Generation IV External Engine - Which top end setup 450CID: LSXRT & LS3 heads OR GMPP & LS7 heads?

Out of everything, the biggest issues that has been burning my brain is what to do about the top end.

First option:

102 LSXRT intake and WCCHStage 3 LS3 heads?

Yeah I know I will have to cut the cowl and and as for the hood, I have a VFN 4" cowl Ram Air hood.

Second option:

GMPP intake and WCCH Stage 3 Brodix BR7 or PRC LS7 285cc heads?


Head vs head, I know the LS7 is the winner, but the GMPP and LSX intake is crap! I was wondering if the use of the LSXRT would make up for the lost performance of the LS7 setup.

Or if you have other options that can be considered, like AFR 245s or TF, please explain.

** If you have a Muilt-Vote or if you vote for OTHER, please explain your reason.



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whats the price comparison on the PRC's vs the BR7's?

I think a set of stock 5.3 heads will be good for you. For me, Richard's Brodix heads rule...:burn:

whats the price comparison on the PRC's vs the BR7's?

From talking to Rich @ WCCH, the Brodix are about $500 more than the PRC heads.

I think a set of stock 5.3 heads will be good for you. For me, Richard's Brodix heads rule...:burn:

This was my thoughts exactly... 5.3 all the way!!! lol :P

It never ends Bro! Now that I've decided to go the LS7 route, I then get into a conversation that all the intakes SUCK and can't keep up with the heads, that is of course, unless it's a $3000 fabbed intake. So now I need to take into account the intake and if I'm just throwing away money on a set of LS7 heads or if I'm better off with the LS3 because of better intake options.

Sure I could get the LS7 heads that WOULD out preform the LS3 heads (head to head), but since it's the intake that kills any real potential of the LS7s, does that mean the LS3, with a 102 LSXRT intake, will preform just as good, if not better, than the LS7 with a crap intake... and on the cheap(er).

I don't care what the LSXRT looks like or if I need to cut the cowl... If it performs better with the LS3 (or just as good) vs the LS7 then it's a WIN in my book! Now if they made a LSXRT for the LS7s then I think this would be a moot point since the RT out preforms the R hands down. Would it allow the LS7 to reach their full potential, I doubt it, but I sure it will open that gap between the LS3 and LS7 vs cost/HP that much more to make a definitive decision.

May have a killer WCCH Stage 3 L92/VA Speed modified FAST setup for sale in a few months. :secret2:

Is this the setup we talked about? I think your heads are milled too much for what I need. I was wanting a 70cc+ head.

Is this the setup we talked about? I think your heads are milled too much for what I need. I was wanting a 70cc+ head.

Mine are 65cc. Add some dish to the pistons.

Mine are 65cc. Add some dish to the pistons.


That's the problem... With my stroke being 4.125 and rods at 6.125 it pushes the crown too far up into the head of the piston and leaves VERY little meat for dishing.

With the Stage 2 LS3 heads I had from Rich, they were 67cc and I would have needed a -17 dish for the CC I wanted (10.5:1). That coupled with the thin land ring made for a very worrisome piston. Vic at Wiseco suggested a head with a larger cc chamber as did Mike from CP.

Just curious...why such low compression? 91 octane? Are you planning to boost?

LS7 4500 EFI

• CAD designed and Super Flow flow bench tested
• Fully CNC machined, fully ported and hand finished
• Purpose built racing intakes maximize intake port velocity and airflow

P/N 501-008

Retail $ 1,749.99

Just curious...why such low compression? 91 octane? Are you planning to boost?

Well I'm thinking more on the lines of 11.5:1, but I just want plenty of room if I hit the sauce.

LS7 4500 EFI

• CAD designed and Super Flow flow bench tested
• Fully CNC machined, fully ported and hand finished
• Purpose built racing intakes maximize intake port velocity and airflow

P/N 501-008

Retail $ 1,749.99

Is that a Cary intake? I would love to have it, but it's so dame $$$! By the time you get the intake, TB and Rails, you deep into the $2k range. I know you got to pay to play, but it still hurt to shell out that kind of cheese for an intake setup.

I voted "other" because unless FAST has something new the LSXRT intake is for cathedral port heads not the LS3/L92 rectangle ports.

I voted "other" because unless FAST has something new the LSXRT intake is for cathedral port heads not the LS3/L92 rectangle ports.

WTF!? The LSXRT is not made for the LS3 heads? It's the truck intake I thought it was made for the l92 heads,,,, what's the point then!!!?? :bang: :rolleyes:

Sounds like a nice excuse to me - " But Honey I had to buy the Mamofied AFR 245 heads to go with the LSXRT intake I already have"

Damn it! This whole time I thought the RT was made for the LS3/L92 since it was a truck intake and I JUST NOW realize it for the blow ass Cathedral heads.... WHATS THE POINT!!? Talk about reading comprehension for the loss on my ass!!!

