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800hp 446in. N/A whats missing ?

 
andrelossem
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Posted: 04/09/13 08:31 PM

My engine will be 446 in. N/A I'm hoping to get as close to 800hp as possible!! so whats missing?  
I'm getting LS7 block, I already have Eagle 4.175 crank( rod journal were turned down) and 6.125 rods. Looking for 11.5 to 11.8 comp. This will use Hyd. roller setup with no more than 6800 to 7000 rpm's.Open for any intake, besides sheet metal.What heads would work best, looking at TFS 245-265 / WCCH Brodix LS7 and Mast PXR inline valve heads. Also is 680 to 690 lift on the cam going to collapse a good lifter, like Moral or Lunati, what problems am to expect I've already found springs. Billet cams say that they can make me a cam in that lift range that won't tear up valvetrain. What am I to do next?  

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Scott Parker
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Joined: 12/07
Posted: 04/10/13 07:56 AM

What gas do you plan on using? We made 720 hp with ported LS7 heads, hydraulic roller (around 7000rpm), and 451cid.

http://www.gmhightechperformance.com/tech/lsx_engine/1008gmhtp_lsx_dyno_three_different_intakes/

800hp is a tall order, especially with those cubes, pump gas friendly compression, and a hydraulic roller. To keep with a cast or composite intake you'll need to stick with an LS7 style head like the Brodix, Mast or All Pro. All Pro, Mast, and Chevrolet Performance have higher-flowing race style heads with a matching cast intake, but they may be too large for your combo.  

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PaulHuryk
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Posted: 04/11/13 06:25 AM

It may be extremely hard for you to make 800hp at or below below 7000rpms when (as Scott said above), the GMHTP 441 made only 720hp at 7000rpm. While I'm sure you could pick up 20 to 40 hp more than what they made, you will probably need more revs to push that level of power out. There is only so many hp an engine can make without adding boost, volumetric efficiency, revs, or cubic inches and still function on pump gas - it's a trade off of sorts.  

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andrelossem
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Posted: 04/11/13 10:28 AM

Some people don't think it 's possible but I talked to Mr. Mamo about a month ago and he said to look at his build 650hp 454 and and to change intake to holley ram and I would get 670 to 675hp. I just hate the idea of getting some heads that every one has, I just may get TFS 245 with Nos exh. heads and send them to Mamo and have him to work them to maybe 260cc and be done with it. Also get Holley ram air, cause Mast are 4200 with all the parts and 1800 bucks for intake.I'll just see what this does.Thanks again!!!!! I'll see if Mamo will do 245 TFS heads and port Holley ram intake I could also get Titanum valves with the money I have left over.  

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andrelossem
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Posts: 6
Joined: 04/13
Posted: 04/11/13 03:07 PM

TONY MAMO: engine build 748 hp
I think I posted some of the bits and details in the first post I made but the quick rundown is:
-Bore and stroke 4.186 / 4.125 (exactly 453.9 CID) 11.75 CR
-LS2 aluminum block with Darton dry sleeve liners
-"V2" AFR 245's (with lightweight hollow stem intake valves and some Mamo romance work).Ported to 255 cc's
-One of my ported 102 FAST intakes of course
-Comp 251/254....114 LSA....661/624 lift (1.8 intake rocker)
-Callies rotating assy (Dragonslayer crank/Compstar rod)
-Wiseco custom pistons / Total seal rings (non gapless)
-ATI dampener
-Cloyes single roller hex adjust timing set
-A ported OEM pump (I start with a better GM casting and port the internals for more flow)
-Comp limited travel hydraulic lifters (note you have to be a little more fussy with pushrod length and preload).
-Manton 3/8 pushrods (.095 wall tube) and note the 245's were designed to accept the larger pushrods right from the factory.
-New design Yella Terra 10mm Ultralite rockers (a beefier version of their current successful line of rockers but you must drill and tap your rocker stud holes larger to 10mm (versus 8mm stock).  

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OVRKILL
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Posted: 04/13/13 02:39 AM

You're gonna need  more cubes and more rpm.   Why not a sheet metal intake?  Two words.....John Marcella.  What it's going in.....lol, not relevant just a curious gear head.

I'm running a RHS 460 with a Kinsler ITB, Mast Inline heads and a "donated" hyd grind from Crane in the .670 range that got pretty close to 800 at 7k.....we'll see how much BS was in the engine dyno # when it hits the rollers, but it looks cool as hell.

Tony's build is def stout but for all practical purposes is a blue printed piece with extensive efforts that the average guy couldn't afford.  

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OVRKILL
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Posted: 04/13/13 02:39 AM

*double post*. Fail.....  

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andrelossem
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Posted: 04/14/13 11:18 PM

Well I got TFS 245's with nos exh. now let's talk about maybe 730hp with a ported Holley Ram Air intake is this possible with say 253/257 cam with 670 to 680 lift with 1.8 rocker arms. I may get heads worked over on intake side by Dr.J's cylinder head service any thoughts? Oh yeah, Mr. Overkill I followed your build you gave me the thought of trying to get Nascar #'s for a street engine Thanks for the inspiration. I liked Mast Inline valve heads for 4200 but 1800 for intake killed the deal.I'm hoping with some port work on heads and intake this will be achievable.  

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Scott Parker
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Posted: 04/18/13 09:42 AM

How much are you planning to spend on porting the Holley intake? By the time you spend all the money to have it ported you may not be saving much (if any) money. The Mast intake comes completely ported, it looks like a mirror in there. I'd figure out what is going to be best for your combination. Intakes are a funny thing. More airflow and plenum volume isn't always what you need (check out our April issue to see what I mean).

I believe that 800hp is possible on pump gas, but probably not with the parts you have selected (unless you want to get creative with your dyno procedure). But anything over 700hp is still pretty awesome for a street motor. Have you thought about running E85? You'd be able to run more compression and/or timing. Just a thought...  

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andrelossem
I love my Chevy Chevette!
Posts: 6
Joined: 04/13
Posted: 04/18/13 09:43 PM

I've talked to Brian Tooley and he said follow his build to the T. 704 hp with TFS 245's. I would think with Mast or Holley ram intake 750hp is possible
Brian's build:
LS7 block 4.125 bore 4.250 stroke Cam 251 267 625/625 11.3 comp.
My build ERl: 4.185 bore 4.175 stroke Cam 255 267 683/683 11.8 comp.  

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andrelossem
I love my Chevy Chevette!
Posts: 6
Joined: 04/13
Posted: 07/06/13 02:10 PM

Now looking at Mast inline head & LSX DR raw port heads ported by Mr. Greg Good he would port 1 intake and exhaust runner and then I could get the others CnC'd.Any thoughts.I'm going to have a Comp ratio of 12.0  

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