I just bought a pair of bare stage 2 ported heads (Was a stock lt1 alum head.). The only thing it comes with is stock valves. I still have to get the write up (forgot to write it down). But they have been ported and a 5 angle job, ported to handle 500 Hp.

So they are bare and need to assemble, what are all the parts I need and recommendations. I have a lingenfilter performance book and a how to rebuild a Lt1 book so that will help. I just wanna get some ideas So far I have.

26918-16 springs
774-16 retainers
4705-16 spring seats
I not sure on what locks to go with.
Whats a good 1.6 rocker and stud?
Pushrods which to go with?
Lifters?
Should I change the valves anyway?

My goal is to be around 400rwhp so something to hold in this application area.
Thanks

 

what cam are you using? the springs need to be matched to the cam.

 

Im looking into the XFI Xtreme Comp cam right now specs are
Part number 249-07-467-8
280/288 .576.570
But Im thinking it may rev to high for a stock bottom end?

I might go with the LPE 219/219? maybe K-Motion K-800 springs for this cam

If some one could give me cam to springs 101 that would be great.

Any inputs and suggestions for a good cam would be great.
I'm sticking with a stock bottom head so keep it in mine. This is a toy and isn't driven daily.

 

I don't think ported with stock LT1 valve is going to give you 500 hp. You might want to make sure what kind of valve came with it.

The bigger the cam that you go with, the bigger the stall and gears will be required.

Make sure you match your heads, cam, stall, and gears togather, or it will not be too fun to drive.

 

As far as the parts go & as mentioned the valve springs must be matched to the cam. You should be able to get the proper springs, retainers & keepers from the cam manufacturer for the heads you are using. In addition you will need spring seats for the alloy heads.

A note about retainers, they come in different step heights to help get the proper valve spring assembled height. Get the ones the cam co recomends. You will understand more about this area as you read on.

As far as head assembly goes this area is best left to the pros. Its important to know the actual valve lift your new cam gives which includes the rocker arm ratio & its extremely important to check the assembly for valve spring coil bind. If you get coil bind you will bend pushrods & possibly damage the cam lobes. If its a flat tappet cam it will definately wipe out the cam lobes.

The assembly: after the valve & seat resurfacing a valve is placed in the head, install a spring seat, put a valve spring mic on & install the retainer & keepers. Adjust the mic & take a reading. This is the assembled valve spring height. Check the measurement against the chart that came with the cam & springs. If the measurement is a bit more than the one the cam co recommends this is a good thing as a valve spring shim can be added under the spring to make up the difference. IF the assembled height is short the spring seats in the head must be machined down so the correct assembled height can be acheived OR a retainer with a higher step can by used (sometimes).

Check all 16 valves in the manner discribed, record the measurement for each valve so the proper valve spring shim can be used or the proper amount can be machined off the head spring seat if the assembled height cannot be obtained with stepped retainers.

If your cam has alot of valve overlap you need to remove the valve springs from one cylinder & install test springs. Install the head, push rods & rockers & adjust the rockers. Turn the engine over slowly & check the valve to piston clearance as the piston reaches TDC on the exhaust stroke to insure the valves will not hit the piston. Some folks use clay on top of the piston for this test I like a dial indicator on the valve end of the rocker arm. Cam advance & retard bushings or keys also effect piston to valve clearance as well as block deck height, piston dome, head gasket thickness & how much material has been removed from the heads if they have been resrufaced (milled).

If you do not have enough valve to piston clearance (I like .080 minimum) you will need to have the pistons fly cut for valve clearance.

 

It looks like its to the point I have to make my cam selection. Ill make decide tonight what I will go with. Im trying to study up and see the perfect match but its hard to select.

 

More info on the heads I bought is:
heads flowed 278-280 at .600 and 258-260 at .550 something like that on the intake and like 180 or so on the exhaust i might have them swapped around and this was done on stock castings with STOCK VALVES.
heads were milled 20 thousandths also and also has 5 angle valve job with professional serdi cutter stock valves were also tapered for valve job

 

Im going with the LPE 219/219 cam. LPE says that its better to use the Titanium Valve Spring Retainers or for my application can I go with the steel?

 

Use steel

 

Thank god cause others were alot of money.

 

From the LPE site they recommend:
Competition Cams 1.460" OD Dual Valve Springs 977-16
Competition Cams Valve Spring Seats 4704-16
Competition Cams Super Lock 740-16 Valve Spring Retainers 740-16

Any inputs or other things I should add to my list?

 

I would use this spring kit for the LPE 219 camshaft, and Ti retainers are included.

https://www.patriot-performance.com/...&cat=52&page=2

 

1.460" OD Outer Spring
1.060" ID Outer Spring
.700" ID
155 @ 1.850" Seat Pressure
420 @ 1.250" Open Pressure
Coil Bind @ 1.195"
Use with 740 Steel Retainers
Use with 730 Titanium Retainers
Use with 4755 Valve Spring shims

those 977s seem awful stiff for a little 219 cam. it would work but the 987 is also used often on the 219. the spring is the same size but with a little lighter pressure. remember you want to use the least amount of pressure and still control the valve. 420lb is making me worry on factory hyd rollers.