If FAST is going to make a TRUCK intake that suppose to be for PERFORMANCE then why the hell not make it for the L92... There are 4 billion types of intakes for the 317s and little for the L92, which it the REAL performer out of the 2 TRUCK heads... ehhh... some companies :bang: :rolleyes:

This won't do me ANY good on my 450 stroker... damn I'm pissed :bang:

Sounds like a nice excuse to me - " But Honey I had to buy the Mamofied AFR 245 heads to go with the LSXRT intake I already have"

This is one thing I need to start looking into I guess... How do the A/M cathedral heads stack up when compared to the LS3 or LS7 heads? I just always thought that they were "better" cathedral heads, but still not as good as a WCCH Stage 3 LS3 or Brodix or PRC LS7 head. How do the AFR245 fair against the fore mentioned heads?

And IIRC, TSP talked me out of going with the AFR 245 for the PRC LS7 285cc heads when I asked so there has to be a reason. Then again... the AFR is a 245 and the PRC is a 285 :rolleyes:

I guess there's no way to modify the poll options...

Lots of differences between the two, which one is better all depends on your goals. Is this for a DD or track queen? Will it be FI or large NOS shot? What is your budget?

For comparison: WKMCD put down 577rwhp with his 427/WCCH stage 3 L92s.
Pat G put down 500+ with his 364/AFR 230V2s. Both claim to have "mild" cams.

So no one has any other input?!

So no one has any other input?!

You're right, there's no plastic intake that can feed the killer heads we have today....to their max potential, not even close. Get a ported LS7 intake, they have made over 600 RWHP many times. Then save for a sheet metal...........Marcella.

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im running LS7 heads with the fast 102 keeping with the somewhat stockish look and if i put the engine cover on you cant tell and still think its the 5.7L LS1 yet its making around 650rwhp now.

if its out of the bonnet drag car marcella high rise with twin 2000cfm wilson throttle bodies its proven it makes HP also now aftermarket heads are awesome cant go past some mozez or edelbrock we flow benched mozez at 420cfm and edelbrock at 460cfm. flow number mean shit but yeah they outflowed em.

I take it you're from the UK... bonnet ;)

What Edelbrock was giving you 460cfm!? I didn't think the TFS 265cc flowed that well...!

lol... I also see that you're into bodybuild... I was just finalizing my shopping list prior to seeing your post, lol... "wink"

http://www.edelbrock.com/automotive_new/mc/cylheads/chevy/ls-r_victor.shtml

these are raw you need to have then ported and chambers need finishing etc etc, bare head basically.

This is the set up im talking about, this is with mast mozez heads:

http://www.youtube.com/watch?v=r0oodHrDAfc

here is its best time, near full weight GTO here too 4000lbs:

http://www.youtube.com/watch?v=QA-uszLNcsU

but i have seen this type of set up in a ute with the edelbrock heads run 7.2 not sure on the weight though it is lighter than the GTO.

Ahhh... forgot about these.... yeah these turn into $8000 heads real quick once all is said and done, lol...

Ahhh... forgot about these.... yeah these turn into $8000 heads real quick once all is said and done, lol...

you want the best you pay for what you get.
but hey next year there will be something better and the year after that too.

you want the best you pay for what you get.
but hey next year there will be something better and the year after that too.

Can those Edlebrock heads be used on a 100% street car set-up? maybe with a sheet metal intake so it'll fit under the factory hood.

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As you guys know the PRC LS7 heads have been proven winners for as long as they've been out. The PRC casting has powered so many 600+rwhp LS7's it'd be hard to count!

The PRC new LS7 casting is a much thicker & tweaked version of a LS7 head with thicker decks, thicker spring pockets, 6 bolts, etc.

We priced them very reasonable & offer a hollow stem valve configuration that will allow for the heads to be very reasonably priced!

One thing you might consider if your wanting a nice LS7 intake is the Performance Inductions intake. It likes RPM, but compared to a GM intake manifold it seems to perform way better. :) :)

hope this helps.

Can those Edlebrock heads be used on a 100% street car set-up? maybe with a sheet metal intake so it'll fit under the factory hood.

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yeah of course you will need a custom sheet metal intake to match up to it no reason why it cant fit under the bonnet. these heads make peak HP around the 950" lift.

I don't know how streetable it will be, but it will make power.

If FAST is going to make a TRUCK intake that suppose to be for PERFORMANCE then why the hell not make it for the L92... There are 4 billion types of intakes for the 317s and little for the L92, which it the REAL performer out of the 2 TRUCK heads... ehhh... some companies :


Tha answer to me seems simple; The point is there are cathedral port trucks from 1999-present. The L92s came out in 2007 and are very low volume even in those few years. It only makes good sense to start with the heads that take up 99.9% of the market. Plus think about all the older Camaros & Chevelles with LS swaps, most have cathedral ports and have room under the hood......

