Cylinder head and intake manifold options...please help

[ls1monza]

I have two v6 engines and wanted to take all of the best parts from both and build one to go in my truck...The question I have is regarding which heads to use. The first choice is a set of ported GM "raised runner" 23 degree heads. They are fresh,complete and ported(essentially all new good parts and ready to go) ...The second choice is the early standard port 23 degree bowtie GM heads....they have been on an engine that Katech built in 1987 and havent been run since 1991. The car was in storage and they are in superb shape(but of course)will need freshening and valve springs at least. My intake manifold choices are a standard port Brodix single plane intake or the ported 2 piece "box ram" currently on the engine with the raised runners (very difficult for rails and injectors).... I ultimately would love to run the brodix intake"better for EFI" on the raised runner heads; but have no clue what is required (if reasonably possible) to make the two mate.....OR...would the gain not be so necessary with turbo for the extra effort and I should just run the standard port heads and intake together? The raised runners flow 306cfm at .600 lift and I would guess the others are in the 240-250 range...Thats a huge difference but turbos have a way of pushing airflow regardless....My goal is roughly 450rwhp(2400lb LUV Truck) on 93 octane.

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

Cmon!!! Nobody has ANY knowledge of what is required to install a standard port intake manifold(like stock Syclone intake) on the "raised runner" heads?! :dunno::dunnoo I need to buy a Syclone just to deserve any response? I AM using SyTy running gear....isn't that worth anything? :roll:

 

[blacktyaffair]

Re: Cylinder head and intake manifold options...please help

Not sure but I think you can weld up the intake manifold to fit the raised runner heads just like you would for vortec heads. What's your handle on luvtruck.com? I'm noluv4u and I have a '79 2wd stepside, yellow of course, that I'll do something with one of these days.

 

[It's just a six]

Re: Cylinder head and intake manifold options...please help

If you are looking to make only 450 HP, use the heads & intake that is easier to fit & standard parts fit.

I am making close to 400 HP to the wheels on a completely stock engine w/25 psi & heads that flow what?
I'll tell you what,, they flow like crap.:rotf:

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

Thats a good idea......and Im not on the LUV boards ..YET!! Thanks for the replies guys. Id hate for the RR heads to go to waste...but someone will buy them....

 

[Buick 6]

Re: Cylinder head and intake manifold options...please help

There is a very good chance that the K Tech heads would be from a 9 to 1 ASA motor and would be larger chamber heads. If they have any numbers stamped in them or you have the complete motor call KT and they can tell you everything you want to know about them.

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

lol.....I tried....Kael is retired and Jason(his son) was 10 years old then.....they have no archive info that far back... The numbers dont cross anywhere....I'll take a pic and post it. Maybe you guys can help....yay!

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

Here you go!! Good luck....and thanks

 

[nallj92]

Re: Cylinder head and intake manifold options...please help

If you really want to make the heads work...
Make some aluminum spacers for the intake and then weld them on the stock syty bottom or get a Edelbock 2111 intake and do the same.

This would raise the intake manifold to align the raised runners to the short runner stock intake. The port sizes would still be a bit off, but with some port work, the transition could be smoothed a bit. Then you would need to fill the front and rear china wall, and also machine for the distributor to fit. Pretty much it would be a lot of work.


If your only looking for 450 WHP, just get a set of vortecs and turn up the boost.

 

[Icarus-54]

Re: Cylinder head and intake manifold options...please help

I have a set of the same heads,they were made for road racing on the 229 and smaller bore.The intake and exhaust ports are very small,they are not raised runner.You have to grind the hell out of them just to get a 195cc intake and a 68cc exh.However a moded SY/TY intake will work fine,but you have to open the heads up to work with a 4.3 as the poirts are smaller than a stock Lb-4 head.They generally came with 2.05/1.60 valves.Save yourself a lot of B.S. and get a set of L-35's or vortecs,you'll get great performance without the work.I have a set of these on my green ty and they work well,but are the worth all the porting?Only if you've nothing else to do and have the right stuff to do it with.I'm retired--I had the time.

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

I have always thought those people at Katech were the gurus of these motors in the 1980s... They built this motor and chose those small heads for it....I havent taken the engine apart yet..but the build sheet suggests 280 cubic inches with a 4.125 bore and a custom Oliver even-fire crank(?)....It DOES have the bowtie symbols on the block,and an external belt driven oil pump with a dry sump tank and oiling system..I dunno.

 

[Icarus-54]

Re: Cylinder head and intake manifold options...please help

Not to mention that these heads have angled plugs and require custom headers

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

Yeah.....I was already planning on building a set of headers....I bought some really cool Stainless steel parts from the guys at ARH.....The factory block engine has alot of great valvetrain parts and I was hoping on using the Hydra-Rev kit and roller cam (from the stock block) in the bowtie block as well....

 

[Icarus-54]

Re: Cylinder head and intake manifold options...please help

factory roller cam will not work on a bow tie block,there is no retaining plate for the cam,you must use a cam button and thrust washer.Which means the nose of the cam must be like a flat tappet small block

 

[ls1monza]

Re: Cylinder head and intake manifold options...please help

Motor number one...(good heads with factory type short block) is on the stand. i pulled the intake off and test fit the standard port intake...whew! the port location isnt too far off but the raised runner heads have a wider bolt configuration. Now I see why the spacers are necessary.