So unfortunately I just sent a rod through my block in my 99 manual trans frc with 50k miles. Im now looking at engine swap ideas… either a tahoe 5.3 or a lq4 6.0. I know both are iron blocks but im drift building the car and I would like it to push around 450-500 and be able to take a bit more beating than the aluminum alternatives. What are the pros/cons of each engine and what do yall recommend? Other suggestions are welcome as well. Tia
What is your total budget for the new engine and upgrades to the rest of the drivetrain? Doing the work yourself or having a shop do it?
I don’t necessarily have a budget (thats a lie because I would 100% lt4 swap it if I could) but probably no more than 10k for everything. I could probably get either engine for 1k then I would do an overhaul and a few power mods but nothing crazy. Like I said 450-500hp. I would be upgrading my clutch as well. I may upgrade my dif but its welded so I should be fine for now. Also all work would be done by me
6.0 will hit those numbers with a cam and normal intake/exhaust mods while a 5.3 will have to work harder and those numbers will be more peaky unless you turbo. Either motor can do it, the 6 liter just doesn't have to work as hard to do it.
6.0 will hit those numbers with a cam and normal intake/exhaust mods while a 5.3 will have to work harder and those numbers will be more peaky unless you turbo. Either motor can do it, the 6 liter just doesn't have to work as hard to do it.
the 6.0 should also bolt right in for the most part no?
I've owned both. Both great engines, trouble free for a gizzion miles.
In stock form they're not that much different, the 6.0 seems to have more umf overall....and weirdly way harder on gas. You can turn an LQ4 into an LQ9 with flat top pistons for a few extra cheap ponies.
If going the 6.0L, get an '01 or newer since '99-'00 have iron heads and a different output flange thickness
Get the new summit LS 427 short block and call it a day. Do a mild build that’s streetable, and with 50,000 miles on the car, it’s probably a keeper. Do it once, do it right, and be done with it.
HCIH, associated upgrades and tune on my 2000 5.7 made 460 at the wheels, which is 500 at the crank.
I'd expect the 6.0 to make what you are looking to do.
Probably well over 500chp to make 460whp. Sounds like a nice motor.I agree with Beast on the Summit setup. Main reason being the LS7 block is not quite as strong as the LS3 block that the Summit 427 is probably built from. The LS7 blocks have very hard, thin sleeves that are somewhat prone to cracking if there's any detonation. They arent too forgiving. Most times if the sleeve cracks, the aluminum block behind the sleeve also cracks, and the block is junk.....
I drove and accelerated my supercharged LS1 through less than 6" of hurricane rain water due to an overflowing storm sewer less than one mile from my home resulting in a hydro-locked engine. Since the C5 is a bottom feeder, it didn't take much and the supercharger took in water like "a hooker snorting cocaine!" (Shop mechanic quote)
As a result, we dropped in a LS3 crate engine and re-engineered the A&A SC with a Stage 1 Texas Speed Centrifrugal CAM and Kooks headers. Car has 660 HP at the wheels and really bridged the gap from the stock LS1 to my C7Z supercharged LT4.
Still waiting for a link on that Summit alloy block 427....
I don’t think the 427 summit block was aluminum. I’m not sure if you’re going to find an aluminum block unless it’s an LS3 block or a used engine from a junkyard. Others can chime in on that.
But seriously, 99.9% of us on these forums are not pro drivers and you will never notice the 100 pounds added to the front end because of an iron short block. A racecar driver that drives LS corvettes might notice the added weight.
