount also helps fix the leaking trans fluid lines by not over-flexing them.

If you love the Bonneville, the Northstar can be improved and not suffer the oil problems of the LS4. That would be my choice if I had one of these cars.

_________________
2004 Bonneville SLE "Bonnie the Ghosthawk" or the 4dr Firebird...Gone but not forgotten
Image

The Blog, http://www.tobthebat.wordpress.com

Luna LeMans on Smashwords
https://www.smashwords.com/books/view/870754

Luna LeMans in Amazon paperback
https://www.amazon.com/dp/1983273589


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 5 hours [ DST ]


Related topics
 Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Another Crazy Idea (LS4 Swap?)

[ Go to pageGo to page: 1, 2 ]

04BlackGXP

24

4581

Tue Apr 23, 2013 8:18 pm

CMNTMXR57 View the latest post

There are no new unread posts for this topic. 3800 to northstar swap on 95 se

soundman9826

3

1897

Thu Feb 15, 2018 12:36 pm

CMNTMXR57 View the latest post

There are no new unread posts for this topic. Project 2005 GXP: HOW-TO: Northstar Engine Swap

94SilverSSEi

2

5375

Fri Jul 28, 2017 11:06 pm

CMNTMXR57 View the latest post

 


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group


phpBB SEO