LT1 hp limitations
Thread Starter
Instructor
Joined: Jun 2018
Posts: 236
Likes: 17
From: Stockton California
LT1 hp limitations
So... I’m in the process of building my 94 corvettes LT1, so far MY GOALS were 600rwhp! From what builders I’m contacting they are saying those are the limits of the LT1.
600 didn’t seem like that much to me, what are numbers being produced and what did it take to get there. Budget is around 20k for engine.
600 didn’t seem like that much to me, what are numbers being produced and what did it take to get there. Budget is around 20k for engine.
Melting Slicks
Joined: Mar 2016
Posts: 2,778
Likes: 580
From: Langley BC
Wow, that is a healthy engine budget!
I imagine if you went forced induction the sky is the limit for HP....
This isn't an LT1 but should give you an idea what's possible with some money and forced induction... 1,300HP street car!
http://www.invisibill.net/TT_C4/
Now if you were asking what the limit of the LT1 block is, I'm not sure but with you budget no need to be limited by a stock engine block.
I imagine if you went forced induction the sky is the limit for HP....
This isn't an LT1 but should give you an idea what's possible with some money and forced induction... 1,300HP street car!
http://www.invisibill.net/TT_C4/
Now if you were asking what the limit of the LT1 block is, I'm not sure but with you budget no need to be limited by a stock engine block.
Last edited by DMITTZ; Aug 8, 2018 at 06:19 PM.
Race Director
Joined: Sep 2001
Posts: 14,680
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From: NEwhere Ohio
Smokey yunick used to say 600 crank hp was limit for stock sbc cast crank, but that was probably for a 5000-6000 lb truck or station wagon which your corvette is not.
so i believe > 600 crank hp is possible with stock cast sbc crank on a ‘lighter’ corvette.
forged pistons i dont think are required bc look at new supercharged or turbo engines, most dont have forged pistons anymore ! They key is engine mgt and not to detonAte. But those cars still do have forged cranks now though...
so i believe > 600 crank hp is possible with stock cast sbc crank on a ‘lighter’ corvette.
forged pistons i dont think are required bc look at new supercharged or turbo engines, most dont have forged pistons anymore ! They key is engine mgt and not to detonAte. But those cars still do have forged cranks now though...
Last edited by dizwiz24; Aug 8, 2018 at 10:25 PM.
Le Mans Master
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From: Everett WA
C4 of Year Finalist (appearance mods) 2019
You might consider getting in touch with Tom Wong of Wong's Performance Engineering in Vancouver WA. Tom is one of the top corvette tuners on the west coast and started out in C4's
Safety Car
Joined: Apr 2003
Posts: 3,793
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From: VA
So... I’m in the process of building my 94 corvettes LT1, so far MY GOALS were 600rwhp! From what builders I’m contacting they are saying those are the limits of the LT1.
600 didn’t seem like that much to me, what are numbers being produced and what did it take to get there. Budget is around 20k for engine.
600 didn’t seem like that much to me, what are numbers being produced and what did it take to get there. Budget is around 20k for engine.
Last edited by VenkmanP; Aug 9, 2018 at 01:17 AM.
Racer
Joined: Jul 2017
Posts: 422
Likes: 53
From: PA
So... I’m in the process of building my 94 corvettes LT1, so far MY GOALS were 600rwhp! From what builders I’m contacting they are saying those are the limits of the LT1.
600 didn’t seem like that much to me, what are numbers being produced and what did it take to get there. Budget is around 20k for engine.
600 didn’t seem like that much to me, what are numbers being produced and what did it take to get there. Budget is around 20k for engine.
I seem to remember the author stating he would not try to go above 450hp or so with a stock crank, rods, & pistons. I also think he said the 2 bolt vs 4 bolt main did not make that much difference in the orig design of the LT1 block.
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Pro
Joined: Apr 1999
Posts: 533
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From: Poinciana Florida
600 rwhp
I have a mild mannered super charged 598 rwhp grocery getter which at this point in my life takes me to and from Disney World. An acquaintance of mine added a 100 shot of nitrous to a similar build and was pulling 722+ rwhp.
It can easily be done, but why? The heads appear to be the limitation with the Lt-1. You have the money to spend and have no investment at this point. Go with an Ls engine or build a large cube small block. Just my view if I had to do it again.
It can easily be done, but why? The heads appear to be the limitation with the Lt-1. You have the money to spend and have no investment at this point. Go with an Ls engine or build a large cube small block. Just my view if I had to do it again.
Melting Slicks
Joined: Jan 2017
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From: Minneapolis MN
Le Mans Master
Joined: Sep 2013
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From: near the thumb in the mitten
20k gets past most limitations. You will need 396 or more CI. IMO heads and intake are the tough part because of limited choices . A splade LT1 block should hold beyond the 600 you are looking for. The rest is sbc. Golden has built 700 hp NA LT1s, IDK about durability.
Race Director
Joined: May 2006
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From: 1000 Vin Scully Ave, L.A California
With that budget I'd go LS swap. Or maybe a newer (2014+) LT1 with a blower and forged everything. Why not buy a crate engine from GM that has high HP and go from there?
Last edited by CVG323; Aug 10, 2018 at 02:59 PM.
Melting Slicks
Joined: May 2013
Posts: 2,692
Likes: 349
From: Sacramento California
My thoughts exactly. Yes the original question was about the limits of the LT1 specifically. But $20k is a fat budget, so I start thinking LSX with forced induction or other tasty options. I think a new LT5 crate motor is about $18k...?
Race Director
Joined: May 2006
Posts: 11,865
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From: 1000 Vin Scully Ave, L.A California
https://www.gmperformancemotor.com/parts/19332702.html
LT4 640 HP $14,186
not bad
I'd go with this
LS376/525 6.2L LS3 Engine 525 HP
$8,498.74
LT4 640 HP $14,186
not bad
I'd go with this
LS376/525 6.2L LS3 Engine 525 HP
$8,498.74
Last edited by CVG323; Aug 10, 2018 at 07:42 PM.
Race Director
Joined: Oct 2012
Posts: 17,383
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From: Melbourne, FL
All the guys telling you to "just la swap" are nuts. That would take a LOT more time monand money, and youd end up with a half breed wacko that nobody will get near (tuner or buyers). If you want the easy route, buy a c5 and put a blower and a host of other mods on it. Or buy one already done for 15k.
Another thing, 600whp is a HUGE number. That's like 750 crank, and on an Na build would render any corvette all but undrivable. Just something to think about. I know a lot of YouTube videos and anonymous posters on forums make it seem easy and cheap, but those are for entertainment only, and most are complete lies.
Another thing, 600whp is a HUGE number. That's like 750 crank, and on an Na build would render any corvette all but undrivable. Just something to think about. I know a lot of YouTube videos and anonymous posters on forums make it seem easy and cheap, but those are for entertainment only, and most are complete lies.
Race Director
Joined: Oct 2011
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From: Dallas Texas
2025 C4 of the Year Finalist - Modified
The sound of built LT is miles ahead of any LS IMO. You'll make less power yes, but everyone has an LS. Build that LT up and make the C4 look wicked.