Extra HP & Torque

[Rodya234]

4.9 turbos have been done before, I wouldn't think it would be too complicated to get one into a Deville. You already have oil lines for the oil cooler, so that eliminates that problem, and if you ran with 5-7lbs of boost you could get away without using an intercooler.

[red_ghost]

http://www.cardomain.com/ride/646305

I remember now. I'm impressed. Still a little skeptical of the 0-60.

[Ghost C]

Originally Posted by red_ghost

Daily: 2001 Jaguar XJR, modified with cold air intake, arden springs, and flowmaster exhaust. Like I said, I had this deville stock for a while. I know how a deville handles. The weight difference in a stock deville vs fiero is about 800 lbs. Fiero: 2790 lb, Deville: 3519. Sorry, I was originally looking at 4 cylinder weight for the Fiero.

Stock what? Stock wheels, X Radial tires? Brand new bushings all around? Un-worn springs and struts? New hubs? Stock is a relative term. The DeVille (especially the DTS) was capable of out-turning many cars of its time and with suspension modifications, has been known to beat many newer cars in the twisties. But it doesn't matter if your suspension components are worn because one bad apple can ruin the whole barrel.

Ceramic throttle body won't help, but the bottom of the intake manifold will repell heat, allowing more head to stay in the block. like I said, been done for a while.

Actually the point of coating the underside of the intake manifold is not to keep more heat in the block, it's to stop the heat soak into the manifold for cooler intake charges. Which still won't net you any noticeable horsepower on a 4.9. You may as well increase the intake valve size and increase the compression ratio while you're at it, because those won't do shit either. All cookie, no cream. Or maybe all cream and no cookie.

So you're saying your deville has a curb weight of less than 3100 lbs? There must be nothing left of that interior. Wouldn't imagine it would be that comfortable in driving.

3,121lbs to be precise. Comfort is a relative term. I find comfort in knowing my car is faster than the next guy's.

I also just updated my cardomain to reflect the car's current specs, because I get around to updating it about twice a year.

[red_ghost]

I suppose before I should have said "not fast" I should have said what I consider fast. Either way, maybe you should have questioned before attacking.

[Ghost C]

I'm a bit crankier than usual thanks to salmonella poisoning, either way, let's get back to the topic at hand.

Advance the timing. Fast and free, albeit mildly irritating.

Look into the Sun Auto Hyper Voltage and Hyper Ground systems. Not well known amongst many American tuners, the setups do, in fact, offer mild to moderate improvements for the engine. You'll gain anywhere from 2-10hp and 2-20ft/lbs with their products.

Intake. The stock intake inlet location is good for cold air, but the flex "ribbed" piping and the tiny inlet size choke the intake. Replace it with something that will still draw cool air but with a larger size, less bends, and no ribs/sharp edges internally, you'll see gains.

Exhaust. Nobody makes a universal product, pick your muffler and get it put on. AVOID FLOWMASTER AND SIMILAR MUFFLERS LIKE THE PLAGUE. They -do not- offer performance gains, and they sound absolutely terrible on a Cadillac, unless you want people thinking you drive a 1983 Camaro. Please, guys, stop putting these god awful things on your Cadillacs.

Plugs, stick with Denso, Delco, NGK or Accel. Platinum yadda yadda multi tipped iridium crap, avoid it like the plague. The U or V-Groove plugs can give a performance benefit. I'm running Denso regular plugs, they do fine. I'll be upgrading to Accel U-Grooves sometime. Index your plugs too.

Plug wires, use whatever you want. I run stock replacement, alot of people use Accel or MSD 8mm wires, I will too when I get around to upgrading the entire ignition setup. They're worth the few dollars more that they cost, especially if your wires are in need of replacement anyway.

Coils, big lots of argument there. Do you want coil on cap? If so, get one of those, but compare all the brands. Do you want to get the conversion piece and use a seperate coil? It gives you alot more options. Most 4.9's would never need the seperate coil piece.

The chip is basically pointless now that there are widely available prom burner type things that anyone can use, which basically means if you know what you're doing you can burn your own chip to your exact specs for about the price of the FastChip, and if you ever change your setup you can re-tune yourself. Or have someone else do it, since I know there are people on here with that knowledge.

With the CAI and exhaust, your major choke points will be the intake manifold and the exhaust manifold. Since nobody is going to build a 9,000rpm 4.9, the exhaust manifold is pretty alright for getting the job done, so leave it be. Port the intake manifold, it's good for some power. Port the heads. But don't bother with upping the intake valve size like some Fiero owners, it does dick-all to make more power. Neither will raising the compression. If you're really into it, get the Allante intake manifold, plenum, and throttle body. It's good for 20hp and 20ft/lbs by itself. Port it, too, if you're feeling froggy.

