Hi Guys & Gals

I am thinking out building a reasonably high reving(6800-7000rpm) 346ci motor for some entry level curcuit racing & general curcuit fun,
So high lift cam & sustained high revs

What are the option for light weight & strong components & has anyone got ball park $$

Thinking of running Comp R filters

So what:
Push rods
Rockers
retainers
springs
Valves

Is good alternatives to Ti components

 

have heard bad things about comp R lifters but not sure about them. And if price is not option a good choice for rocker arms would be the jesel shaft mounted rocker arms.

 

I would get some chrome molly push rods from anyone of the big name cam places CompCam, CraneCam etc, depends on the size of your cam you will either get some CompCam 918 springs good for up to 600 lift, or the dual springs. and if you want light weight I would definently get some titanium retainers too. Keep in mind that the LS6 ZO6 motors has the lighter weight valves in them too, and you can get a set of stock LS6 heads farely cheap these days fully assembled too.

 

Don't skimp on the timing chain and if you are going to do sustained high RPM, get the GMPP timing chain damper. Personally for that type of use I would get the Katech timing chain (JWIS) that they used on the C5R.

 

As far as the comp r lifters go, some have had succes others have had catastrophes. My suggestion to you would be to do a search regarding these lifters and then make your own decision.

edit: And BTW, I have a new set comming to me soon, along with some other new items, which were destroyed when the comp r lifter came apart in my properly pre-loaded (used adjustable t&d shaft rockers) motor. I'll sell them to you for $150 to your door

 

Based on location, you are talking about a Monaro. First, even stock, the LS2 is a lot of power on a race track. So the assumption is you that you ahve a cage, a highend set of Penske, Ohlin, or Bilstein shocks, a collection of Hypercoil or Eibach springs, a collection of anti-roll bars, set of Brembo or equivalent fixed caliper brakes, and a healthy tire budget.

Now, it depends on you budget. Does your class allow button clutches? Tilton and Quartermaster have 5.5" setups for about $1800US including starter.

The rev range you are talking about is not that extreme. For track racing that motor could probably handle a 248-252 cam. Conservatively you could run a 242-246. Both on a 106-107 CL with about 4 deg advance.

After making sure your have a high quality set of valves (Ferrera, Del West, etc.), a Comp Cams 921 will work with the stock diameter, however in a 1.45 there is a better selection. Are you going to a solid lifter cam? It would be one less thing to break. Morel seems to be top here. With Schubeck being a lighterweight alternative at twice the price.

Jesel and T&D both have good shaft rocker systems. The T&D is a few hundred cheaper. The Jesel is a little nicer and sort of the standard for this type of setup.

For a reliable and fast motor in that rev range you will need to pay attention to the crank, rods, and pistons. For the crank, you are probably ok with the stock one with a once over. However the rods should be higher end billet pieces. And be very selective with the pistons. You will need reliefs for the PV with the high lift cam, and enough strength to take the load.

You can gain a bit my reducing overall mass of the rotating assembly. If bore and stroke aren't regulated, you can gain something by using a big more. In oval racing with SBCs rules frequently require a stock bore and stroke. So people build 352s using 400 block 4.155 bores with 327 3.25" cranks. Less rotating mass and better breathing. In addition, Honda 1.88 rod journals or BMW 1.78 rod journals make a lighter crank an lighter rods. With 300M for the rods and 4340 for the crank they are more than strong enough.

Now...if budget is the issue...shocks, brakes and tires will make it much easier to learn. You can actually use fewer revs with no harmful effects. Keeping a 6000-6200 limit will let even a dead stock engine live reasonably. Until you are able to use up the chassis, it may be the best way to go.

 

Lightweight you say:
I will be spinning a 387 ci Ls1 to 8500
Here is what I am running
4.125 bore 3.622 Stroke - $2000 Crank
Carrillo Rods - $2000.00
Titanium Intake Valves - $70 a valve
Lightweight Exhaust Vlave - 24 a Valve
Manton Pushrods - around $24 a pushrod
Jesel Dogbone Lifters - $2200
Jesel Y2K Rockers - $1200

And I am sure more parts I dont remember