Lingenfelter 366 vs. 403
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 7,242
Likes: 8
Lingenfelter 366 vs. 403
Lingenfelter:
Are their hp ratings underrated? Although the torque is way higher, I just wonder why the 366 H/C package produces nearly the same numbers as the 403 package. (500/430 vs. 510/500).
Are their hp ratings underrated? Although the torque is way higher, I just wonder why the 366 H/C package produces nearly the same numbers as the 403 package. (500/430 vs. 510/500).
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
Horsepower underrated? You might want to ask Lingenfelter about that but IMO you're comparing apples to oranges....both ultimately 'taste great' (both packages producing significant increases in hp and tq) but they're just different.
The 366 slaps a supercharger on a stock cast-piston engine while the 403 drops-in a 'new' increased displacement, forged component motor. Both produce substantial performance increases, each in their own way.
For me, there was no question which way I wanted to go. I preferred (what I call) a "strong" basic engine, opting for the 403 package along with some other modifications. I loved my stock C6 but after the 403 conversion...there's simply no comparison. The car sounds and runs like I always thought a Corvette should....it sounds like the ultimate 'muscle car' and it's stupid-fast! (pics to follow)
Again, you might want to contact LPE and inquire about underrated horsepower but IMO both packages take different paths to the same increased performance destination.
My LPE 403 C6
The 366 slaps a supercharger on a stock cast-piston engine while the 403 drops-in a 'new' increased displacement, forged component motor. Both produce substantial performance increases, each in their own way.
For me, there was no question which way I wanted to go. I preferred (what I call) a "strong" basic engine, opting for the 403 package along with some other modifications. I loved my stock C6 but after the 403 conversion...there's simply no comparison. The car sounds and runs like I always thought a Corvette should....it sounds like the ultimate 'muscle car' and it's stupid-fast! (pics to follow)
Again, you might want to contact LPE and inquire about underrated horsepower but IMO both packages take different paths to the same increased performance destination.
My LPE 403 C6
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 7,242
Likes: 8
Interesting perspective. I just figured it made sense that a 403 would be a lot more powerful than a 366, if they have similar cams and such. I guess the torque is pretty dramatically different, though.
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
Originally Posted by cmb13
Interesting perspective. I just figured it made sense that a 403 would be a lot more powerful than a 366, if they have similar cams and such. I guess the torque is pretty dramatically different, though.
I'll post a dyno pull graph below showing my 403 vs. a stock Z06. My 403 surpasses the Z06 in both max power and max torque (although the Z can run 400 more rpm's). Also, it's not a gradual climb to peak #'s....the 403 produces what I call 'instant-on' power....the graph spikes up almost immediately. I also opted for a 'mid-range' cam instead of something even more radical. I love it, the car rocks at an idle but it is mild mannered (with muscle car sound) and driveable on the street. When you go WOT, it blasts! There's some problem hooking-up with massive tire spin but I just feather the throttle a bit.
I'm not done with the car yet....I've got a few more things I want to do.
Dyno pull compared to a stock Z06
Team Owner
Joined: May 2000
Posts: 25,344
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From: Frisco, TX
I think he's asking about the 366 package that is not supercharged, as it shows 500 BHP/440 torque on the LPE site.
My thought is you'd need to compare the dyno sheets of the two to see how the performance compares. Also, the 403 package has new and forged crank, pistons, and rods, whereas the 366 package does not, so it depends on your goals.
My thought is you'd need to compare the dyno sheets of the two to see how the performance compares. Also, the 403 package has new and forged crank, pistons, and rods, whereas the 366 package does not, so it depends on your goals.
Thread Starter
Le Mans Master
Joined: Nov 2004
Posts: 7,242
Likes: 8
Originally Posted by SteveL2
I think he's asking about the 366 package that is not supercharged, as it shows 500 BHP/440 torque on the LPE site.
My thought is you'd need to compare the dyno sheets of the two to see how the performance compares. Also, the 403 package has new and forged crank, pistons, and rods, whereas the 366 package does not, so it depends on your goals.
My thought is you'd need to compare the dyno sheets of the two to see how the performance compares. Also, the 403 package has new and forged crank, pistons, and rods, whereas the 366 package does not, so it depends on your goals.
How do you think it would depend on your goals? In what way would the two packages drive differently? I would think the 403 would provide more instant power at any RPM, although I'm not sure it would matter b/c the C6 has so much low end power anyway.
Racer
Joined: Jun 2003
Posts: 294
Likes: 1
From: Decatur Indiana
Originally Posted by cmb13
Lingenfelter:
Are their hp ratings underrated? Although the torque is way higher, I just wonder why the 366 H/C package produces nearly the same numbers as the 403 package. (500/430 vs. 510/500).
