[clg82]

Just like the title says, i'm getting ready to have a Magnuson 2650R installed on my 2020 ZL1 and got to thinking, how much extra horsepower stock can these engines take? Also how dependable (aside from the oil pump issues) is the LT4 platform when you start throwing extra horsepower at it?

[dfxrte]

I mean this information is plastered all over youtube and these forums.

Originally Posted by clg82

how much extra horsepower stock can these engines take?

??? I guess you mean before you have to change fuel? Valve covers? clutch? It's endless. The best person to ask would be your tuner and his experiences with the mod list you'd bring him.


Unless you're building your car for 1300+ hp I don't think you have anything to worry about. YMMV maybe it blows up at 750whp cus of a shitty tune

[JSH]

The short block can probably handle 1500 crank, at least. But, you're not going to get much from just installing a 2650, maybe 100. Bunch of threads on this topic.

Originally Posted by clg82

Just like the title says, i'm getting ready to have a Magnuson 2650R installed on my 2020 ZL1 and got to thinking, how much extra horsepower stock can these engines take? Also how dependable (aside from the oil pump issues) is the LT4 platform when you start throwing extra horsepower at it?

[Joshinator99]

Originally Posted by JSH

The short block can probably handle 1500 at least. But, you're not going to get much from just installing a 2650, maybe 100. Bunch of threads on this topic.

Generally accepted limit on LT4 short block is in the 1000 WHP range assuming proper fuel and tuning. Even LME’s “Force Induction” shortblocks are only rated for 1300-1400WHP despite the improved thrust bearing, so a stock LT4 shortblock isn’t hanging on at that 1500 HP level.

[ZO6Ted]

Lingenfelter said their fuel system twin turbo setup did mid 1400's crank so I guess it's pretty stout long as you don't get stupid. Fueling and tune is the key.

[Joshinator99]

Originally Posted by ZO6Ted

Lingenfelter said their fuel system twin turbo setup did mid 1400's crank so I guess it's pretty stout long as you don't get stupid. Fueling and tune is the key.

Not a PD blower so less stress on the crank…

And let’s face it, that’s a glory pull on a motor that’s not even in a car. We have no idea how long that engine survived…

[Camaro1973]

Originally Posted by JSH

The short block can probably handle 1500 at least. But, you're not going to get much from just installing a 2650, maybe 100. Bunch of threads on this topic.

LOL @ 1500.

[Camaro1973]

Originally Posted by clg82

Just like the title says, i'm getting ready to have a Magnuson 2650R installed on my 2020 ZL1 and got to thinking, how much extra horsepower stock can these engines take? Also how dependable (aside from the oil pump issues) is the LT4 platform when you start throwing extra horsepower at it?

A safe Bet would be under 1kWHP. With a Blower like a procharger thats making less boost down low (less stress) would be easier on the bottom end. A blower like the 2650 is going to create more torque which is going to stress the components even more.


This also depends on what your definition of max power it can handle. Handle, and handle with somewhat decent life are 2 different things.


You can probably go over 1k WHP on the bottom end, but it's just a ticking time bomb at that point. Most reputable shops that don't like to blow up cars like to stay around like 850rwp limit so you can actually drive it and have it last as close to stock as possible.



Also around 900whp the trans starts becoming an issue and that should be rebuilt as well.

[Schlok]

The amount of power you can (want to) make depends mostly on your budget. I assume most of us run out of money to do this before we hit the max capability of this engine. High HP builds require an extensive list of mods (obviously) and this becomes a really deep rabbit hole where traction starts to become the biggest issue. Very serious 2650 builds done by very reputable companies will eclipse 30k for an out the door price...

Clearly the posts above are by some on here with some NICE builds and making really, really good power. That 1k HP number seems to be the magic 'limit' before superchargers start to look less appealing than TT.

[Evansa22]

Originally Posted by Joshinator99

Generally accepted limit on LT4 short block is in the 1000 WHP range assuming proper fuel and tuning. Even LME’s “Force Induction” shortblocks are only rated for 1300-1400WHP despite the improved thrust bearing, so a stock LT4 shortblock isn’t hanging on at that 1500 HP level.

Originally Posted by Camaro1973

A safe Bet would be under 1kWHP. With a Blower like a procharger thats making less boost down low (less stress) would be easier on the bottom end. A blower like the 2650 is going to create more torque which is going to stress the components even more.


This also depends on what your definition of max power it can handle. Handle, and handle with somewhat decent life are 2 different things.


You can probably go over 1k WHP on the bottom end, but it's just a ticking time bomb at that point. Most reputable shops that don't like to blow up cars like to stay around like 850rwp limit so you can actually drive it and have it last as close to stock as possible.



Also around 900whp the trans starts becoming an issue and that should be rebuilt as well.

My tuner said pretty much the same, doesn't like to go more than 950-1k max whp on stock block

[radz28]

I think CSP has said they don't like taking stock LT4-short blocks past something like 900-950 because of the half-thrust bearing.

Not suggesting that these examples are much more than hero runs, but I think it was Katech or Livernois or someone out there push a stock LT5 long block (E85 and fueling mods') past like 1400 with TTs. If we're talking about hero runs, Engine Masters took a bone stock 6.0 short block, with opened-up rings, to over 1500 without breaking.

Like has already been said - this question is kinda' loaded. The "?safe?" bet is probably around 900-WHP. That's what most of the big shops seem to be pushing out of their doors, depending on combination.

[JSH]

I was thinking of KaTech's article a few years ago saying they could make 1200 crank with the 2650, and also thinking that some other shop has probably made more..

Originally Posted by Camaro1973

LOL @ 1500.

[KingLT1]

It depends on the power adder. The big prochargers and PD units tend to beat the snot out of the crankshaft...and with that shitty half thrust bearing design anything over 850whp can be suspect to failure. Some of that will depend on tuning...if you keep the timing down in the mid range peak tq area to reduce torque on the hit, you can likely take them further. Turbo cars will go further since there is less parasitic pumping loss and nothing pulling on the crank. That is likely how LPE got 1400hp out of their SBE TT LT4 on a engine dyno.

[Camaro1973]

Originally Posted by radz28

I think CSP has said they don't like taking stock LT4-short blocks past something like 900-950 because of the half-thrust bearing.

Not suggesting that these examples are much more than hero runs, but I think it was Katech or Livernois or someone out there push a stock LT5 long block (E85 and fueling mods') past like 1400 with TTs. If we're talking about hero runs, Engine Masters took a bone stock 6.0 short block, with opened-up rings, to over 1500 without breaking.

Like has already been said - this question is kinda' loaded. The "?safe?" bet is probably around 900-WHP. That's what most of the big shops seem to be pushing out of their doors, depending on combination.

Yeah for a street car that you want to last for many miles, best to keep under 900whp. After I add my chiller and race gas tune I’m trying for 850 which should be doable. Still on 14-15psi. Trying to drop 2 tenths lol