When we bought the 05 it had the following mods: CAI, aftermarket plenum(dont know brand), DC headers, test pipes(dont know brand), uprev tune.

Test pipes ended up cracking almost the entire pipe circumference; so we picked up some ART test pipes last week.

Got the pipes on and got her tuned(dynojet dyno).. old tune put down 248/239.. new tune 261/243..

Car obviously sounds much better (even before old test pipes cracked), no rasp, and the HP increase is noticeable.

Can you guys give me some suggestions/recommendations for mods to get up to 280WHP?

....the next logical step seems to be catback; I have kept the stock cb on because it sounds great and is not overly loud, any suggestions on a quite catback with potential to increase flow over stock cb??

Any help is much appreciated!

 

Since it's an '05, I'm assuming it's not a Revup. You're never gonna hit 280 without long tube headers and cams. A lot of work/money for not much more power. If you're hurtin for more power, start saving up for F/I.

 

Cams, some high performance spark plugs, idk if lightweight underdive pulleys will do much, maybe get a full proper tune up to restore any lost power.

 

Is the 280 the next step in your mind? As for long tubes being required to make 280 NA, no it isn't, an exhaust won't really make much power for you. At the point you are at, you really need to make a decision if you want to spend $10k to get over 300hp NA, or spend $10k to get over 400hp with a super or turbo charger.

 

This forum really has reached the point where "performance spark plugs" is a mod...

 

I hate how's there no in between with these cars. It's either a little power or tons of power.

 

Don't bother with any more intake mods, the invidia exhaust is pretty quiet. I have the stillen true dual and it's plenty quiet unless your at 80%+ throttle…which I love.

if you want more power look into a supercharger, it'll get you to 400whp and will compliment your other modifications. If you turbo, you'll throw away the time and money spent on the headers (although you could sell them used). But the 300whp mark is unachievable w/o FI. You'll spend $7k to $10k all in to get to 400whp, which isnt too shabby all things considered.

 

I never said it was a mod. Just like getting a tune up isn't a mod either.

 

There's no such thing as high performance spark plugs...

 

Op just buy the most expensive stuff and eventually you'll get 280.

 

Don't listen to him, listen to people who have done this. People run good old NGK's and the only thing that changes is the plugs get colder...

 

Like with most things we do with our cars,there is usually a budget.
What do you have to spend?If you got the bucks,spring for an Amuse
exhaust system.A cam change would be a good idea.A bigger throttle body
may work.From what I can see from the pic,it looks like you have a Crawford
plenum.Or maybe "plastic" plenum from Kinetix.

 

TO get 280 whp:

True dual catback or a good single back exhaust
Some mild to agressive cams
ported and polished lower plenum and upper plenum
intake manifold gasket
headers
good tune

 

Thank you all for your replys and information.

To those that have gone the supercharger route: How much has your reliability been affected (this is a daily driver)?

It makes sense, given the relative investment, to go with FI and get the hp/$. However, if reliability is drastically affected and therefore prompts more $$ to maintain/fix issues that arise, it seems like that hp/$ ratio likely evens out?

 

Just a suggestion or alternative to power- 3.7, 3.9, or 4.08 final drive depending on potential future FI route.

 

I can't speak from personal experience but a modest vortech setup correctly should be pretty reliable. The engine will take the power on stock internal to about 400-450 tq.

 

If it were me I would go with the F/I route but I woukd supercharge it instead of turbo. You can keep your exhaust parts you have already bought. Also you get the power that you are looking for. ^^mr. Sparco has a good point about gearing too. A set of 4.08 gears will make it quicker. With the same hp.

 

You don't need cams to make over 280whp on a DE. My buddy Russ just put down 286whp on his 03 and it's got 280k miles on the engine. Don't listen to the average bull that's on this forum. Do your research. Cams are necessary if you want to get near 300whp on a DE, not 280.

 

Just a question but what kind of dyno was it?

 

That has to be some kind of record. There are HRs with PPE headers making only a little more than that.