Series III conversion - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat

Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

Thread Tools Search this Thread
Old 04-03-2009, 01:57 AM   #1
Junior Member
Thread Starter
Join Date: Nov 2008
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Coop_96_Bonneville is on a distinguished road
Cool Series III conversion

I've been brainstorming about the idea of taking a newer low mile Series III and swapping it in my 96 Bonneville SE, from what I understand the only major thing I would have to do is take the pig tails of the newer Series III fuel injectors and splice them into the Series II harness, swap the acces. brackets and sensors, maybe do some headers and cold air intake....

Anything else yall can think of that would have to be changed?
Coop_96_Bonneville is offline   Reply With Quote
Old 04-03-2009, 01:59 AM   #2
Retired Senior Admin

Expert Gearhead
Danthurs's Avatar
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Thanks: 0
Thanked 16 Times in 13 Posts
Danthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to all

I would say your PCM and wiring harness. Better change the transmission too.
Danthurs is offline   Reply With Quote
Old 04-03-2009, 09:19 AM   #3

Expert Gearhead
BillBoost37's Avatar
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light

The swap is a walk in the park overall. The motor uses the same block.

The fuel system is totally different though. You will need a Series 2 L67 (SC'd) fuel rail and injectors.

The throttle body on the S3 is drive by wire. You'll need a TB adapter and a throttle body. Depending on your future plans, I'd recommend either a stock L67 TB or a LS1/Northstar (2000+ Caddy 4.6 motor) with LQ4 (Chevy truck) maf.

Swap all your brackets onto it and lightly modifiy the evap vacuum routing.

Use either your exhaust manifolds or headers on for exhaust.

Change the oil filter adapter from a W body that heads for the passenger ide tire over to the H body that tucks under the oil pan. Might as well add an oil pressure increase kit while you have it apart.

Once you have it mostly done, you'll have a clearance issue with your alternator. You can clearnance the alt by shaving the back side of it slightly or swapping it to a different style. (Been there..done both). The different style requires a different connector...if you can solder well, it'll be seamless.

And then there is the consideration of your transmission. Currently your trans is the non-HD 4T60 transmission. This area is probably one where if you plan on modding (which it appears you will) that you need to consider many options. More on that later.

As for wiring, there'* no need to change your harness. You can add an extender for the MAP sensor and add the wiring for the boost control soleniod. Both Intense-Racing and ZZP sell a conversion kit.

PCM... You would proably want to source a 96 SSEi pcm. As for tuning the only options are or a DHP Powrtuner. This should also be considered in talking about the transmission.

Trans/PCM considerations. You have the non-HD 4T60 transmission. This is the wimply version of the vacuum controlled, heat producer transmission that in HD form is known for differential issues. It is relatively easy to move up to a 4T65HD transmission, the fully electronic, slightly beefier and cooler running transmission that became available in 97. Pretty much to do it, you swap the trans, add a different connector, add 5 wires to the pcm connector and change your pcm to a 97 SSEi. (You guessed it...I've done too much).

Holler if you would like some pics of things etc.
BillBoost37 is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Series II Intake Swap to a Series III Long block trickytransam Performance, Brainstorming & Tuning 9 03-23-2008 10:23 PM
Looking for photo of SC heads on Series II and Series III clm2112 Forced Induction 5 09-22-2006 10:53 PM
Series II, and Series III Merrill'spontiac General GM Chat 6 04-24-2006 07:52 PM
Series III UIM on a Series II? VigCS 1992-1999 10 01-12-2006 01:54 AM
Series II & Series III AD Bear Lounge 4 03-07-2004 08:14 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -4. The time now is 11:43 AM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.