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1994 Eldorado
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Discussion Starter #1
Hey Guys, I just got my hands on a 1994 eldo with 146k on it. It is the ld8 motor and runs like a dream! My question with these is, is it worth hotrodding this motor? That wasn't my intention, but after I drove it around I realized the perfect combination of power and style with these beauties.

My concern is that I'm reading about frequent head gasket issues and the fact that they really can't be rebuit like say a small block chevy. I'm about to do a tune up, and before I got started I figured I would reach out for some sage advice.

Is it worth putting upgraded wires, coil packs, ignition, etc. as well as are these motors responsive to headers, exhaust, intake? I've read about a few people adding a 100hp shot of nos for fun, but I don't want to invest in this motor if I'm destined for trouble. In that case I'll keep it a daily driver and move on to another project.

Am I better off replacing ignition components with oem parts, and trust in GM engineering, I know these computers are sensitive and don't want to waste my time, or shorten the life.

Any advice or if anyone has squeezed some more power I would love to hear it.

Thanks

Anthony
 

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2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
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:welcome:

acarew said:
My concern is that I'm reading about frequent head gasket issues
Head gasket issues aren't common as a whole. They are somewhat common on cars that are for sale.

and the fact that they really can't be rebuit like say a small block chevy.
They can absolutely be rebuilt.

I'm about to do a tune up, and before I got started I figured I would reach out for some sage advice.
A "tuneup" on a Northstar is a plug and wire change at 100K (using ONLY the correct AC Delco plugs). What were you planning on having done.

Is it worth putting upgraded wires, coil packs, ignition, etc. as well as are these motors responsive to headers, exhaust, intake?
There is virtually NO after market support for these cars, so none if those parts exist. A free flowing, custom exhaust will get you ~1-2 HP at WOT, at redline. Your car already has a cold air intake from the factory, that can flow more air than the engine will ever need.

I've read about a few people adding a 100hp shot of nos for fun, but I don't want to invest in this motor if I'm destined for trouble.
The risks to your engine and transmission are the same as running NOS on any other unmodified vehicle.

In that case I'll keep it a daily driver and move on to another project.
Your Eldo has 270 HP, 300FT/LBS of torque, and that's what you're stuck with.

Am I better off replacing ignition components with oem parts
In almost all cases, OEM parts are highly recommended. There are a few exceptions.

Any advice or if anyone has squeezed some more power I would love to hear it.
Have a spare $16K?:
http://www.youtube.com/watch?v=CTwc8N-sjw4
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Re: 1994 eldorado hotrodding

Yep ............ You have what you bought. (Just about the same boat for ALL of us FWD Seville/Deville/Eldorado drivers.) Dammit.

The factory CAI is already good, "performance" MAF's are not, no way for headers, ignition is very, very, very tightly controlled by the ECM.

BUT, for you, there may be a few hp in the clouds - Talk to Lyndon Wester of Wester's Garage, Canada. If you know exactly what you want to change and modify, they can do some magic on your OBD1 ECM (we have PCM's) and get you a tad more fuel mileage and maybe a hp or two.

Kicker is, with your LD8 (VIN Y) drivetrain and its 3.11:1 economy/highway final drive you're already crippled, and it's not just a matter of difficult intake cam swaps, either.
 

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1994 Eldorado
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Discussion Starter #4
Re: 1994 eldorado hotrodding

Thanks for the reply. For the tuneup I was looking at larger, low resistance wires (msd 8.5mm) and msd blaster coil packs/ ignition. Ac delco plugs, and cooling system flush. I read adding the bars leak pellets is reccomended? I always thought that stuff can wreak havok? Sounds like hp vs $ on exhaust isnt worth it then.

As far as cams go, I figured as such with "dohc" and 32 valves I didnt think there was much to be done.

Guess she will just be a nice daily cruiser, that is still fun to get on the highway.

