Building an LT1 clone?
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Burning Brakes
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From: Upland Ca
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From: Forked River NJ
The heads are marginal compared to what is out there today. The cam is old school. Long duration short lift. More power can be made with modern cam design. I had an LT1 and got bored with it very quickly. Good in its day but better technology is here.
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From: Corsicana, Tx
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Sounds like a perfect candidate for a 383 or 396 stroker combo. No need to stay at 350" for hauling a '56 Chevy around.
JIM
JIM
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From: Taylor Michigan
The 1970 engine is the best of the lot with special pink rods that are extremely hard to find and expensive to purchase if you want the real thing...in other words not all LT1`s are the same. They dropped 40 HP from 70 to 71 with 72`s even lower.....Where it went I dont know besides lower compression....I believe they even offered AC on the last ones and a possible hydraulic cam as the tach redline was a lowly 5500 rpm.....
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From: Forked River NJ
The 1970 engine is the best of the lot with special pink rods that are extremely hard to find and expensive to purchase if you want the real thing...in other words not all LT1`s are the same. They dropped 40 HP from 70 to 71 with 72`s even lower.....Where it went I dont know besides lower compression....I believe they even offered AC on the last ones and a possible hydraulic cam as the tach redline was a lowly 5500 rpm.....
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From: Westminster Maryland
Hi,
I've thought the drop in H.P. from 71 motors to 72 motors was due to a change in rating criteria. I believe the 71 was measured at the flywheel with no accessories (gross), while the 72 was measured at the rear wheels (SAE).
Merry Christmas!
Regards,
Alan
I've thought the drop in H.P. from 71 motors to 72 motors was due to a change in rating criteria. I believe the 71 was measured at the flywheel with no accessories (gross), while the 72 was measured at the rear wheels (SAE).
Merry Christmas!
Regards,
Alan
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From: Reno Nevada
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Nothing to uh and ah about.
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From: Crossville TN
If you don't have a block with 4-bolt mains, you probably don't want to build anything too stout (no over 400 hp, anyway). If you want more from a small block, you need to special machining for greater strength, forged components, etc., etc. I agree with the others: if you want lots of power and durability, put in a new crate motor that is built for that kind of power...not a 40 year-old block that put out less than 200hp.
If you just want the engine to "look" like an LT-1, have at it.
If you just want the engine to "look" like an LT-1, have at it.
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From: Corsicana, Tx
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The January 2010 Hot Rod had a neat series of dyno tests where they flogged a 327/365 a 302/290, a high compression and a low compression LT-1 as well as a few Boss 302's 351CJ's etc. neat stuff!
JIM
JIM
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From: NYC NY
If you want a motor for a Tri 5 Chevy you need to think about torque. While those cars are not that heavy they are BIG. No substitute for cubic inches. I have a '55 Nomad with a ZZ3 and while it's "nice" to drive it needs more power. You should consider building yourself at least a 383 and make it a "torque monster". It will be way more "fun" to drive. In the end you will be much happier with the performance.
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From: Taylor Michigan
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I drove and or road in a bunch of these 70's and pre 70's vettes when they were new. Back then it was the big blocks that ruled. When I was child I thought like a child also referring to the (the new 70-72 LT1 owners.)
I would be ashamed to even drive a 13.00+ C-3 Corvette. I would not show up at the drags and brag about it. I've had solid and solid roller 350 ci motors and I thought that I had something when I could do low 12's and drive it 175 mph in open road races
Then the guy with a 496 or 540 leaves you in the dust. So unless it is over 600 hp it doesn't impress me at all. I've got to road race the brand new 505 hp C-6 Z06 and it did not impress me.
I would be ashamed to even drive a 13.00+ C-3 Corvette. I would not show up at the drags and brag about it. I've had solid and solid roller 350 ci motors and I thought that I had something when I could do low 12's and drive it 175 mph in open road races
Then the guy with a 496 or 540 leaves you in the dust. So unless it is over 600 hp it doesn't impress me at all. I've got to road race the brand new 505 hp C-6 Z06 and it did not impress me.
Race Director
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From: Taylor Michigan
The 70 Lt1 was not unbeatable, but it was the best of the small blocks before and after it....but a good one should be able to stand up to and face off to a warmed over Grand National..... but that also depends on who maintains the 70....Bench racing parts dont get the job done, its the competition and combination of the Vette and driver that finally determines the outcome...
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From: Millington Illinois
St. Jude Donor '08-'09
The problem with building a 1970 LT1 clone is it runs on race fuel now. It was a High RPM beast in the day but that day is gone. The only reason to build that engine today is if you have a 1970 vette or camaro that had one originally.
Build a 383 or 396 stroker with good heads and a roller cam.
Seriously you can get 100 HP more and much better torque though the entire RPM range and run on pump gas.
Build a 383 or 396 stroker with good heads and a roller cam.
Seriously you can get 100 HP more and much better torque though the entire RPM range and run on pump gas.
Race Director
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From: Millington Illinois
St. Jude Donor '08-'09
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From: Florida
The 1970 engine is the best of the lot with special pink rods that are extremely hard to find and expensive to purchase if you want the real thing...in other words not all LT1`s are the same. They dropped 40 HP from 70 to 71 with 72`s even lower.....Where it went I dont know besides lower compression....I believe they even offered AC on the last ones and a possible hydraulic cam as the tach redline was a lowly 5500 rpm.....
