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supercharge my 98 lesabre


johnnybate
10-29-2004, 03:44 PM
im tentatively shopping around for an old eaton 3800 supercharger to install on my 98 lesabre custom.

what sort of difficulties would i run into with installing this?
can the frame handle it?
what about the differential?

anyones insight would be great

thanks,

johnnyb

avatar307
10-29-2004, 08:27 PM
Old supercharger + Car with whole bunch of wires. That'll make the EGR system happy. You'll probably set a bunch of engine trouble codes.

You'll also need to get a different crankshaft pulley and another idler arm for the second belt. At least, that's how the belts are installed on Buicks with a factory supercharged 3800s.

Beyond that, you'll likely have to move the alternater, power steering, and lord knows what else. The hood might not close.

Can the frame handle 20 more horsepower? Probably. Who knows. That's not really the point of doing it though.

There's some websites out there dedicated to racing cars with 3800-series engines... Pontiacs mostly I think.

Do front wheel drive cars have differentials?

pirho451
11-01-2004, 09:40 AM
What you'll need to do is buy an entire engine out of a Park Avenue or other model that had the 3800SC. The stock 3800's bottom end was not designed for the extra stress that the supercharger added, so GM strengthened it for the 3800SC. That plus you'll have to either get a wiring harness for a 3800SC equipped vehicle, or add the proper connectors to your existing wiring harness (assuming that can be done). You might also have to replace your ECM.

It's a big project, but one that can be done relatively easily if you've go the time and money. Everything else will be fine, as your car is almost identical, mechanically speaking, to the Park Avenue Ultra, which had the 3800SC stock.

If you have any other questions, you might want to check out the forums on www.l67swap.com. It's a whole website devoted to swapping the L67 3800SC engine into any number of cars.

avatar307
11-01-2004, 03:09 PM
I'd say it's almost an absolute certainty you would have to swap the PCM/ECM out of the car. The stock PCM would not be programed to monitor the extra variables created by the supercharger, and it would not be programed to correctly compensate for it. The engine likely wouldn't run, or if it did, it would run like crap.

The supercharger probably wouldn't even mount on the stock engine. At least not with removing half the components from the engine it was being taken from. I.e. The alternator will be in the wrong place, who knows if you can swap the brakets to move it to the correct location. Odds are the correct holes do not exist.

A full engine, transmission, PCM swap would be the only way to go. You may also have to swap the EGR, some of the vacuum components, the air intake, the radiator, and most likely the engine mounts. (As the supercharger will likely make the engine taller than the stock motor.)

Who knows if anyone makes kits with everything needed to do it. They might, as the L67 is a pretty popular engine. I don't know if it's popular enough for that though. Hell, I'm pretty sure K&N doesn't make any performance air setups for the engine, so that would be a good judge as to if others would also make engine mod kits.

johnnybate
11-01-2004, 04:30 PM
it almost seems like it would be an easier task to look into a turbo solution?

any thoughts?

avatar307
11-01-2004, 08:30 PM
Adding a turbo will use the pressure from your exaust to spin an impeller forcing more air into the intake. (Just the general explination of what a turbo is for anyone who doesn't know.)

In doing so you will change the amount of exaust pressure generated by the engine. Most likely this is not specifically monitored. However the Oxygen Sensors may be effected by the change in pressure or heat caused as a variable as of channelling the exaust a different way. Beyond that, you may bypass the O2 sensor all together, which will cause a fault light because the computer will not know why it is not getting a reading from it.

Furthermore, you will be changing the amount of air pressure in the intake. This will effect the MAF/MAP sensors. (Manifold air flow and manifold absolute pressure. Your car most likely has a MAF, I believe MAP is what they are called on older models.) This change in pressure will be detected by the computer, and it will attempt to compensate. Unless the pressure exceeds what it can compensate for, and then your air/fuel mixture will be screwed up.

Furthermore, the now famous EGR sensor/value works by introducing hot exaust into the intake manifold to warm the incomming air. The turbo wil likely do this instead, that might confuse the EGR, but it will likely just stay closed all the time. Unless it really needs to be open, but because of the increased air flow/pressure in the manifold it cannot vent any exaust into the manifold.

My point is, you cannot just add something and have the engine magically gain horsepower. Anything you add will mess with the engines diagnostic sensors. The engine may or may not compensate correctly, and you may or may not get the full predicted horsepower.

The only thing you can be certain of is burning more gas:
a) The car will have to do more work to run a superchager or turbocharger, thereby burning more gas
b) Anything you add to cause the car to burn more gas will screw with the cars diagnostic engine sensors, valves, vacuum, and EGR components. If the car cannot compensate adaquately, you'll end up losing efficency. That is, you'll use more gas but you won't necessarily burn it effiecently.
c) You'll fail your next emissions test

Plus, if you didn't install the turbo correctly you might shred the impeller. Or you might ruin your catalitic converter. Or if you don't put a temperature sensor in the manifold, you over heat your engine and blow it to bits.

There are some aftermarket additions available to compensate for the programming of the computer, but not a lot. (These computers are just now being understood. Usually the only ones really looked into are one for high performance engines, like the LT1, LT8, L67, etc.)

I saw a product listed on eBay last night that looks rather interesting. I'd called the Venom 400. Bacially it's a little box the you basically wire in-between the trottle position sensor, manifold air flow sensor, and such things like that. When the box is turned on, it reads the varibles being sent to the computer by the sensors, and then modifies them for maximum engine performance before relaying them to computer.

You'll lose 1-3 MPG when it's turned on, but you'll gain a good percentage of the potential horsepower in the engine. Plus, it's equipped with an on/off switch so you can turn it off when you don't need it. I.E. For emissions certification and such. (Remember, many times engine horsepower is limited an extra 10-20 percent if the car can gain a Ultra Low Emissions Vehicle, ULEV, certifiacation because of it.)

The downside, it's only compatible with certain cars and certain engines. I.E. The ones they have tweaked the values on with the help of a Dyno. Who knows if it will work with the 3800-series engine, but there's a good chance it would. As they also put this engine in several... cars people like to go race on the weekend.

Anyway, I think it cost like... $275 or so. Too rich for my blood, the car already had plenty of horsepower for me, and my #1 concern in life is fuel economy. Thus, I didn't bother to E-mail the guy for any extra information.

The point is, if it's compatible with your car/engine it would be compatible with your computer as well. As the purpose of the module is to read engine diagnostic varibles from the sensors and tweak the imputs to the computer to create the maximum safe horsepower the engine is capable of.

Kid_Buick_98&84
11-04-2004, 11:23 PM
So pretty much adding anything major to the engine is out...what are some suggestions of other smaller "tweeks" to improve the engines performance?

avatar307
11-04-2004, 11:28 PM
Hmm... you could try ram air. As long as you don't max out the MAF (mass air flow) sensor, the computer should compensate by pushing more fuel to provide the correct air/fuel ratio as determined by your primary O2 sensor. So... you'd burn some extra gas for sure. LOL

I've been thinking about adding boost fans to my air intake box just to see what happens. Well... that... and I have some extra 24VDC fans that I could run at 12VDC.

Kid_Buick_98&84
11-05-2004, 12:27 AM
Where are some good places to find out more about ram air?

avatar307
11-05-2004, 11:29 AM
How about... http://www.3800tech.com/forum/ made possible by http://www.intense-racing.com/ which specializing in adding performance to the GM 3800 series engines.

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