LT-1 Owners in forum

[70 LT-1 convert]

I have heard that the 70 LT-1 was under rated but I have not heard the 430 HP before. Where did that number come from? I have had several debates regarding the actual rating but, at least to this point, I could not support any specific number. CAn you point me to any support documentation.
Thanks,
Dean

 

[7T2 LT1]

I've Not Heard Of The 430 H.P. # Before Either

I second Dean's post,..I haven't seen an actual 430 H.P. number floated around in any of the old archive articles that I've uncovered to date,..can you point us to something specific? I sure wouldn't doubt the rating though because this is one pulling motor! Tom Save The Wave!!!

 

[Robert N]

Here is a link to the section that details some of what I have found regarding the HP rating:

http://www.blueridgewireless.com/vette/numbers.asp

Much of the theory comes from the upgrade from the 350/350 L46. The changes listed are significant enough to bump HP by more than 20.

Several race mechanics have estimated the set up to be much higher than the 370 rating. Remember though that peak HP is at 6000 RPMs, just shy of redline, so the usability of the HP is less than say a new ZZ4 crate motor and paek torque (380) is a 4000 RPMs. At the 4000 RPM mark, you can feel the pull in the seat of your pants. The high RPM mark for HP is a race set up for max power at high speed. This is roughly a streetable race car.

 

[0018]

Dean, 425-430 hp is the figure that Ive have heard from several knowledgeable sources. Consider this, the '65 327/365hp has a Holley 600cfm, instead of the 850 cfm as in the LT-1, 23 less cubic inches, plus the LT-1 has improved intake and exhaust manifold design for better flow. Not to mention stronger rods, steel crank, and 4 bolt crankcase in the LT-1. Cam, compression ratio and heads are similiar. Or compare it to the '70 350/350. I guarantee youll find alot more than 20 horsepower difference. I agree, I would like to see something in print or someone who can direct us to a website that could verify actual '70 LT-1 horsepower. I Would like to hear from others on what they believe regarding the '70 LT-1 and its actual horsepower. Remember, the LT-1 was built for big block performance, without the extra weight and handling problems of the Big Block, it had to pack alot ponies!

 

[F4Gary]

I wonder if the '71 & '72 LT-1's horsepower ratings were
also underrated for insurance purposes. I think that was one
of the reasons they all went to net horsepower in '72.

 

[Robert N]

Much of the reason for the drop in 1971 were modifications to the engine. I do believe that the HP at 330 for 1971 is still a under reported figure. The 1972 move to Net HP was not for insurance reasons (I believe), but to offer a more realistic number (20-25% loss in RWHP as compared to gross), and the drop in comparitive gross HP numbers were due in part to even more significant changes to the engine for pollution issues that had to be met.

 

[0018]

Gary, They were underated as well. Im guessing the the '71 at about 380 gross bhp and the 72 about 370, but its just a "ballpark" estimate. stu

 

[0018]

Re: Re: Appreciate The Info

I mentioned this earlier in this posting I believe. The LT-1/ZR-1 in the E-bay auction is the same one I mentioned parking next too at the Corvette show I attended. It is as nice as it is described in the auction!

Steve

Steve,
If I didnt have 2 teenage daughters to support Id sure consider a ZR-1. I hope Vettes like that go to folks who appreciate what it is, rather than some rich guy who just wants a high dollar Corvette. I have a '70 LT-1 ragtop with a hot rod '73 motor that deserves to be made right. If someone has a correct motor for this car, I will consider buying it or selling them the car. There just isnt that many '70 ragtops floating around and this one has the right colors (976/411) and is a clean Oklahoma car. Thanks for the info on the ZR-1. stu

 

[F4Gary]

Hey Steve, did your think your thread would go 4(or more) pages?!
I hope everyone on this thread has gone to the LT-1 registry web page and registered their car. I haven't paid the 40 bucks and joined yet but thinking about it. Also, Sal Carbone of Corvette Fever's "Shark Bites" has an Lt-1. Had his own LT-1 survey long before all of the other trendy "registries" and he told me mine was the earliest air conv. that he had a record of.
Can you beleive there is a "C5 Registry"! What an exclusive club!

 

[Robert N]

Sal's is alos a ZR1

 

[72LT1Steve]

Re: Re: Re: Appreciate The Info

Steve,
If I didnt have 2 teenage daughters to support Id sure consider a ZR-1. I hope Vettes like that go to folks who appreciate what it is, rather than some rich guy who just wants a high dollar Corvette. I have a '70 LT-1 ragtop with a hot rod '73 motor that deserves to be made right. If someone has a correct motor for this car, I will consider buying it or selling them the car. There just isnt that many '70 ragtops floating around and this one has the right colors (976/411) and is a clean Oklahoma car. Thanks for the info on the ZR-1. stu

Stu; I hear ya on the "support" responsability. My sibling commitment, along w/house, bills, etc. preclude me from a purchase such as the ZR-1 It would be very nice though if I could........Come on state lottery (23 million right now)

Steve

 

[72LT1Steve]

Hey Steve, did your think your thread would go 4(or more) pages?!
I hope everyone on this thread has gone to the LT-1 registry web page and registered their car. I haven't paid the 40 bucks and joined yet but thinking about it. Also, Sal Carbone of Corvette Fever's "Shark Bites" has an Lt-1. Had his own LT-1 survey long before all of the other trendy "registries" and he told me mine was the earliest air conv. that he had a record of.
Can you beleive there is a "C5 Registry"! What an exclusive club!

