Car: 1970 GTO

Weight: 3600lbs +-

Trans: 4L60E

Rear: 12 bolt, 3.73, Detroit Truetrac

Motor: 03' LQ9 with 853 Stage II heads (67cc, Flow chart below), stock pistons, 90mm FAST, 90mm TB, 85mm MAF, Hooker headers (unknown size), electric fans, A/C, power steering, belt driven water pump, etc.


Lift Int. Exh.

.200 128 109
.250 159 127
.300 190 146
.350 219 163
.400 245 173
.450 265 182
.500 282 186
.550 294 191
.600 303 195
.650 290 195
.700 289 195



This will be a daily driven, pump gas car (don't mind 93 Octane). My goal is to be around 450-500 rwhp.


Help me pick a cam!

 

Even though I will be in the minority and you will ignore my input anyway, I would go with a custom grind about 15* or so larger on the intake and exhaust and a relatively tight LSA of about 110* (assuming emissions are not a concern), might even go with a 108 LSA if you are willing to lose some low end (vs 110*) for increased mid/high power.

Something close to 218/224-110 with 4* ground in. Will keep your torque high and relatively low in the powerband (needed for the big car) and should pull to 6300 with little drama. The 4L60E will grenade itself in short order, so budget for a quality build on it. The wide ratios in the tranny will love the torque and there is no need to wind it to the moon to get huge numbers. I favor the 1/8th mile enhancement vs big power 1/4 mile times as I drive 99.9% of the time on the street. Lobes for those durations will give you (w/1.8 rockers) around .56x lift intake and a tad more for the exhaust. Sure, you would leave some power on the table with those heads, but I think it would make a much better street car than increasing the durations more.

 

Moved from Advanced Tech section.

To hit 450-500 rwhp may involve flycutting valve reliefs in your pistons. Starting off with a 67cc chamber is going to put you at a disadvantage starting off. You will basically be running just a little better than a stock head. I think you may need to lower your RWHP expectations.

 

Nope, I was told by TEA that that CC on the chambers will get me enough compression to reach my goals...


Guys are putting 450 to the rear wheels with a cam, intake, and stock heads according to HPP a couple months ago. And that's with a LS6 intake. No reason ported heads and a FAST can't get me there with slighly more compression.

https://ls1tech.com/forums/generation-iii-internal-engine/659509-500-rwhp-6l.html


06SS, thanks. Will take that into consideration. I'm planning on contacting several engine builders/tuners as well.

 

How come all I ever hear is LS1tech has all kinds of experts but so far only one has replied? And he happnes to be totally incorrect!!!!!!

 

I would think very carefully about saying that about Patrick G.. I mean ****.. he only works with COMP CAMS and THUNDER RACING recommending Cams to people..

And to make upwards of 475-500RWHP, you are goin to need a big Cam to do it, cause you certainly do not have the cubes nor the Heads to do it with a medium Cam..and a high-lift Cam requires you to Fly-cut, expecially with the Flat-tops in the LQ9.

Now my setup on the other hand..402ci bottom end with Heads that flow 325/210 @.600 on a 4.000 Bore will get that 500RWHP.. there is alot more Engine there, and alot better Heads..
you might learn something..

 

I would think very carefully about reading my post again. Especially the part where I say 450-500 hp....


If that's the range of acceptability, then it seems to me that 450 will do!


And since there's about 500 people here making 420 with just a cam, I would imagine that PORTED heads, more compression and a FAST 90 would get me another 30hp without many problems....


So once again I ask:



Is there anyone out there that can help me pick a cam?

 

Ummm...
Yea....


Now, I think you should research you project there.. the Fast, maybe 30 Flywheel HP. Good set of Heads..small Chambers are good, but the Pistons have to match them. The LQ9 Bottom End you are using is a good one, you are going to have to do some work to it to get 450+RWHP..you may come close to that, but I would do some internal work to be on the safe side.


Not trying to **** on your project here, you just need to check into some stuff a little more, the source with the highest numbers may not be the correct one..

 

Are you insane?


How is it that LS1 guys with 347 ci are making 420-450 with just a cam and I can't make 30 more hp (say 60 at the flywheel) with more ci, more compression, 300 cfm heads, a FAST 90, and headers?



