lt4 vs built lt1
What do you consider a "built" LT4?
Typically when people "build" a motor, they replace performance parts with better performance parts. The LT4 has better flowing heads, roller rockers, cam, etc., yes, but MOST people opt to "build the motor" by having them ported, replace the cam, increase the displacement, etc. A built LT1 is typically going to be the same damn thing.
You are making a moot point.
What do you consider a "built" lt4?
Typically when people "build" a motor, they replace performance parts with better performance parts. The lt4 has better flowing heads, roller rockers, cam, etc., yes, but most people opt to "build the motor" by having them ported, replace the cam, increase the displacement, etc. A built lt1 is typically going to be the same damn thing.
you are making a moot point.
All about perspective, he makes a car run 10s with unported heads and intake and I think about 360ci max, rpms are a big part of that equasion.
You rev high enough and LT4s might be a good choice, for the rpms we turn with street stock shortblocks though the LT4s don't seem to work as well in reality as they do in the bench race.
. I totally agree, but it is difficult for an average guy to successfully build the proper foundation for a powerful, well matched, high rpm LT1. Not completely their fault though, especially with all the misinformation floating around. The LT1 was never an rpm screamer of a base to start with anyway The first problem the stock bottom end. Many people make it worst by getting too large cams without building the bottom end and then limiting themselves to ~6300 rpm because of that. Then they have to either run crappy times, spin it higher and risk failure, or change the cam.
The second hurdle is that huge POS computer we are stuck with that doesnt like much over 6900(I think 6955 is the official limit for ODBIs??). Most are too cheap or too intimidated to step up to an aftermarket PCM to spin their built bottom ends to the higher rpms they can stand, and they leave power and ET potential on the table.
Thheeennn, you have to deal with the very expensive and fine-tuned valvetrain needed to reliably turn those kind of rpms. It is hard for all but the most die hard and serious builders to justify the price difference in those exotic parts when compared to the "norm" parts, for example mainstream dual springs and steel retainers for a fraction of the cost.
Personally, I would rather take my time and save my money to build a strong bottom end to support my goals, the best heads I can afford, and the valvetrain to keep it all stable...then spin it till is stops making power without having to worry about rpm limits. Its an expensive hobby to do right, no doubt about that, but yet we all still keep throwing cash at these old obsolete cars
Honestly, I would love to see what someone like Gizmo could do with an LT1 if he just built one car ignoring the SE limitations he has been following - just an all out, nasty, big headed, single plain and solid roller NA 396 or something

Sorry for the novel everyone
. The Best V8 Stories One Small Block at Time
What is SE limitation?
What is needed for a valvetrain to rev up over 6K?
How high could an LT1 rev with the right valvetrain?
what/who makes aftermarket pcm's?
Stock Eliminator motors have to run stock rockers.
The LS1 has PM rods.
The LT1 has PM rods.
The LS1 has Hyper. pistons.
The LT1 has Hyper. pistons.
The Lt1 has a bigger bore/shorter stroke than the LS1.
The LT1 heads are not even close to the LS1 heads.
The LT4 heads are better than the LT1 heads.
I guess that it was this statement that got my attention....
Do what best fits you. You didn't state why the motor is currently out of your car. Are you planning to freshen it? I have a thread on here where we did a budget LT1 (stock internals) that you might want to check out. It will eventually get a cam swap too.
Good Luck with your project,
Daren
Just an observation,
Daren