Thanks again
 

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2001 Seville STS, 1990 Seville (RIP), 1972 Sedan Deville
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You won't get anything out of ignition mods.

A cooling system flush isn't necessary, unless you're trying to flush a stop leak product out of the system. All you need is a drain and fill, once every 2 years, 3 years max.

The coolant tabs are no longer used or recommended by GM. They tend to clog small coolant passages.
 

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Re: 1994 eldorado hotrodding

Yes, MSD (and maybe ACCEL) make coils and wires for the early Northstar. Net gain: bling only. Bragging rights, no power.

The absolute best "ignition mod' for your car is a squeaky clean coil pack and ICM, as well as perfect electrical connectors to/from the ICM to the crank and cam position sensors (timing triggers).

Google "waste spark ignition" to get a handle on what you're dealing with. MAKE SURE the new AC Delco ??? plug wires are connected to the correct coil and plug. AC Delco Platginum plugs only. www.rockauto.com

IF you know a GOOD exhaust shop and want to spend ??? $750 ??? on a mandrel-bent system, cat back, that will make some noise and give you a hp or two out at WOT redline.
 

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Submariner409 said:
Kicker is, with your LD8 (VIN Y) drivetrain and its 3.11:1 economy/highway final drive you're already crippled, and it's not just a matter of difficult intake cam swaps, either.
Oops, thought I read ETC. Inedited my post.
 

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1994 Eldorado
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Discussion Starter #8
Re: 1994 eldorado hotrodding

Good to know, so I dont waste money on "sticker horsepower". Last thing, I dont have it in front of me, but I was getting a p035 code. I believe it was "low voltage to pcm" any common issues with this? I figure check for corrosion and make sure battery wires are tight. Then check continuity and grounds to the pcm? It is located below the airbox correct?
 

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Re: 1994 eldorado hotrodding

Not sure - but for some handy info and instant gratification, subscribe the car to www.alldatadiy.com. The GM service manuals plus so much other info you need a home study course to find it all.
 

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1994 Eldorado
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Discussion Starter #10
Has anyone used "bg 44k" on the N*? I know the oil additives can actually destroy these motors, but was wondering about fuel treatment. Not that I have any issues, but have always used the stuff and have a can laying around. Again though im quickly learning that additives arnt well recieved by these. Basically, im looking to clean everything up since I have no idea how well she was cared for in the past.

Forgive the questions, im a small block chevy guy in a cadillac world now.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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DO NOT use any snake oil or fuel additives - except maybe Chevron TECHRON once in 5,000 miles - in a Northstar engine. The engines do not need it. (Chevy 327's - been there, done that - they can digest about anything; Northstars can't.)

Your flat tappet cam follower engine could benefit from a fleet/marine 10W-30 HD conventional oil with it's greater anti-scuff/anti-wear package. Your engine takes exactly 7.5 quarts of oil with filter to bring the level to the proper halfway mark on the dipstick hashmark.

Your transmission is a dry sump unit and there will be NO fluid on the stick with the engine off. Check fluid with the engine hot, idling in P on a level surface.

In its service manuals and owner's manuals GM is very specific when they say "Don't". The only advantage the "performance enhancing" additives is that they make the manufacturer's bottom line a little firmer, and in some cases the store counter person gets a spiff - kickback - for every bottle of stuff sold.

EDIT: Don't remember if I posted this - Google "chevron techron" and "top tier gasolines" for fuel system cleaning info.
 

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1994 Eldorado
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Discussion Starter #12
Conventional and not synthetic oil? Is that another N* quirk? Use the full 7.5 of that and not a mix eh? Good to know, im really thankful for you guys on here, saved me a lot of time, energy, and $ in just 1 morning.
 

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Your engine doesn't require Synthetic. And unless you drive the car very, VERY hard, or do lots if cold starts in VERY cold weather, there's really no benefit.
 