So much for experts....


Or everyone in the cam only thread is full of ****........

 

then if you have such a problem on here with the input people are telling you then go somewhere else... no1 is forcing you on here to stay and listen. i trust patrick g a lot more then some of the shops guys around. every1 is tryin to help u and ur being a dick. good luck with ur build though! haha

 

oh yeah and also if your an auto that will rob hp and with ur 12 bolt that will rob some too. and can you should on this thread where people are making 450rwhp on cam only with a ls1 motor

 

He just said up there that you had to Fly-cut your Pistons to run a Cam that you will need to get that.. you don't think you need to, so that will limit you Engine right there.
I am willing to bet those LS1 guys have some damn good Heads, probably bigger than yours, and they matched the Bottom End up to run them..
More Compression is a good thing, but you still have to have the Heads to work with it right, and the bottom to match it. More Cubes are good, but you still have to use them right.

And yes I am insane, ****** craaazy man...

 

First off, running an automatic is going to put you at a 20-30 rwhp disadvantage on a chassis dyno compared to a 6 speed car.

Second off, your flow numbers are only slightly better than a stock 243 Z06 head, yet 67 cc is going to give you lower compression. The net effect is going to be around 0-10 rwhp better than a Z06 head.

The FAST intake will be 10-15 rwhp improvement with your application. Again, A4 with average heads with stock compression. Many people who gain more are running manual transmissions and often have better heads.

Cubes: Your 6.0L will give you a 20-25 rwhp advantage over an LS1.

The best cam-only cars run headers with high velocity merge collectors. Does yours?

Look at all the pluses and minuses and basically you'll be in the 420-440 rwhp with the right cam. Increase your compression to more like 11.5:1 and you can expect to see your torque and hp rise another 15-20...getting you very close to your original goal.

Again, running an automatic is the killer here. If you were running a stick, it would be a totally different ball game. Now if you can be happy with the realistic numbers above, then a custom cam can definitely get you there.

 

If you dont want to fly cut and you just want a big cam for big peak numbers and arent looking at getting all the supporting mods, you might want to have a look at the MS4 from Texas Speed, or the VindicatorII from Vengeance racing. Both are great cams and seem to be what people are using these days to get those kinds of numbers.

Altho my personal preference would be to listen to PatrickG, I did and believe me I am pretty happy right now.

 

Someone want to translate that into English for me..........






You guys must all be in denial. Or not very bright.


That's all I have to say on the subject. I'll get my cam, and my build done while accomplishing my goals, and rest assued I'll make sure everyone knows about it....

 

So far, the only thing I'm convinced of from that guy is, the only place he could work is Comp Cams. And that's not a compliment.....


Evidence:


300cfm heads wiith 67cc chambers are "just a little better than a stock head" according to him. Yeah....... Riiiiight......


Flow a stock set of 317's with 72cc chambers and let me know what you come up with.... Then figure out what going from 72cc to 67cc means to a 10.5:1 compression motor...


I guess that makes the FAST 90 **** then.............


OR, he's just wrong.




The honest truth......... If I had made those statements instead of him, everyone on the forum would be jumping on me. But, as with most threads here, this is a popularity contest, and not much else.

 

Anyone who knows what they're talking about is more than welcome to contribute to my thread.


Everyone else is welcome to start their own. Perhaps a thread titled "misinformation given out here" would be appropriate...

 

So your looking for 450-500 rwhp through an auto a4 with a 12 bolt? Honestly I have to agree with everyone else here thats going to be near impossible to do on the stock cubed 6.0 engine and still have some decent driveability. For you to get there your going to need a massive cam in the 240's range on both intake and exhaust, maybe even bigger, plus more compression. As for that article, im not sure what type of dyno they were using but not many guys have hit 450 rwhp cam only without a fast intake and a massive cam in an m6. Id say shoot for a nice cam like the g5x3 or g5x4. You might have to flycut your pistons though. Good luck with the build though and let us know what you choose!

 

Well first off....you are a dumb ***. If you dont think Patrick knows what he is talking about then by all means, you are free to go someplace else and ask for help. You wont get any with that smart *** mouth you've got.

 

Exactly gotta love people who come and ask for help then bash every suggestion and call people idiots...