Im in the middle of buying a 1999 Trans am, its stock other than a set of Patriot ls6 heads, what adavantage do they have over the stock heads??? Im new to the ls1...

 

with stock cam...even with bolt ons...maybe 15hp.

but if they are patriot heads, they've been ported probably...hard to say then.

since you can easily have too much head for a cam...and ported LS6 heads on a stock cam is probably that...too much.

biggest advantage is....its all set for a big nasty cam...can you say F14??

 

yeah, heres the link to the picts, bought it off of here...

http://web.camaross.com/classifieds/...ct=2454&cat=19

 

teke184 is right, since a good set of heads are already on it, it is primed and ready for a nice cam which is the least expensive and fastest part of the mod. but 15 horsepower? PROBABLY been ported? teke184 and I will disagree here with that ALL of Patriots heads are ported and polished....selling ported and polished heads is mostly all Patriot does (plus some valvetrain parts etc, but heads are their main thing).

v-8, to answer your question, a set of heads alone are worth about 35 hp (I am assuming you got the stage II heads). I know that doesnt seem like much but a set of heads and a cam are complementary modifications, they complement eachother, meaning you really need both before you see the real potential in a set of ported/polished heads. if you just have a cam alone, you wont see much power difference, and same goes for just having a set of heads, but when you have both on the car working together, thats when you see the huge difference. The heads are ported to flow more volumes of air, but the cam is required to hold the valves open longer for that extra air to flow through. Understand now why they are complementary mods and work together??

The good news is you just saved the $1800 that LS6 heads cost (at least thats what they were going for last time I checked) and the $300-$400 labor for install. That is the biggest chunk of change involved in a head/cam mod. Now just buy a cam for a couple hundred bucks to go with it, then get the car tuned, and you will be at 400+ RWHP easy, after that I would seriously recommend getting some sticky tires or some lower control arms for traction because there will be a huge power difference.

assuming the rest of the engine is stock, here is my recommendation for cam specs. 226/226 114 LSA a thunder racing TR224 cam is also good (and popular too).

BTW what gear ratio do you have in the car? A lower gear ratio is another thing that goes very very well with heads/cam because it gets you up into the higher RPMs faster. those are the 3 best mods you can do to a car in my opinion.

The reason I speak with knowledge about this is because this is that is the exact setup I have. good luck with it, see ya

 

Thanks for all of the information you posted, as for now the rear gears are stock, ive got a set of 3.73's that came with the car. you are god on the lsx motors, ive built a couple of lt1's but not any ls1's they are completely new, again thanks...

 

Good news is you can get a set of CNC ported LS6 heads for less than $900 shipped to anywhere in the US at your door.

The price came down a little.

Ben T.

 

"a set of heads alone are worth about 35 hp"

not on a stock cam....

ported heads flow great, especially at .550 to .600" lift....too bad the stock cam is something like .525"

so the bigger runner volume and increased high lift flow is almost wasted on a stock cam.

i say almost because there is an increase in flow in the lower lift range...but still not enough to make a huge difference.

but like i said...add a cam....

 

I wont argue, but maybe you missed the GM High-Tech performance article where they did an LS6 HEADS ONLY swap and netted 41 hp (at the rear wheels).

It is in this article...

http://www.gmhightechperformance.com...toc/index.html

Also, a good friend of mine installed mti 2.5 heads and saw 34 hp increase with stock cam.

Either way, yes, the unanimous opinion is to get a stinkin cam and start tearing up the street

 

Hey V-8, Feel like picking up 500 bucks for the extra set of heads you have? Shoot me a PM if you're interested.

 

I totally disagree. There are many many LS1s with cam and boltons with stock heads that put out near 400 hp. LS1s respond really well to cam swaps, way better than traditional SBCs or LT1s do.
Now as stated an engine is an air pump and any restriction in the system will reduce efficiancy of the pump. But stock LS1 heads are really good right out of the box.

 

Yeah if i still had them...

 

aaaw..

 

"I wont argue, but maybe you missed the GM High-Tech performance article where they did an LS6 HEADS ONLY swap and netted 41 hp (at the rear wheels).

Also, a good friend of mine installed mti 2.5 heads and saw 34 hp increase with stock cam."

wow

hard to argue with dyno number (from a mag maybe )....but i'm really surprised.

hard to imagine the gain would be that much.

i'm curious how the power curve looked on the low and mid range. like i said, you can increase the intake runner to boost high end performance (high peak dyno numbers tend to sell products) but it's power under the curve that wins races.

 

Jeff, if you read the entire article you will notice that the car already had some mods done to it prior to the heads install, here's the list...LT's, y-pipe,ASP pulley,ported TB,TSP cam 231/237-598/595, TSP pushrods and comp cams 918 srings.... hardly stock! Pat yourself on the back, he needs a cam for those heads to really shine!

 

now that's pretty believable...

hm...similar cam to my setup...hope i can pick up 41hp with heads...would put me damn close to my 450rwhp goal.