Are their hp ratings underrated? Although the torque is way higher, I just wonder why the 366 H/C package produces nearly the same numbers as the 403 package. (500/430 vs. 510/500).
The 366 package is essentially a heads and cam package. The 403 is a 4" stroke crank, rods, pistons to go with the heads and cam package. Hp seems similar, but what you are buying is a lot more torque. Yes we do rate a bit conservatively with our packages. HP is for talking, and torque is for walking.
Please also remember that all of these packages are rated with stock exhaust manifolds and catalysts.
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Team Owner
Joined: Mar 2006
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From: God Bless America
Originally Posted by Wayne O
Horsepower underrated? You might want to ask Lingenfelter about that but IMO you're comparing apples to oranges....both ultimately 'taste great' (both packages producing significant increases in hp and tq) but they're just different.
The 366 slaps a supercharger on a stock cast-piston engine while the 403 drops-in a 'new' increased displacement, forged component motor. Both produce substantial performance increases, each in their own way.
For me, there was no question which way I wanted to go. I preferred (what I call) a "strong" basic engine, opting for the 403 package along with some other modifications. I loved my stock C6 but after the 403 conversion...there's simply no comparison. The car sounds and runs like I always thought a Corvette should....it sounds like the ultimate 'muscle car' and it's stupid-fast! (pics to follow)
Again, you might want to contact LPE and inquire about underrated horsepower but IMO both packages take different paths to the same increased performance destination.
My LPE 403 C6
The 366 slaps a supercharger on a stock cast-piston engine while the 403 drops-in a 'new' increased displacement, forged component motor. Both produce substantial performance increases, each in their own way.
For me, there was no question which way I wanted to go. I preferred (what I call) a "strong" basic engine, opting for the 403 package along with some other modifications. I loved my stock C6 but after the 403 conversion...there's simply no comparison. The car sounds and runs like I always thought a Corvette should....it sounds like the ultimate 'muscle car' and it's stupid-fast! (pics to follow)
Again, you might want to contact LPE and inquire about underrated horsepower but IMO both packages take different paths to the same increased performance destination.
My LPE 403 C6
Safety Car
Joined: Jun 2002
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From: Northern VA
Cruise-In 7-8-9-10-11-12 Veteran
Wounded Warrior Escort '11
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
I also have the LPE 403 engine with LG Long Tubes and Corsa Sports. The car posted these numbers with just the headers and exhaust changes: 376 RWHP and 375 RWTQ. After the engine upgrade it now produces 470 RWHP and 468 RWTQ, both figures easily surpassing those of our Z06 brethren.
Plus, with this upgrade you still have the ability to take the top off (no, I am NOT referring to a delamination!) which the Z06 cannot do. Nothing is more fun than finding a Z06 driver and going wheel-to-wheel with him (especially if the top is off) and staying with him all the way. Certainly freaks them out.
Plus, with this upgrade you still have the ability to take the top off (no, I am NOT referring to a delamination!) which the Z06 cannot do. Nothing is more fun than finding a Z06 driver and going wheel-to-wheel with him (especially if the top is off) and staying with him all the way. Certainly freaks them out.
Safety Car
Joined: Jun 2004
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From: Whidbey Island WA
Just an observation but I think we all understand that the Z has more than motor upgrades and on a dollar ratio its pretty tough to beat with a base car. Not that I see anything wrong with adding motor to the base car. Most folks will never drive their base car to its maximum cornering potential making the Zs loftier limits superfluous. The extra ponies on the other hand will see some usage. As to which one and why..Any pathetic old people like me that have driven big and small blocks cars know that you can definitely feel that extra torque. Is it worth the money? A mans gotta answer that question on his own hook.
Safety Car
Joined: Jun 2004
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From: Whidbey Island WA
Still in AK. Came to Dutch to make a few repairs and get some lube oil and decided to hit the hotspot while the guy are getting things done. Wont be down south till after king crab which goes down Oct 15th. Thanks for the welcome though. 
Safety Car
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From: Miami FL
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
This thread is making me want one of those packages. For the money, the 366 (6 liter) seems the way to go for me. For those who like cubes, get the 403.
But in the end remember: The only things that beat cubic inches are rectangular dollars.
.
But in the end remember: The only things that beat cubic inches are rectangular dollars.
.
Safety Car
Joined: Jan 2006
Posts: 4,598
Likes: 78
From: Miami FL
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
Originally Posted by cmb13
So maybe we should stick with our lowly 400 hp????
No, NO, NO ! You need to SPEND the rectangular dollars on your car to beat the cubic inches. But you knew that
.