Generation IV External Engine - what bolt on mods to get my 2006 ls2 to 400whp?

I have a 06 goat, and its a 6 speed model.. I have 3000 to spend on mods and im not looking for nitrous, turbo or supercharging.. what mods should i get to bump my power to around 400whp? I know im not too far off stock.. so if i can do this without power adders or even a cam.. how do I do it? or how would you do it?

Thanks:engarde:

would adding 1.75 ratio roller rockers, cold air intake system, long tube 1 7/8" headers and 3" true dual exhaust put me there? with a ls2 or would I still need more being that its a stock motor for 400whp?

headers and a true dual exhaust should put you close to 400rwhp. you will pick up a few horsies with cold air intake and k&n filter as well. the mods you have listed should put you close to 400hp with a tune.

you could do free things like porting and polishing your MAF ends and throttle body.

other things to consider:
- pulleys
- gears (wont add hp, but it will wake your car up)
- lightweight flywheel/clutch assembly (will free up some hp)
- fast intake (not that much of a gain as ls2 intakes flow pretty good)

yeah, ill have true duals put on of course.. i doubt ill do a lightweight flywheel but thanks for the idea.. pully is def something i would consider.. i just dont really want to tear into my motor if i dont have too..

whats the largest lift cam i could put in a stock ls2 on its springs.. i wont be doing a cam but its still something id like to know.

Thanks

full exhaust and a tune would get you close. springs are easy to swap on the car, so i wouldnt limit your cam choices because of springs.

1 3/4" or 1 7/8" LT's and full dual 3" cat back (about $1800 with Cats)
+ Ported manifold and TB (ls2portworks does a core return policy to reduce your cost)
+ Cold Air Kit & finish it off with a tune.
Total Package after install will probably be right over the $3000 that you have but it will get you really really close to your goal.

Note: The manifold is one of the restrictive points on the LS2 (LS6 stock flows better but will not work with your 90mm tb).

Headers and exhaust: SSW (Stainless Steal Works) makes a full dual 3" cat back as well as 1 3/4 Long Tube headers (I purchased mine through speed inc).

K&N makes a decent Cold Air Unit but there are newer setups out there (one being the OTRCAI called Vararam).

Next up will be the Cam and Spring upgrade to get you around 450rwhp :)

I just went on ls2portworks.com.

I guess they are closed down.

hmm.. anyone else do porting work on the ls2 intake and tb? i wanna keep the ls2 cam stock for now just to see how i like it.. then later on I can do a cam/spring change.. but id still like to know whats the max i can do ont he stock springs? I do have a .557" lift voodoo cam i could use in a ls2 if i wanted.. but i dont have springs to go with it..

thats why i mention the springs.

The stock Springs are rated for .550" lift and that is .557" cam would be pushing it for the stock springs.
Some people have gone with cam's that put them close to .575" lift with the stock springs, but they end up with valve float in the upper rpm.

And I didn't know that ls2portworks was closed :( I have not been to that web site for a while.

Fasterproms does porting and they are a sponser as well.

Cory shut down? man that sucks-he ported my LS6 intake-does great work:)

i understand, if i do a cam change ill do springs just to be safe. i dunno if ill do a camchange at all for right now.. i may wait a year or so to see how well i like the stock bolt on ls2 for starters.. and if i need more save n buy springs and a cam to have installed n tuned.

Ported fast 92/stock ported tb. Headers, true duals and tune and you should be over 400.

All you need is a good set of heads, 400 is easy. ported or aftermarket heads and your 400+

well i have a brand new set of 5.3L patriot stage 2 heads i can use. however would those even be good on a ls2?

Yes they would work great.
Head work should always be your 1st upgrade.

well i have a brand new set of 5.3L patriot stage 2 heads i can use. however would those even be good on a ls2?

Keep your stock 243's, they're just fine.

You want 400 rwhp with just BOLT ons?

- Headers, primary size is all up to you
- x or h pipe and catback system
- cold air intake
- 1.8 roller rockers with a good spring kit
- ported intake and TB
- Tune

that right there would put you around 390rwhp+ with gobs of torque as well.

your stock 243's are not even close to fine, compaired to a set of stage 2 heads that you already have. just bolt them on then go to the track and tell all your new times. and then do the above upgrades when you have the extra cash.
with just the heads you will have more power than doing anything else bolt on.

ya see I like the sound of not really opening up my motor to get to that 400whp mark.. i like the idea of it still being factory sealed. bolt ons are all i want to go with at this point in time. later on we will see..

i do have those 5.3L heads for sale guys if anyone is looking for a set? 1100 shipped.. brand new in the box.

Factory sealed is code for slow,
dont race anyone I've done work for, your seal factory seal will see only tail lights.

never planned to be the fastest around town. if i wanted more than 400whp id make it happen.. but since im trying to keep it tame with just a lil more punch how am I going wrong or trying to win drag races??

well i guess i can always build the ls1 im trying to sell, build a stroker 383 one and use those patriot heads and get around 450-500whp n/a and then sell my ls2... hmm... only if i wanted too...

just re-read what i wrote man. what i said i didnt say to sound bad like it does.. so im sorry i was just stating its def not my goals to be the fastest around.. i just want more pep and 400whp will be plenty for me.

well why ask for help if you already have a plan? you have 450 in a box you dont want to open, thats just crazy. but its your deal man good luck with it.

cause i wasnt sure if it would net me my goal of 400whp without opening it up, i was hoping just bolt ons would get me there.. and it seems they will without boost or nitrous.

