Some head/intake/cam questions

[softballnrd27]

I am trying to figure out the differences in heads, can someone please school me or point me in the right direction.
I am currently looking for a LQ4 or LQ9 6.0l to swap into my 85 and I want to know what the stock heads are and what intakes I can use for it. What are cathederal port heads? I want to put an edelbrock intake/elbow on the top end and still utilize the fuel injection. Will this one work? http://www.summitracing.com/parts/EDL-28095/
With this elbow:
http://www.summitracing.com/parts/EDL-3849/

I have been looking at the texas speed magic sticks, should I go with the MS-3, or the MS-4?

[85burb]

if it is an lq4 that would be the right maniflod. Also looks like the right elbo.

[68GMCCustom]

Cathedral port refers to the intake port design and that the area removed at the top of the fairly narrow but tall ports, for the injector to enter the intake path making the intake port have a "cathedral" shape look to it. The other option is the genIV "rectangular" intake port. Excluding the LS7 (cause its by itself in its own group).....the genIII motors (LS1, LS6 LQ4, LQ9, LS2, LM7, etc) have the cathedral port heads....meaning the intake has a cathedral shape to it vs being rectangular or oval. The genIV motors (L92, LS3, LY6, L99, etc) that are 6.0 liters and over... have rectangular port heads.

[softballnrd27]

Thank you for the clarification!! I just want to make sure I have the right parts.

[Big Port Jimmy 6]

Unless you plan to turn the snot out of that 6.0, I would probably Stay away from that Victor. It will move your torque curve up the rpm range. You will need a 2800-3000 stall to get a good launch. And the street manners will suffer. Jay

[softballnrd27]

I do plan to take it to the track and also throw a 100-150 of NOS at it. Is there a better suggestions as far as intake? The FAST units are cool and all but I don't want to spend the $1200 for it.
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[BR3W CITY]

the stock heads on the lq's are a 317 casting if it wasnt mentioned earlier. You can swap out 243's (5.3 heads) to bump compression if you decide to go with the lower compression lq4.

I'm doing a very simililar setup in my 66. stock lq4 with a big cam and some spray. I chose to keep the 317's (unmilled) and leave my compression lower, so I can spray a bit more. Oh, and the only difference between the lq4 and lq9 is the pistons.

If you really want a new manifold you could upgrade to the ls car manifolds, they flow a bit better high up. Or you can get a set of l92 square port heads and swap those one, which will allow you to run the corresponding intakes.

[68GMCCustom]

if you're set on running a carb style intake with fuel rails, an elbow and a throttle body, the LS1 Performer RPM would be a good choice....but plenty of tests have been run with the LS1 Victor Jr. showing it to have better low end then the car EFI intakes.

[Shon]

Originally Posted by softballnrd27

I do plan to take it to the track and also throw a 100-150 of NOS at it. Is there a better suggestions as far as intake? The FAST units are cool and all but I don't want to spend the $1200 for it.
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Where are you looking to buy FAST intakes for $1200!?!?
I have a used FAST 90 w/NW90 for $950 shipped. OR a new 102mm for $840 shipped.
Granted the TB starts at $375 new so that would put it up to $1200.

Which ever way you go, it will be fun!!

[MONTEZ]

Before anyone spent $1200 on a FAST intake for cathedral port heads, I would recommend using that same amount to find low mile set of GEN IV heads and ls3 intake. You should be able to get complete ls3 heads and complete ls3 intake with a TB for $1200 or less. Hell I know a guy who sells complete LS3's for $2.5-$3k....... Anywho the heads and stock ls3 intake will far surpass the power you would get from a FAST intake for the same amount of money. Just sayin.....

[Shon]

Just as an addition to what Montez states.
06 GTO with stock 243s and bolt ons, includeing RRs with 224 cam makes 413 at the wheels. He decides to go to the LS3 heads/FAST 102, LS3 injectors, and TB makes 445 to the wheels. I will try to get the graphs posted but the car is a beast at 3k to 6500 (as high as owner wanted to push it on stock bottom end). LS3 heads were 'done' locally. And owner eventually wants to go with a procharger so the heads were probably hogged out which I would have not done but needless to say, owner is happy with it and I was shocked at the power it makes and HOLDS.

[MONTEZ]

Originally Posted by Shon

Just as an addition to what Montez states.
06 GTO with stock 243s and bolt ons, includeing RRs with 224 cam makes 413 at the wheels. He decides to go to the LS3 heads/FAST 102, LS3 injectors, and TB makes 445 to the wheels. I will try to get the graphs posted but the car is a beast at 3k to 6500 (as high as owner wanted to push it on stock bottom end). LS3 heads were 'done' locally. And owner eventually wants to go with a procharger so the heads were probably hogged out which I would have not done but needless to say, owner is happy with it and I was shocked at the power it makes and HOLDS.

Just out of curiousity, have you guys ever dyno tested the difference between a stock LS3 intake and a FAST intake, with no other changes being done at the same time? I'm just having a hard time justifying paying that much money for a FAST over the stock LS3 intake.

[Shon]

Originally Posted by MONTEZ

Just out of curiousity, have you guy ever dyno tested the difference between a stock LS3 intake and a FAST intake, with no other changes being done at the same time? I'm just having a hard time justifying paying that much money for a FAST over the stock LS3 intake.

I have not and I will check with my buddies to see if they have had that scenario.
What helped was the LS2 intake being so bad and people swapping to FAST but I think GM figured it out and probably fixed those issues.

[softballnrd27]

When I said $1200 I meant the whole package. Intake and throttle body and fuel rails.
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