Add a turbocharger. See, the 4.9 is a pretty easy V8 to single turbo, actually in general, because you don't need a turbo manifold thanks to the dumb ass crossover pipe design. Fab up a blockoff plate for the rear exhaust manifold, weld a flange onto the crossover pipe, and you got yourself the makings of a turbo setup. 5psi on a 4.9 will ruin pretty much anybody's day, thanks to the 290-300whp and 350+ft/lbs you'll be making. If overall power is your goal, I recommend this route over any others. Beef up the transmission or be gentle off the line, though, else you'll be spitting gears on the pavement.

[red_ghost]

Originally Posted by Ghost C

I'm a bit crankier than usual thanks to salmonella poisoning, either way, let's get back to the topic at hand.

Advance the timing. Fast and free, albeit mildly irritating.

Look into the Sun Auto Hyper Voltage and Hyper Ground systems. Not well known amongst many American tuners, the setups do, in fact, offer mild to moderate improvements for the engine. You'll gain anywhere from 2-10hp and 2-20ft/lbs with their products.

Intake. The stock intake inlet location is good for cold air, but the flex "ribbed" piping and the tiny inlet size choke the intake. Replace it with something that will still draw cool air but with a larger size, less bends, and no ribs/sharp edges internally, you'll see gains.

Exhaust. Nobody makes a universal product, pick your muffler and get it put on. AVOID FLOWMASTER AND SIMILAR MUFFLERS LIKE THE PLAGUE. They -do not- offer performance gains, and they sound absolutely terrible on a Cadillac, unless you want people thinking you drive a 1983 Camaro. Please, guys, stop putting these god awful things on your Cadillacs.

Plugs, stick with Denso, Delco, NGK or Accel. Platinum yadda yadda multi tipped iridium crap, avoid it like the plague. The U or V-Groove plugs can give a performance benefit. I'm running Denso regular plugs, they do fine. I'll be upgrading to Accel U-Grooves sometime. Index your plugs too.

Plug wires, use whatever you want. I run stock replacement, alot of people use Accel or MSD 8mm wires, I will too when I get around to upgrading the entire ignition setup. They're worth the few dollars more that they cost, especially if your wires are in need of replacement anyway.

Coils, big lots of argument there. Do you want coil on cap? If so, get one of those, but compare all the brands. Do you want to get the conversion piece and use a seperate coil? It gives you alot more options. Most 4.9's would never need the seperate coil piece.

The chip is basically pointless now that there are widely available prom burner type things that anyone can use, which basically means if you know what you're doing you can burn your own chip to your exact specs for about the price of the FastChip, and if you ever change your setup you can re-tune yourself. Or have someone else do it, since I know there are people on here with that knowledge.

With the CAI and exhaust, your major choke points will be the intake manifold and the exhaust manifold. Since nobody is going to build a 9,000rpm 4.9, the exhaust manifold is pretty alright for getting the job done, so leave it be. Port the intake manifold, it's good for some power. Port the heads. But don't bother with upping the intake valve size like some Fiero owners, it does dick-all to make more power. Neither will raising the compression. If you're really into it, get the Allante intake manifold, plenum, and throttle body. It's good for 20hp and 20ft/lbs by itself. Port it, too, if you're feeling froggy.

Add a turbocharger. See, the 4.9 is a pretty easy V8 to single turbo, actually in general, because you don't need a turbo manifold thanks to the dumb ass crossover pipe design. Fab up a blockoff plate for the rear exhaust manifold, weld a flange onto the crossover pipe, and you got yourself the makings of a turbo setup. 5psi on a 4.9 will ruin pretty much anybody's day, thanks to the 290-300whp and 350+ft/lbs you'll be making. If overall power is your goal, I recommend this route over any others. Beef up the transmission or be gentle off the line, though, else you'll be spitting gears on the pavement.

I might do a turbo. Figure I might as well with everything ripped out. I heard the alante manifold would help. saw it on a 4.9L fiero. I was actually happy with my flowmaster. I doubt there were any performance gains. I have a 50 series delta flow on it. Silent inside the car and the outside it has a throaty growl at a high RPM.

[Ghost C]

I think they sound like ass, which is a matter of personal taste. But statistically, rarely do they perform better than stock, and in some cases they've actually been tested to perform worse, which is what I REALLY don't like about them. Straight through design is the way to go.

I also forgot to add the Accel cap and rotor kit is worth the $23 or whatever it costs, and should be purchased as a standard replacement for any stock or OEM-replacement equipment.

[red_ghost]

will hyper ground and such really improve that much? How efficient is it in comparison to running reguar 4 guage wire? I was planning on upgrading my wires. I also have about 20 feet of 0 guage blue wire left over from the batteries in the trunk.

