It is possible to do quite well with the old LT platform as it is simply a classic small block. However, producing big #'s reliably it is typically beyond the point of diminishing returns for most guys. While the magic 500rwhp # is commonly discussed, and even predicted, documented cases are quite rare in reality.

This is doable while retaining the standard 23deg layout:
http://www.advancedinduction.com/Dyn...3octA4-SAE.jpg
http://www.advancedinduction.com/Dyn...3octA4-STD.jpg
http://www.advancedinduction.com/Dyn...ullBoltOns.jpg

It is also fairly expensive.

Gizmo is dead on - you need a realistic budget, and to then define some goals/constraints from there. Otherwise, you may end up with a never ending project that exists more in theory online than in reality in your garage.

For reference, whether chassis or engine dynos, they all vary somewhat due to test setup, methodology, calibration, etc. The 383 above managed 650-680 IIRC depending on dyno, fuel, and calibration.

Good luck w/ your project!

 

But according to my dyno calculations I should beat your "stock" car right.

 

Bring it to the Shootout and find out!!

 

what he said come race my 480rwhp car lol.....

 

Convert it back to stock and I have $.65 on it.

 

I agree to a certain point. A mild solid roller (like what I am running) can get away with stud mount rockers and still retain a stable valvetrain, however for what is being discussed as big power in this thread it would be absurd to run anything but shaft mount.

 

Yea numbers are definitely one thing and the track is something entirely different. I really need to get a roll cage in my convertible before I even touch the track with it.

 

So is my motor doomed? 13:1 383 AFR 210's solid roller but no shaft mounts? it has regular stud mount rockers and a stud girdle. This style combo worked on much bigger cams and many more rpm's on our big blocks........

 

Not doomed. Flex is always your enemy. It all depends on how aggresive your cam is and what size studs you are using. Pushrods shouldn't be counted out either.

 

Yea, you don't hear of 3/8"+ pushrods on LT1s, however shaft mounts are a total necessity I'd rather run a big pushrod, light valve, and titanium spring hardware for the cost of shaftmounts, gains per $ are much better.

 

I can't believe how overlooked pushrods are. The crappy ~$80 pushrods most run look like spaghetti at high rpms with any decent spring pressure.

I would guess a pretty big percentage of builds on the site will pick up more power and gain more rpms just by swapping their springs and pushrods.

 

But, in a perfect world, they are one more piece in the puzzle if you are looking for maximum power and reliability. If the rules allow them and you can afford them they are the best choice.

 

Yea I'm not discounting the benefits of shaft mounts, but for the $$$ they're pretty far down on the list! Especially when you consider decreasing valve-side mass will REDUCE rocker stud deflection.

 

In my case I have to run shaft mounts. My valve spacing isn't stock. The intakes are offset. Even with an offset lifter and pushrod cup in the rocker arm, it's not perfectly straight. The intake rocker will have a tendency to slightly turn over a period of time. It's not something I want to chance. I could either spend $1100 on shaft mounts, or spend $350 on stud mounts along with $250 for a special stud girdle, and then a little extra for the offset lifters. In my case it was the best choice. If it were strictly a drag car maybe I would have gone with the stud mounted ones.

 

That also depends on the pushrod length. Some of the solid lifter/link bar style HIPPO lifter bodys are much taller allowing to run a significantly shorter, small diameter pushrod with stud mount rockers.

 

i run a 3/8" pushrod with a very...very...low valve side mass as well as a very light lifter and a jesel shaft system.....no matter which way you slice a stud is going to flex at high rpm and high spring rates/agressive profiles.......flex = power loss and engine damage.......even after two years of beating the snot out of mine 8000+ nearly every time i drove it.....the valve train looked perfect......i put it right back together and its running the same way now.............are shaftmounts necessary with a SR setup.......absolutly not...........would i highly reccomend them in a high rpm more agressive setup absolutly.......i DO NOT think they are a waste of money nor at the bottom of my mod list......durability must be a factor in designing of a valvetrain not just valve control......

 

This is a great example of fact. Shaftmounts being a couple hundred more is a no-brainer for the stability and power gain associated on a SR setup.

Exactly. Mike said it perfectly there. A number of people in this thread have started turning the focus off of the initial discussion on the benefits/gains associated with a shaftmount rocker system and onto the "necessity" of them. No one is saying that you HAVE to run shaftmount. An engine is not going to fail with a decent rocker (and/or girdle setup). I ran a stud girdle on my previous SR 396 and it did work fine. But, it's a fact that it would have gained power and valvetrain stability with a shaftmount setup.

A high HP NA motor is going to cost money. You take shortcuts, you have problems.

Tangible numbers? My mild hydraulic roller motor gained 12rwhp with changing to shaftmounts alone. Certainly a poor "bang for the buck", but that is not what this thread is about. I'll enjoy the extra power and stability.

 

im sure it is whatever comes on the 210 afr's for studs have not looked at them to be honest. cam is a 265 273 @ .050 .650I .631E on a 110LSA

 

Not from what I've seen. I have a set of Comp 888-16's (with the oiling groove) sitting here, along with a pair of Comps with out the oiling groove, and a set of new Crower Maximus HIPPO lifters. All of the solid lifters have the pushrod recessed way down into the lifter body. The pushrod sits maybe 1.5" up from the wheel. The only thing "taller" about these lifters is the attachment arms are extended way up to clear factory roller blocks.