Gary; Never had a clue that this would go on for 4 pages. I hope it continues to 8, then 12, etc. I am very pleased to see everyone respond, and continue responding!
Congrats on your car being the 1st known air convert! What color combo to you have?

Steve

 

[0018]

Re: Re: Re: Re: Appreciate The Info

Stu; I hear ya on the "support" responsability. My sibling commitment, along w/house, bills, etc. preclude me from a purchase such as the ZR-1 It would be very nice though if I could........Come on state lottery (23 million right now)

Steve [/QUOTE

Steve,
I hope you hit for 23 million. I just purchased 3 powerball tickets. It doesnt hurt to dream. Good Luck!! stu

 

[xxaussiexx]

Hey Guys,
First time back onto the forum for some time.
Steve, glad to see that there are so many responding to your initial post, you may get to 8 or 10 pages yet. I will visit more often and try to assist. Sounds as if there are some nice LT1's out there with some very appreciative owners.
As an update on my "babe":..
With it currently being winter, I am not taking it out too often and have installed the hard top which tends to give the car a totally diffent personality.
Also I am currently rebuilding the rear calipers and uni joints on the drive and half shafts. So just fixing all those little things before the summer cruizin' season.
Good luck for the lottery, 23 million US dollars, thats nearly 45 mill in our "pacific pesos". Good luck

 

[F4Gary]

Steve, my car is supposed to be white, but when I bought it, it was painted Brans Hatch Green ( a '71 color) clearcoat. It is alot prettier than white. My car was built in febuary of '72 so I don't really know how close it is to being the first air convertible built. I've had the car for about 5 years. The dark green with the saddle interior really shows good. It also has a non-standard tan top. Later, Gary.

 

[72LT1Steve]

Hey Guys,
First time back onto the forum for some time.
Steve, glad to see that there are so many responding to your initial post, you may get to 8 or 10 pages yet. I will visit more often and try to assist. Sounds as if there are some nice LT1's out there with some very appreciative owners.
As an update on my "babe":..
With it currently being winter, I am not taking it out too often and have installed the hard top which tends to give the car a totally diffent personality.
Also I am currently rebuilding the rear calipers and uni joints on the drive and half shafts. So just fixing all those little things before the summer cruizin' season.
Good luck for the lottery, 23 million US dollars, thats nearly 45 mill in our "pacific pesos". Good luck

aussie; Good to hear from ya again! Missed the 23 Mil. now it's up to 28 Mil. Having a nice summer here in the great Pacific N/W. Having sunny skies with 85-90 degree days and low humidity. Can't ask for much more than that (well maybe more days off work to enjoy it).

Steve

 

[72LT1Steve]

Steve, my car is supposed to be white, but when I bought it, it was painted Brans Hatch Green ( a '71 color) clearcoat. It is alot prettier than white. My car was built in febuary of '72 so I don't really know how close it is to being the first air convertible built. I've had the car for about 5 years. The dark green with the saddle interior really shows good. It also has a non-standard tan top. Later, Gary.

Gary; The color combo does sound nice! Never have cared for white as a car color myself. Wouldn't it be cool [no pun intented ] if it was shown that is was the 1st air vert. Would definately look good on the resale resume to be able to list that 1st I would think.

Take care

Steve

 

[jmp]

Vancouver mountains

Hi Steve, I used to live in Vancouver, BC. Driving through the mountains in your car must be a great experience.

Well, I've now taken my LT-1 along the Sea-to-Sky Hwy to Squamish (and back) twice now... It's awesome!

One complaint though... everytime I hit 70+mph, my side view mirror tilts down and I can't see the poor S.O.B. I'm passing! (I wish all my problems were like this one! )

Anyone else notice the same thing? I guess my mirror is pretty loose, but it does seem like a poor design choice, from an aerodynamic point of view!


PS. The Sea-to-Sky Hwy goes from Vancouver, along the coast of Howe Sound, to Squamish, then up into the mountains to Whistler (about 2hrs, as the family-mobile drives). Very curvy, very fun.

 

[69autoXr]

Hi, I'm a new member and I wanted to tell you a bit about my LT-1. I don't have an original LT-1 car, it's a 69 coupe that I built the motor to 70 LT-1 specs, using a GM LT-1 cam, 2.02 heads, and 11.0:1 compression. I use the car strictly for autocrossing, and I love the motor. I'd like my next Corvette to a 70 or 71 LT-1 convertible, so that I have one to cruise on the street.

Chris

 

[gdh]

Just checked and it has been quite awhile since I last posted here, anyway I completed the 383 stroker buildup of my original engine and am putting out @ 490 hp. I went to the track for the first time ever and on my 3rd run I had a 12.46 # 116.2 mph. I haven't learned how to successfully launch yet, maybe I will go once or twice next year. I have 245 15's BFG T/A's so I had to be careful shifting into 2nd and 3rd as well. I keep all my original parts, and will be adding the C5 seats that I just picked up as well as stripping and re-painting late winter/early spring.