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1994 Eldorado
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Discussion Starter #14
Re: 1994 eldorado hotrodding

I ordered the 2 book factory repair manuals, in your opinion does alldata provide extra/better info? For $17 its probably worth it, but wanted some insight.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Alldata IS the GM manuals - in addition it offers troubleshooting and service tips, all Technical Service Bulletins, all recalls, labor times and rates, retail parts pricing (during the dates of the car's manufacture), updated RPO lists, other stuff......... but you'll need to surf the site for your car to find out where to find it all.

A few CF members use the parts diagrams and line drawings in maintenance/repair replies in these forums.
 

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1994 Eldorado
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Discussion Starter #16
Alright, so plugs, oil, pcv, air filter all taken care of. The negative battery cable was loose so im guessing that was the problem with the pcm. Now, maybe I should stop doing my own repairs and maintenance because for the life of me I dont see a coolant overflow tank? I was going to drain and fill, but all I see is the rad cap? Unless thats just the type of system gm used? If so, approx how much fluid will it take after I pull a hose and drain the radiator. Or if there is a smarter way to change the coolant im all ears. Thanks guys!
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
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Alright, so plugs, oil, pcv, air filter all taken care of. The negative battery cable was loose so im guessing that was the problem with the pcm. Now, maybe I should stop doing my own repairs and maintenance because for the life of me I dont see a coolant overflow tank? I was going to drain and fill, but all I see is the rad cap? Unless thats just the type of system gm used? If so, approx how much fluid will it take after I pull a hose and drain the radiator. Or if there is a smarter way to change the coolant im all ears. Thanks guys!
-------------------------
or you could wait a couple more days
until the Service Manuals get there
and do a little browsing through them -
 

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1994 Eldorado
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Discussion Starter #18
Could wait... but only a small window when im off of work and the landlord is away so I dont get hasseled! I hate not haveing a garage, makes things much more chalenging. Was that your way of telling me to calm down, read a little more, and find its a closed system? Plus im currently driving my bosses car until I have this ready to be a daily driver!
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
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Could wait... but only a small window when im off of work and the landlord is away so I dont get hasseled! I hate not haveing a garage, makes things much more chalenging. Was that your way of telling me to calm down, read a little more, and find its a closed system? Plus im currently driving my bosses car until I have this ready to be a daily driver!
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Was that your way of telling me to calm down,
read a little more, and find its a closed system?

YES -

Plus im currently driving my bosses car
until I have this ready to be a daily driver!

nice boss!

you are dealing with a 19 year old Cadillac -
with almost 150,000 miles on it -

it's probably going to need a little TLC -

be sure to check each and every heater hose -
and there are quite a few -
pay particular attention to the curved and 90* elbows -
feel each outside edge - the hoses should be firm - but flexible -
if any of them feel soft - or spongy -
they need to be replaced - immediately -
a simple popped hose WILL leave you stranded on the side of the road -

check out those belts - any sign of cracking - replace them -

other common - and overlooked weak points -
check out the belt tensioners and pulleys - also the idler pulleys -

if the waterpump tensioner or idler pulley seizes -
it quite often destroys the plastic cam driven pulley -

there is just a lot of stuff that needs to be checked out before
you can depend on it as your Daily Driver -

oh - I wouldn't recommend hot-rodding ANY 19 year old car -
with 150K miles on it - whether a Cadillac or a SB Chevy -
 

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1994 Eldorado
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Discussion Starter #20
Dually noted, there will be no hotrodding here. I figured hoses and belts on my next oportunity, im sure it wouldnt he all that expensive to just replace them myself. Like you said all it takes is one hose to end up stranded and im looking at a 30 mi. Each way commute. The advice is much appreciated and, I've been driving his car for 2 months, I guess another week or 2 isnt going to be an issue.

Reading as much as I can about these, I still cannot find the fluid capacity for the cooling system, I.e. how much coolant/water solution to add after I drain it. In the past I would run it and add to the overfloe was fluid got sucked into the system.
 
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