Your best bet would be a cam.

thanks, on the note of the cam just to end my thought process :)

what is the largest camshaft you can install on a ls2 engine if you change the springs also.. meaning how much is too much before valve to piston clearance becomes an issue?

is a .600" lift cam with 1.7 rockers too much on a ls2 if you change the springs to match?

thanks, on the note of the cam just to end my thought process :)

what is the largest camshaft you can install on a ls2 engine if you change the springs also.. meaning how much is too much before valve to piston clearance becomes an issue?

is a .600" lift cam with 1.7 rockers too much on a ls2 if you change the springs to match?

No .600" lift is not to much with a spring upgrade. Pac .600" behives, Comp 918's, etc (reuse the stock retainers and locks).

Just to give you an Idea.... I'm setting at .617" intake and exhaust (Voodoo 222/228 with comp 1.85" rockers) with Patriot heads that have 2.055" intake and 1.57" exhaust (64cc chamber size)

No PVT issues on my end with stock pistons and stock GM Gaskets.


If I could start all over again... I would have gone with the Voodoo 232/238 cam (Lunati 60512 - .599"/.601" lift with 1.7 rockers) + Pac or Comp .600" Springs and would have kept the stock gm 1.7" rockers and heads.

When I started I picked up the cam, along with a set of comp 918 springs and comp 1.85" rockers.
I noticed that the 1.85" rockers put the cam above the 918's recommend lift (which Comp lists at .600").
So I returned the springs then looked around and found the Patriot Stage 2's with .650" dual springs already installed.

Stock the Voodoo 222/228 cam has a lift of .567" intake and exhaust with 1.7 rockers (Lunati 60511). Changing the rocker arms out from 1.7" for longer 1.85" units put the lift up to .617".

I've got about 24,000 miles on the head/cam/rocker combo (I only put about 200 to 250 miles on her a week). I'm just wondering how long the Patriot .650's will last with this combo.

One thing I've been looking at recently is that 96mm aluminum manifold (satin finish with fuel rails is like $480, which is alot less then a fast 92 without rails). Some people Hate it some people don't.... I'm just not a big fan of spending $800 (on average) for a manifold then another $80 for a kit that allows me to reuse my LS2 fuel rails and injectors.

you know I have that exact camshaft already for a ls1 i was going to build... do you think i should just use it for my ls2? and as for rockers i have 1.75 ratios not much of a gain over stock but still a lil more.. prob would net me around .575 i would assume.. if i go with a cam that is..

your stock 243's are not even close to fine, compaired to a set of stage 2 heads that you already have. j


Coming from a guy who says 853 castings, with STOCK VALVES will provide 100 hp increase :eyes:

Takes quite a skilled porter to take 243/317/799 castings using stock valves to produce a 100hp gain over stock but you can do it with 853 castings? Sorry man, but the stock 243's will put up a MUCH better fight than you think against a budget set of 5.3 heads, larger valves or not.

Op is better off not listening to you, that's for damned sure. Maybe you can fix him up with one of them "swirl port" jobs.... :ripped:




OP, good luck man. If you choose to stick to bolt ons, the list I provided works well. If you do a search, you'll find the same combo duplicated over on the GTO forums and it performs rather well. If you decide to go for a cam, be wise about it and don't go after a huge donkey dick cam and peak HP numbers. Your GTO is 3800lbs +/- and is going to need something with a very broad torque curve unless you're planning on gearing the car and gutting it.

I've got about 24,000 miles on the head/cam/rocker combo (I only put about 200 to 250 miles on her a week). I'm just wondering how long the Patriot .650's will last with this combo.

I would check those springs ASAP if it were me. Can't ever be too safe with your valve train and considering you're using some 1.85 rockers with a cam, I'll bet those springs have taken a beating over the course of 24k miles.


One thing I've been looking at recently is that 96mm aluminum manifold (satin finish with fuel rails is like $480, which is alot less then a fast 92 without rails). Some people Hate it some people don't.... I'm just not a big fan of spending $800 (on average) for a manifold then another $80 for a kit that allows me to reuse my LS2 fuel rails and injectors.

Well essentially, you get what you pay for in terms of power between the two manifolds. The Typhoon has its place for being a nice budget intake but if you're looking for a solid, proven performer then the FAST is a no brainer. Especially if you're looking to upgrade to a stroker or want to revise your H/C setup later down the road.

thanks lilbuddy,

Im thinking ill stick to the bolt ons for now and see how well i like it.. If i feel i need more later on, I can then debate the camshaft issue and discuss it with you guys on here on what choice i should take.. I feel ill be happy tho but well you never know.. :)


also I was looking at the typhoon intake.. knowing its not the best out there however im sure its better than stock, id just need to find a nice place who can port one out.. plus on ebay it comes with nice fuel rails and it is a good looking peice from the pics ive seen..

It would be rediculous to put a cam into a stock engine without any other mods done. The power potential would greatly diminish without the use of LT headers, a good set of mufflers, a nice intake setup and a solid tune. Go with the bolt ons first, they are easy and if its not enough, then start looking at tearing apart your valvetrain.

Food for thought; you dont always need to add parts to make a car faster....

please read my posts.. i have long tubes and regular basic bolt ons.. i was debating wether a cam would even intrest me or not for what my goals are. but thanks for the insight your thoughts are mine too and have been.. im not intrested in being the fastest car on the block.

1 7/8 long tube headers, 2.5" Corsa performance exhaust, no cats. Add a cold air intake and a good tune and you have 379 RWHP and 380 TRWTQ. what my dyno read. Also if you have a T56 you definintely will fall in love with a short throw shifter. My next goal is to put in a nice cam in and head work to get 500 RWHP.