Extra HP & Torque

[Sporty883]

I'm sure there is a thread about this already, if so can you please point me to the page or title. What I'm wondering is what can we do to our early 90's 4.9liters to give them some more HP. I haven't been able to find a performance chip, cold air intake or aftermarket exahust made for these models. Anyone know what I could do and where to get it.

Thanks

[Rodya234]

Now your speaking my language.

Fastchip makes a ECM Prom for our 4.9L engines. It advances timing to 14-15 degrees BTDC and eliminates the top speed limiter (which is 112mph btw)
HP Yield= 10-20bhp, depending on the health of your ignition system.

The 4.9 already has a cold air intake, the problem is that the intake mouth is only about an inch wide. Evoluzione Engineering makes a 3'' Intake for 4.9's, as well as a few other performance parts for Deville.
HP Yield: 15-20bhp

Your pretty limited on exhaust, unless your able to do custom work. The biggest improvement you can make is higher flowing muffler and cat. Really any muffler that's offset in/center out will work.
HP Yield:10-20bhp, depending on what kind of muffler you get. '


There's a few more non-invasive things you can do, but I'm hungry and don't feel like typing now. These are your biggest non-invasive performance mods though.


Disclaimer: HP numbers are estimates, and your actual numbers may vary. Note that this is also HP at the flywheel and not at the wheels.

[quins90lac]

you can make you own cold air intake on the cheap all you need is a 2 ft metal dryer tube and a cone filter available at auto zone for 25 and then the tube witch is about 15 their you go a cai for 40 . the other thing you can do on the cheap is advance the timing to 12-14 btdc but if you start to get pinging back it off. as far as a write up look for a guy on hear that goes by illumina he has allot of good write up on more hp out of these engines

[Brizzal]

4.9 performance = custom work....it sucks...

[Rodya234]

Originally Posted by Brizzal

4.9 performance = custom work....it sucks...

Very true, but it makes the experience much more rewarding than working on a car that everyone makes performance parts for. The finished product isn't too shabby either.

[Sevillian273]

Here's a couple modded 4.x caddys for your viewing pleasure. might give you some ideas fwiw

http://www.cardomain.com/ride/3112359

http://www.cardomain.com/ride/569881

[red_ghost]

ceramic plate the bottom and top of the intake manifold for a 10 hp gain. Keeps the inside of the combustion chamber hotter for better combustion.

[Raze]

Originally Posted by red_ghost

ceramic plate the bottom and top of the intake manifold for a 10 hp gain. Keeps the inside of the combustion chamber hotter for better combustion.

I'm sorry but my bull$hit detector just went off. Please provide the dyno graphs from before and after as well as the ambient conditions of both runs...

[red_ghost]

Originally Posted by Raze

I'm sorry but my bull detector just went off. Please provide the dyno graphs from before and after as well as the ambient conditions of both runs...

uh sure, if you want to buy me a dyno

This has been done on hotrods for the last 40 years...

[Rodya234]

I've been doing some research into this, and apparently European car manufacturers have started ceramic coating their exhaust manifolds on a lot of their cars. While they say that the horsepower is a bonus, the true reason behind the sudden coating is to help the car to pass the Euro 5 emission standard.

I can understand hotter exhaust temp= higher velocity gas, and the hotter temperature may help to burn unused fuel, but I'm curious to how it would feel on a street car.

red_ghost, if you would be so kind to answer my questions, what parts did you get ceramic coated? I'm starting to think that getting my exhaust manifolds done wouldn't be a bad idea.

[red_ghost]

Originally Posted by Rodya234

I've been doing some research into this, and apparently European car manufacturers have started ceramic coating their exhaust manifolds on a lot of their cars. While they say that the horsepower is a bonus, the true reason behind the sudden coating is to help the car to pass the Euro 5 emission standard.

I can understand hotter exhaust temp= higher velocity gas, and the hotter temperature may help to burn unused fuel, but I'm curious to how it would feel on a street car.

red_ghost, if you would be so kind to answer my questions, what parts did you get ceramic coated? I'm starting to think that getting my exhaust manifolds done wouldn't be a bad idea.

I'm still waiting for mine to come back from the plater. I am getting almost everything in the upper engine compartment done except the heads. Intake manifold, throttle body, that little pulley that attaches in between the intake manifold and power steering pump, exhaust manifolds, crossover pipe, plus just about every bracket. The main reason I'm doing it cosmetic. The plater said my parts are done and currently being polished. I would assume that means I will have them by early next week.

There is a guy in town that has a 54 Bel Air who said it gave him about 20 extra horsepower but it is relative to the engine and based more on an original horsepower basis. That's why I am estimating about 10. Its possible for it to be less, but I hardly care about that. It looks good.

[Rodya234]

Interesting.

How much do you think it would cost to get the TB, Intake and Exhaust manifolds coated?

[red_ghost]

Probably $300. Pain in the rear to pull that stuff all apart though.

[Raze]

Exhaust manifold plating is beneficial, more so for turbocharged vehicles, though higher exhaust temps for N/A vehicles does help scavenge, but the point I was making was intake plating isn't going to do jack, period. For a lot less you can get high-temp ceramic paint (in a rattle can), spray up your exhaust yourself ($15 or so), and then get header wrap ($30-60), wrap your exhaust and really see high exit temps, my point is performance, not looks...

[red_ghost]

I don't see how performance matters too much on these cars. They have a base of 200hp. Even if someone was able to get it up to 300 the tranny wouldn't take it. Even at 300, that's still not very fast.