248/254, .700 lift, 109 LSA

346 cubic inch motor, solid lifters, gigantic valve springs, T&D adjustable rockers, Stage 2 heads, titanium retainers, something around 11.2:1 compression, forged pistons, forged rods, Weiand intake, and a 150hp wet shot over the top.

I need some advice, since I'm usually a "let's kill this here cockroach with a hand grenade" type...

1) Is this thing going to be streetable at all? I'd like to be able to drive it.

2) How often will the valves need to be adjusted?

3) It'll make power up to something like 7400 rpm and peak at 6800 rpm or so. Does a T-56 & Spec Stage 3 ceramic with the heavier syncros and forks have any prayer of standing up to this?

4) Will it be reliable?

5) Will it idle?

A gentleman in the area is going to a different, larger, and even more radical motor, so these parts will be available.

I guess I need some advice. I was thinking that a 232/232, .600, 112 LSA cam was big, but this thing dwarfs it.

 

only a few vendors have gotten the oil issues worked out that appear with high lift solid rollers like that. I would work with one of them. Futral, Thunder Racing, adn MTI are all great folks.

chris

 

I would assume that that issue is directly related to having bushings installed in the lifter bores. Am I correct here?

 

Sounds like fun. I remember reading an old JoeK post about the lifter oiling issue - it starts to become an issue at above .65" lift. My cam is right at .65", so I've had no issues whatsoever with my setup. My lifter bores are not sleeved. With a cam with that lift, you should probably look in to getting the bores sleeved. Chris at Diamond Pistons knows some things about that, you might ask him.

My old cam (242/242 .65/.65 114LSA) idled at 800 RPM no problem. My new cam has more duration on both sides, same lift, on a 109. Should be interesting. Should be running early next month. I don't expect it to idle as smoothly, or as low. If you don't mind a 1000 RPM idle, it may be fine. Better get yourself set up with LS1Edit, it'll take some tweaking, that's for sure.

-Andrew

 

This is looking like a "GO" gents... and OHMYGOD is it going to kick ***.

More input appreciated!

 

When the lobe goes to a smaller base circle due to the amount of lift- This drops the lifter down in the bore. Some have had issues with that. Its not a given, but Joe K stated that in general, anything over ~.650 lift is going to yelid a smaller basecircle.

I would sleeve the bores either way

 

https://ls1tech.com/threads/showflat...true#Post14114


Just gotta know where to look

 

So, G2...

If I can sum this up, Chris at Diamond knows exactly what to do (sleeving the lifter bores), and I should be peachy-keen at .700 lift...

Sound about right?

 

If you get Chris to spec everything out for you, youre good to go! He is excellent to work with to say the least