Luke

92 Seville 4.9 - interesting mods in progress

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This is my 92 Seville. Yes, it is a Seville and not an STS. I bought all STS body panels and bumpers from a salvage, painted them, and installed. It has been my daily driver for about a year and a half. I recently changed jobs and needed to drive 35 miles each way for 3 months of training.  I was getting about 17 mpg so, I bought a 2017 Jaguar XF 20d. 42 mpg. BUT, that doesn’t mean I am getting rid of my Cadillacs. I have 5. The Seville has been very slowly losing coolant for a year or more. I’ve tested for head gasket leaks several times and nothing. Time for intake gaskets. 
 

Anyone who has been around long enough to remember “the guru”, may remember talk about some factory test cars with the 4.9 that had some interesting modifications. There were quite a few back then who wanted to try this but to my knowledge, it was never done. Photo of the project in comments. 

EDCF2778-96CE-43F3-AD3C-1665699023B7.jpeg

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Intake manifold......odd but your picture seems to show the Allante version intake. My '93 4.9L Seville did not have that style intake.  

alanteintake.JPG

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You got it. I’m putting the entire Allante intake manifold on my 92 Seville. Here is a before photo. 

8977EF60-5CD2-43C5-9B03-6B0B7549D4A6.jpeg

Edited by Luke

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I am enjoying this. Don't see many Sevilles. 


GM FAN FOREVER

Nice, clean, luxury= fine automobile

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I’ll keep posting updates.

Bruce, back in the day with your 92 STS, you got some pretty good gains with the chip, didn’t you?  I’ll likely get a chip for it once this is done. 

I’m not sure at the moment exactly how I am going to deal with the fuel rail. The Allante one has different hookups for the metal fuel lines. But with the Seville one, The fuel pressure regulator is in the way of the upper intake manifold. May have to figure out a way to bend it a bit without breaking it. 

I have to extend the wiring for the MAP sensor, ISC motor, maybe the IAT sensor but other than that, the wiring should pretty much reach. I have to put an Allante 124 amp early DS-144 alternator on. The Seville 140 amp DS-144 is too big for the space. I’m also not sure if I am going to keep the throttle body spacer that has coolant running through or not. But then again, if it helps the MPG  I mean, I have the 09 STS-V for when I wanna get into trouble. LOL 

This won’t be a long extended project. I’d like to have it done in a week or two. The pushrods tend to rust in the icky sticky Dallas air if out of the engine too long. Plus, when I bought this car, I got the leaky Freon hose repaired and kept it with R-12. Don’t want to let it sit too long and dry the refrigerant seals out. 

Today, I torqued the intake manifold bolts to factory spec. 8 lb/ft then 12 lb/ft. Then I reinstalled the distributor. Took photos so I knew exactly what position to put it in. 

384A48E8-2DCD-4464-B9DA-9CA0E6080B67.jpeg

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7 hours ago, Logan said:

Intake manifold......odd but your picture seems to show the Allante version intake. My '93 4.9L Seville did not have that style intake.  

 

Hey Logan, wasn’t your 93 Seville the one you painted the steering column for a steering wheel update? I’ve updated my steering wheel. Luckily, no paint was required. 

C69B4174-9A71-4D9A-B9DB-2D072FEBE415.jpeg

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Here was the mod page for my 1992 STS: http://www.caddyinfo.com/92sts.htm

Quote

PCM (Computer) - I installed a FastChip. Fastchip claims an increase at the flywheel to 220 HP, 310 ft-lbs of torque.  Easy to install - took 20 minutes. Ed Wright is easy to deal with

The Fastchip webpage is still there; possible they still have them


Bruce

2016 Cadillac ATS-V gray/black; 2013 Cadillac ATS 2L Turbo Premium (Wife's)

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19 hours ago, Bruce Nunnally said:

Here was the mod page for my 1992 STS: http://www.caddyinfo.com/92sts.htm

Definitely takes me back looking at that page. I was on here even back in the netgetgoing days. If I recall, my 1984 DeVille limo and 93 STS were on your people’s cars page. I think I’ve owned something like 16 Cadillacs since the.  Currently have the 92 Seville, 92 Allante, 08 DTS, 09 STS-V, and 1980 Seville limo. 

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3 hours ago, Luke said:

Definitely takes me back looking at that page. I was on here even back in the netgetgoing days. If I recall, my 1984 DeVille limo and 93 STS were on your people’s cars page. I think I’ve owned something like 16 Cadillacs since the.  Currently have the 92 Seville, 92 Allante, 08 DTS, 09 STS-V, and 1980 Seville limo. 

Certainly a nice set of Cadillacs.   Yes, I got the same nostalgic feel from that page.


Bruce

2016 Cadillac ATS-V gray/black; 2013 Cadillac ATS 2L Turbo Premium (Wife's)

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Making some progress! I put new spark plugs in and managed to destroy two of the spark plug wires in the process. Had to order new wires. Interestingly enough, the 4.9 uses the exact same plug wires as a Bentley Turbo R! Next step is to do some careful bending on the fuel rail so it can clear the upper manifold. After that, it’ll be time to route the vacuum lines and do the wiring. Some of the harnesses will have to be extended to allow for the new sensor locations. 

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Very nice. Show some pics of the car. 


GM FAN FOREVER

Nice, clean, luxury= fine automobile

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Allante intake manifold. The 4.5 and 4.9 are great motors . But, the inlet and outlet water pipes rust out that run underneath the engine and are no longer available.. It's a shame someone doesn't make those aftermarket! 

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Beautiful. Surely a one of a kind body style. Thank you for sharing. I kind of like yours better than mine. It has less clutter on the body. Mine has black and chrome trims

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GM FAN FOREVER

Nice, clean, luxury= fine automobile

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6 hours ago, rockfangd said:

Beautiful. Surely a one of a kind body style. Thank you for sharing. I kind of like yours better than mine. It has less clutter on the body. Mine has black and chrome trims

Here is a before photo of mine. It looked very similar to yours before I got all the STS body panels and front and rear bumper covers and grill and fog lights and put them on mine. I even painted them all myself to match the car. Had to come up with all the little out of production clips to attach them all. Mine is a base Seville. Still has digital cluster and column shifter but STS body. Oh, and yes, the bright red is the factory original paint. Rare 92-93 only color. And for some reason, all 92 Sevilles had black rear view mirrors  I painted them body color when I painted the panels and bumpers.

A4CB7556-96C0-4BB5-9E4E-17F3C654D00B.jpeg

Edited by Luke

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I knew those had to be STS parts. . Looks incredible.

I thought about making those changes to mine but it would cost more than I would want to spend to modify it. 

Mine is a tri coat, is yours? I realize we have 2 different Reds. 

Black mirrors... Thats strange.

It sucks I have a set of foglamps and switch for my Seville but it will not work because the Foglamp option was only on the STS. There is no place in the bumper for them. 

I did add them in my Deville and it was not a fun job. I stress these were not prewired at all for the option. I had to run all of the wires. They are completely factory and add a nice touch. The wiring goes from the headlight switch all the way to the trunk, from the trunk back to the headlight switch(for the ON indicator), then under the hood to the relay. Fuse and relay are also not prewired. I had to do that as well.

If you don't mind me asking what was involved with changing the cladding on the doors? 


GM FAN FOREVER

Nice, clean, luxury= fine automobile

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Very cool Luke, I'm enjoying watching this


Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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