850hp LT1??
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Teching In
Joined: Jun 2016
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From: Sioux Falls SD
850hp LT1?? I have a block machined to a 383 stroker.. just curious if and or what I need to buy to make it have 850 crank hp.. I have a d1sc and afr 210 heads.. 42# injectors, 58mm throttle body, front mount intercooler kit, factory ported intake, built t56, moser 9", walbro 255.. what cam, crank, pistons etc is everyone using for a high powered lt1?
Off the top of my head, if you're shooting that high, don't be dumb and do an off shelf grind, go custom spec to your application. Also, you're gonna need more fuel then what you've got.
Here's a heavy hitter and well laid out build thread to reference. Around the power level you're wanting as well.
https://ls1tech.com/forums/lt1-lt4-m...mes-charm.html
Here's a heavy hitter and well laid out build thread to reference. Around the power level you're wanting as well.
https://ls1tech.com/forums/lt1-lt4-m...mes-charm.html
Get some custom coated pistons for your specific heads and compression ratio (~$1200-1500 for the set from JE, Diamond, Ross, Mahle, etc). Oliver or Carillo rods ($1500-2000). Some sort of Callies double keyed bbc snout crank (~$2000), custom billet cam ($350). You will need much bigger injectors ~80lb hr. or higher if E85...same with fuel system.
FYI...I am at ~575-600chp NA (will be ~800-850 with a 200-250 shot) with my setup and am running Lunati Pro mod rods, Eagle 4340 crank (one of the older ones that were good), custom diamond pistons, small base circle LE spec solid roller cam.
FYI...I am at ~575-600chp NA (will be ~800-850 with a 200-250 shot) with my setup and am running Lunati Pro mod rods, Eagle 4340 crank (one of the older ones that were good), custom diamond pistons, small base circle LE spec solid roller cam.
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Joined: Jun 2013
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From: Kernersville, NC
Why on earth try to get 850hp out of an LT1? If money is no object then do something with the LS series.
I like my LT1, but no way I'd try those numbers with it. If I'm not mistaken it takes a well sorted out setup to get 700hp out of the old LT...much less 850hp. I just can't see the block not having some kind of issue over time with those numbers.
I like my LT1, but no way I'd try those numbers with it. If I'm not mistaken it takes a well sorted out setup to get 700hp out of the old LT...much less 850hp. I just can't see the block not having some kind of issue over time with those numbers.
I don't think 850 crank hp is too much for a splayed or 4 bolt main lt1, but one recipe nobody seems to try is a 3.48" forged crank instead of going to a 383 with a 3.75" crank. Bigger stroke, more leverage to distort the crank on the mains. A lot of the 1000rwhp LS junkyard guys are using the 5.3 and 4.8 over a 6.0, and maybe 1 reason they survive is the shorter stroke for the stock crank guys. I'd like to see someone use either a stock bore, or only 0.010" over, and stock stroke forged crank, splayed 4 bolt mains and see if it survives better than a 383. Displacement can be overcome with boost.
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You have much to read/learn OP.
42# injectors and a walbro 255??
If you want that power you need to feed it fuel to make it. ID200s, big *** 8AN lines, and either triple 255s/340s, or double -044s, or step up to a large single magnafuel or similar.
42# injectors and a walbro 255??
If you want that power you need to feed it fuel to make it. ID200s, big *** 8AN lines, and either triple 255s/340s, or double -044s, or step up to a large single magnafuel or similar.
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Joined: Feb 2012
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Or buy a 7.0L LS crate motor mod accordingly and have a more reliable safe setup rather than pushing the limit of the LT motor lol.
I applaud the enthusiasm, but seems to be a more efficient way to make that specific power level you want...IF money is no object.
I applaud the enthusiasm, but seems to be a more efficient way to make that specific power level you want...IF money is no object.
850 crank is easy with boost. Its not that much for a boosted SBC.
Note that I didn't say cheap, just easy. You will need a LOT more fuel then what you have(both injectors and pump are way too small, and your lines will need to be replaced), custom cam, quality forged rotating assy, 4-bolt mains and half fill the block, ARP2000 rod bolts (L19s are overkill at 850 since you wont be spinning a million RPMs with a boosted 383, and they are huge and hard to clearance for), and I would change to an easier to tune computer - either a 411 setup or standalone.
Up the boost, up the fuel, and hope your machinist earned his pay.
Note that I didn't say cheap, just easy. You will need a LOT more fuel then what you have(both injectors and pump are way too small, and your lines will need to be replaced), custom cam, quality forged rotating assy, 4-bolt mains and half fill the block, ARP2000 rod bolts (L19s are overkill at 850 since you wont be spinning a million RPMs with a boosted 383, and they are huge and hard to clearance for), and I would change to an easier to tune computer - either a 411 setup or standalone.
Up the boost, up the fuel, and hope your machinist earned his pay.
Shownomercy is probably at 800hp, so he has some good real world LTx experience.
I personally think stock lines, dual I tank pumps, and 80" injectors are more than enough, but bigger is better with a fuel system. I will say, if you run a meth kit, you can pull a ton of fuel out of the tune.
My personal car (LS3 2010 Camaro) makes 703rwhp/762rwtq on 93 octane + meth dual nozzle kit and my 95lb injectors are under 60% duty cycle.
