I'm looking for something new to do to my 1989 Firebird Formula 350 WS6. It has the following done:
1.6 Roller Rockers
Trick Flow Twisted Wedge G2 Heads
Ported Plenum
SLP Runners----not yet ported
stock mainfold base smoothed out and ported a little
Underdrive Pulleys
Adj Fuel Pressure Reg
MSD Ignition and wires
K & N Air Filter
58mm Throttle Body
Nitrous----150hp shot
Flow Master Muffler----80 series

What would be the next best bolt on? :lala:

 

Headers, high-flow dual cats, 3" cat-back.

 

What is a good brand to go with for all that? I hear headman haders have a nice kit for the dual cats setup with a y-pipe included. Are they any good? Thanks for the help.

 

wire seperators/holders

 

lol.....yeah but i'm having trouble finding wire looms for my application. If i get the headers i have really nice billet wire looms. They just won't work with exhaust manifolds. Any other things todo?

 

I just used msd wire seperators and ran them similar to the setup in the picture.

 

Use the Made4U centerbolt looms. They're the best.
http://www.made4uproducts.com/

 

I just picked up the Made4U looms. Will be installing shortly when I get around to the major tuneup.

I don't know about the Hedman dual-cat headers directly. But, I hope they're better than the single-cat y-pipe they put out. If so, then they're probably a good choice.

An alternative would be Hooker 2055's and have the end of the y-pipe modified to go to the dual cats.

 

I highly recommend the Hooker 2055's. And take it to an exhaust shop and cut out one of the cats. Just have them run a 3 inch pipe to a single cat and then hook up to whatever's behind it. Your average muffler shop can do it.

 

Yeah, I go back & forth about the dual- vs. single-3"-cat. Since I'm just running a 305 right now, the 3" is fine.

But, the factory picked up 10 HP using the dual cats on their relatively mild setups. So, the dual system seems to me to still have some merit.

Whether it's "worth it", that's a whole 'nuther question...

 

I'll tell ya what's better - running without a cat period! At least that's what I'm doing and it seems to work

 

I suggest putting on a cut out.....I have a cut out and it sounds bad a$$:rockon:

 

Because of the tall covers? Or, because you've still got manifolds?

Straight boots would work with the manifolds. But, you'll be installing headers soon, anyway...

 

Do what I did with my wires. Works for me, and should work even better for you. Engine looks cleaner too. Route all your wires on the right side of the distributor for the side of the engine (2,4,6,8 on the passenger, 1,3,5,7 on the drivers) and then route them down behind the engine (like behind the valve covers) and then around the manifold collectors. It works best if you have the wire clips that hold all 4 wires and a few zip ties as well. On the driver's side, just zip tie on wire loosely to the lines coming off the brake booster, and then put the 4-wire clip right under it. That way, all 4 are held away from the manifold. Then just do something similar for the passenger side as well. Also, if your wires are angle boots, turn them so the boots point straight down if possible.

I did mine like this, and it looks really clean and they are out of the way.

 

Now if you change the cam and stick a stealthram on that thing you may just pick up 80-100RWHP


no joke!

 

really? What cam do i need? can anyone help?

 

As everyone will (or should have by now) told you your TPI Plemum, Long Runners, and base are the biggest restriction on any high perf. motor.

Now as it sits, if you have the stock cam, you are hardly taking advantage of the heads you have on that motor.

But at the same time, your combo is matched up perfectly fine. stock cam, TPI, decent heads... they go together nicelly.


If you want alot more horsepower, the next step is a change in powerband. since horsepower is a function of torque and RPM, you are going to want to move your torque up to a higher RPM to make more horsepower.

this means two things.

Number 1: Ditch the TPI and stock cam, go with a better intake (stealthram is my opinion) and a better cam (match to heads and stealthram),

Number 2: do not expect any gains at all with this swap unless your drivetrain matches your powerband. this means you will need gears and stall to match your powerband, or you will wind up being slower than stock.

So if you have stock gears and stock stall, then you will want to:

get gears (3.42-3.73)
get stall (2400-3200)
get stealthram (2500-6500)
get cam (2500-6500) something in the 234 - 244 @ .050 should do great.

if you have all of the above with your current heads, then without the nitrous typically you would expect to run a low 12 high 11 in the 1/4 mile with traction, and probably make about 420-440 horsepower @ 6200~Rpms from the looks of the combo.

now add the 150 shot, and although you may make 500-550 horsepower, you will probably fry your bottom end. this is where it gets dicey, and if you run your stock crank rods pistons you may (probably will) blow somthing up. now your looking at bottom end....

So you must use the force and decide what is the best and most cost efficient way to go. just throwing a cam in there isnt going to do diddly.