Why dont you jsut run the LSXR designed for L92s, but the car design? If you willing to cut the firewall up, you should be able to swap to the car style intake. Its a lot less work.

I guess there's no way to modify the poll options...I can, what would you like it changed to? PM me.

As you guys know the PRC LS7 heads have been proven winners for as long as they've been out. The PRC casting has powered so many 600+rwhp LS7's it'd be hard to count!

The PRC new LS7 casting is a much thicker & tweaked version of a LS7 head with thicker decks, thicker spring pockets, 6 bolts, etc.

We priced them very reasonable & offer a hollow stem valve configuration that will allow for the heads to be very reasonably priced!

One thing you might consider if your wanting a nice LS7 intake is the Performance Inductions intake. It likes RPM, but compared to a GM intake manifold it seems to perform way better. :) :)

hope this helps.

Are you taking about the OEM or the PRC castings?

I'm tossed between your heads(PRC castings) and the Brodix BR7s with Rich's port work. The thing is, the Brodix can be picked up for $1500 with a Brodix CNC, then once the cash has been replenished, I could the send them off to WCCH for the Stg 3.

As for the intake you talking about, is that the Cary intake? If so, I would LOVE to have it, but it's too rich for my blood right now. A great value for what you get, but none the less too much for my budget.

How do you think your heads would preform with the GMPP that's been gasket matched?

Tha answer to me seems simple; The point is there are cathedral port trucks from 1999-present. The L92s came out in 2007 and are very low volume even in those few years. It only makes good sense to start with the heads that take up 99.9% of the market. Plus think about all the older Camaros & Chevelles with LS swaps, most have cathedral ports and have room under the hood......

Why dont you jsut run the LSXR designed for L92s, but the car design? If you willing to cut the firewall up, you should be able to swap to the car style intake. Its a lot less work.

I can, what would you like it changed to? PM me.

Yeah I know, it's a number's game, but as popular as the LS3/L92 heads have become, you'd think there would be more R&D and A/M for them by now.

The reason I was wanting to run the RT was due to the additional performance it offered over the R version. And I was wondering if that additional boost from the RT with L92/LS3 setup would have preformed as well as the LS7 heads mated to the crap ass GMPP.

If you could, please change out the 102 LSXRT & WCCH Stage 3 LS3 Heads to
102 LSXR & WCCH Stage 3 LS3 Heads...basically just omit the "T" so no one gets confused... as if it really matters at this point since the thread is over 2 weeks old, lol... Thanks Sweets!

yeah of course you will need a custom sheet metal intake to match up to it no reason why it cant fit under the bonnet. these heads make peak HP around the 950" lift.

I don't know how streetable it will be, but it will make power.

So for a street car...would those heads be kind of a waste at .700 lift.???

.950 lift is way too much for a street driven car I would think.......longevity and reliability would be decreased heavily.

.

How about the new Holly high rise for the rectangle port 3's and 92's. You will have to cut the hood but who cares when you can have the tunnel ram look. LOL . Seriously 2 plate TB's on top of it would be reto cool. Or just go the front mounted T. body look.

I like your last idea with the plastic 102 painted and all the engine covers on it . Its just a cammed stock engine.

What about this ?

VICTOR JR. L76/L92
FOR LS Series GEN IV ENGINES WITH L92 HEADS (3500-8000 rpm)
Designed for Gen IV LS engines equipped with L92 cylinder heads, this manifold is intended for EFI racing applications operating between 3,500 - 7,500 rpm. This manifold uses a standard square-bore carb flange that is compatible with both Edelbrock EFI intake elbows and throttle body or four-barrel throttle bodies. L92 heads are only compatible with a 4.00" and larger bore diameters; smaller bores (including most 5.7L blocks) will require valve reliefs cut into the block. Available for carbureted and EFI applications; EFI manifold #28455 has additional bosses and machining that allow for the use of fuel injectors when combined with the #3638 fuel rail kit.

I thought that Edelbrock released a Super Vic for the rectangle heads last year. Thats the way I would go.

The Vic Jr and WCCH Stg 3 L92 heads were my original idea. In fact, I have a brand new Vic Jr intake and a Accel 4150 1350cfm TB, I even got the intake powder coated, which cost me $300 for a custom 3 stage powder coating.

I found out Friday that I might not get Financial Aid for next semester so I might be paying out of pocket and if that's the case, no Brodix or PRC LS7 heads. :(

I think I'm just going to stick with the L92s just to cover my ass and not stress my budget.

DAMN I hate being broke!

Oh and as far as I know, There's no Super Vic for the L92/LS3 heads :rolleyes:

Did GM ever make these pn19244034. It might be worth a try on a LS3.