I personally think stock lines, dual I tank pumps, and 80" injectors are more than enough, but bigger is better with a fuel system. I will say, if you run a meth kit, you can pull a ton of fuel out of the tune.
My personal car (LS3 2010 Camaro) makes 703rwhp/762rwtq on 93 octane + meth dual nozzle kit and my 95lb injectors are under 60% duty cycle.
Here is SNM's build thread for more info on what it takes for 850ish HP.
http://www.ls1lt1.com/forum/moderato...lt1-build.html
There are other good build threads on ltxtech.com as well that detail what it takes to support that power level. 850 crank or about 650 wheel can be done fairly easily, I say that compared to 850 wheel hp, as a 4 bolt main (splayed or straight) has held up for quite a few people. Popo has another good build on ltxtech.
http://ltxtech.com/forums/showthread...PO-quot-camaro
http://www.ls1lt1.com/forum/moderato...lt1-build.html
There are other good build threads on ltxtech.com as well that detail what it takes to support that power level. 850 crank or about 650 wheel can be done fairly easily, I say that compared to 850 wheel hp, as a 4 bolt main (splayed or straight) has held up for quite a few people. Popo has another good build on ltxtech.
http://ltxtech.com/forums/showthread...PO-quot-camaro
I would do Lunati forged 3.75 stroke, same 5.7 rods, and je forged pistons at like a -14cc dish. Shoot for like 9.5 to one static compression. Your gonna need a 2nd 255 at least and dual pump hotwire kit from caspers. U might need three pumps in which case id go else where bc for that high of power your best bet is E for fuel, which means more volume required than race gas at a similarly high octane. THen someone who tunes nassty LT1s is always reqd in a build like this. Were prob talking 7k in parts u havent thought of. Stainless braided fuel lines and fittings in -8 or -6AN. Theres a list of stuff. The front suspension needs build with the engine as well as entire rear w drag bar. Least a 6-7 pt roll bar. HIghly rec Corbeaus to run harnesses and they are tall enough to prevent your head from ever hitting the cage. And they are amazing bolstered u in place. Plus for the price, theyre like recaro good.
The details matter with a build like this so if you aren't comfortable or have the time to do the homework, find someone who has spec'd this out. My build may be a reasonable example. I didn't try to reinvent the wheel with my setup but tried to make good choices where possible.
Off the top of my head here goes.
Off the top of my head here goes.
- Max pulley the D1 or perhaps over spin it a touch
- ~9.5:1 SCR if running pump gas (maybe some meth on top)
- Diamond/JE/Wiseco/Etc pistons with the top ring as low as reasonable - 2618 material recommended
- Custom blower cam as wild as you want
- 5.7/5.85 rods will be fine - forged obviously
- Ring set made for boost - conventional set (steel top ring)
- Heads need springs to handle the boost level and work with the cam (have those all spec'd together)
- Block work with 4 bolt mains (splayed recommended) - align honed, studs, confirm correct finish for head gasket material choice - MLS recommended
- Twin 255s with minimum 80lb sticks. Going with more isn't a bad idea.
The details matter with a build like this so if you aren't comfortable or have the time to do the homework, find someone who has spec'd this out. My build may be a reasonable example. I didn't try to reinvent the wheel with my setup but tried to make good choices where possible.
Off the top of my head here goes.
Off the top of my head here goes.
- Max pulley the D1 or perhaps over spin it a touch
- ~9.5:1 SCR if running pump gas (maybe some meth on top)
- Diamond/JE/Wiseco/Etc pistons with the top ring as low as reasonable - 2618 material recommended
- Custom blower cam as wild as you want
- 5.7/5.85 rods will be fine - forged obviously
- Ring set made for boost - conventional set (steel top ring)
- Heads need springs to handle the boost level and work with the cam (have those all spec'd together)
- Block work with 4 bolt mains (splayed recommended) - align honed, studs, confirm correct finish for head gasket material choice - MLS recommended
- Twin 255s with minimum 80lb sticks. Going with more isn't a bad idea.
You're likely gonna have to over spin a d1SC to make that kind of power. It's more f-series blower territory.
As far as people saying to buy a gen 3+ motor, why do you even post?
As far as people saying to buy a gen 3+ motor, why do you even post?
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Joined: Jun 2013
Posts: 853
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From: Kernersville, NC
OP says money is no object and decides to choose a 20+ year old platform that was abandoned by GM after 5-6 years for a truly monster build....and you don't think it's wise to question it?
I like my LT1, as I've owned it for 17+ years...and most likely will until the day I die, but I'm not so blindly loyal to it as ignore the modern tech on a blank check build.
I like my LT1, as I've owned it for 17+ years...and most likely will until the day I die, but I'm not so blindly loyal to it as ignore the modern tech on a blank check build.
Last edited by ACE1252; Nov 3, 2016 at 11:08 PM.
Ugh, one of these guys... Tell that to everyone running SBC and BBC "old platform" builds, the latter of which would stomp an LS. OP asked for info on an LT1.
I'm kind of with Ace here, as depressing as it is, an LTX build now pretty much qualifies as a "dare to be different" build. At 850 hp, you already need to go to a later PCM if you want to find a tuner, and at that point, might as well build a LQ4 or 5.3 with one of the many LS turbo or supercharger kits. A lower goal of 600hp doesn't as much require swapping PCMs and doesn't question the 2 bolt block, but 850 you start to break even on cost or get cheaper going LS.