[red_ghost]

also when it comes to exhaust and hp, wouldn't a glasspack almost be the best thing because of its flow? Not sure how it would sound on a 4.9L. Sounds pretty cool on a caddy 500!

[quins90lac]

what kind of wire is it . you could always do a big 3 bu runing it from your alt to the batt fused in between with at least a 250 amp fuse and then batt neg to body ground and then engien ground to body ground . it will help your charging system if nothing else . then you could upgrade to a 250 amp alt from mechman with an external voltage regulator

[Ghost C]

Originally Posted by red_ghost

will hyper ground and such really improve that much? How efficient is it in comparison to running reguar 4 guage wire? I was planning on upgrading my wires. I also have about 20 feet of 0 guage blue wire left over from the batteries in the trunk.

The Hyper Ground setup is essentially the same as any other ground wire setup that's simmilar, ie the HKS Circle Earth and such. You can look up the list of grounding points they use and do it yourself, however the Hyper Voltage system is something which to my knowledge has not been replicated by any other parts maker. You see products advertised as the same on ebay and other disreputable tuning products dealers, but they are decidedly not even close to the same.

As for gains, on most of the different applications I've seen tested, they gain a wide variety of power. Some cars will net a horsepower and a half and other models have gained as much as ten. It will increase your torque more than horsepower, and it will increase the crispness of the throttle.

The generally accepted school of thought is, newer cars in general will benefit less from the ground wire and voltage systems than an older vehicle, as manufacturer's have been picking up on these ideas and implementing them from the factory. I can tell you that aside from the exhaust ground strap on the 4.9 DeVille (which could be bigger), the grounding system leaves something to be desired and should be upgraded, whether it's DIY, Sun Auto, HKS, or another reputable brand.

also when it comes to exhaust and hp, wouldn't a glasspack almost be the best thing because of its flow? Not sure how it would sound on a 4.9L. Sounds pretty cool on a caddy 500!

Pretty much all of the "ricer" or tuner style mufflers are glasspack design, they're just not the same as a Cherry Bomb or such. I run a single in dual out tips-on-muffler that's glasspack, and has resonated tips. There's a huge variety of designs that would suit even the pickiest individual in these style mufflers. Or you could just run a cherry bomb with resonated tip(s)

YouTube - 4.9 DeVille exhaust pressure

It sounds a little different when not recorded through a cell phone, but in general it's much smoother sounding than a chamber design muffler, not as irritatingly deep and flows much better. It does get alot of condensation in it compared to the stock design, though.

If there was one thing I would change about my exhaust it would be to change the muffler from 2.5" to 3" inlet, which brings me to another point, keep as much of your stock exhaust as possible. 2.75" mandrel bent exhaust is not cheap to come across and should be saved. Most exhaust shops will try to give you crush bent 2.5" in its place, which is totally unacceptable.

[quins90lac]

see now i have the cherry bomb turbo and i just put it in place of the stock but ive been thinking about cutting it off at the end of the long strait and runing a splitter pipe and then in to 2 of them with some square tips. i like how the cherry bombs have a sweet spot around 2000 rpm's

[ehall]

The three most noticeable changes I've made to my 4.1 are advanced timing, Borla muffler, and Accel 8.8 wires (bought to fix a buzz but improved line response surprisingly). At some point after I finish working on my Jeep I'm planning to swap a 4.9 block under my 4.1 TBI intake.

Performance tuning of a four-stroke engine is pretty much universal. The first down stroke has the cylinder suck air and fuel into the combustion chamber, the next upstroke compresses it, then the spark ignites the mixture and pushes the cylinder down, then the next upstroke expunges the exhaust. Only one of these strokes produce power, while the other three consume power.

Most bolt-on mods simply aim to reduce the amount of power that is consumed as waste, and do not actually produce a better power stroke. IE, better airflow in and out of the engine results in less energy being consumed on sucking air into the chamber and expunging gasses exhaust out, which in turn allows a larger remainder of the existing power stroke that can then be used by the drivetrain. High flow is key to this, but don't confuse "bigger" with "better" on exhaust--you need to manage back-pressure in the exhaust for scavenging to work right and you will have to use a size that is appropriate for maximum torque at a specific RPM band.

You can also do some simple things to improve your power stroke. IE, better ignition parts will produce a more consistent explosion which yields a less ragged power stroke, while an earlier ignition will produce a longer power stroke that produces more power.

You can also do some things to the drivetrain, such as regearing for lower torque, although this will negatively restrict top-end capability.

In the end there is no replacement for displacement, and if you really want to burn the rubber off your wheels you will need much more combustion.

[93DevilleUSMC]

Some of the claims made about the 4.9 on here are bull shiat with a free cow thrown in.

[red_ghost]

Are the distributors on the SBC the same as whats on the 4.9L? I'm asking ebcasue I was going ot just buy a complete Accel distributor with a supercoil.