70 LT1 versus 70 LS5

[Erv M.]

I am starting my search for another car and wanted to know the pros and cons of these two models. Issues I am interested in are parts availability, overheating, reliability, quirks, etc.

Also curious to collectability since this year had such low production numbers.

I ordered and received the TIMJG for 1970 -72 to familarize myself with the particulars of each model. By the way; it is better than the TIMJG for 1968 -69, hats off to the team members.

[Steve B.]

Re: 70 LT1 versus 70 LS5

I am a big block guy but in this case I would pick the LT1. The 70 LT1 is a great motor with its 11 to 1 compression, solid lifters, plus lighter weight make it a winner over the LS5. The LS5 is a nice street motor with tons of torque but its not really the hipo engine that the LT1 is which hurts its collectability.

[Jack H.]

Re: 70 LT1 versus 70 LS5

First, remember the relative 'rareity' of 1970 vs. 1969 and say 1971 Corvettes is partially contrived. We don't know the full reason (there are various speculations), but the 1969 MY continued in production to 12/31/69 making it about 1.5 years in overall length.

The '70 models started production right after New Years making it a 'short' build of only seven months, about a half year in length. So, that's the primary reason for there being a 'shortage' of '70 Corvettes.

On overheating, reliability and quirks, I don't see anything decidely different about '70 compared to '69 or '71. When the parts are right, the car is right.

The LT1 is a NEAT high reving SB with only 1287 built compared to the 4473 units of LS5. The similarities and differences aren't that much different than in prior years where you had a choice between a SHP small block or a base big block. But, expect to pay a premium for the LT1 simply based on supply and demand...

On parts availability, well, each year of Corvette has some 'challenge' factors in this regard. But, I wouldn't classify the '70 cars as being as thorny as a '57 FI, a '63 or a '68 model. Those are well known for their myriad running changes and one year only components.

I'm sure others will have inputs for you too...

[Warren F.]

Re: 70 LT1 versus 70 LS5

I can tell you that the '70 model LS-5 is a torque monster, and if you enjoy being compressed into the back of the seat feeling, you will enjoy the LS-5 option. If you want more nimbleness thru handling, such as canyon driving, the LT-1 would be better suited.

I can tell you, that the big block will generate a lot of heat thru the passenger compartment. I would not recomend getting the option A/C with an LS-5, as the option only works marginally well and with this combination you do not get the fresh air vents down by the footwell. A non A/C optioned LS-5 is the way to go.

[Bruce F.]

Re: 70 LT1 versus 70 LS5

Agreed! I had a 71 monster with air and it was HOT! froze my legs with the air, but the rest of me.... In the summer by the time I got home I needed a swim!

My wife loves heat but that was over the top!

[Kenneth H.]

Re: 70 LT1 versus 70 LS5

Does anyone have any idea about the performance of a stock 1970 LS5 versus a stock 1970 LT1? I know that Car Life had an article in their August 1970 issue on the LT1 with test results of 5.7 sec. from 0-60 mph and a 14.18 1/4 mile time. I haven't seen anything on the LS5.

[Duke W.]

Re: 70 LT1 versus 70 LS5

The '70 LT-1 is a serious sports car. The LS-5 is more of a touring car. Think of your '69 300 HP with more torque or about the same low end grunt as the 300 HP, but it keeps making useable power to 6500-7000.

With some head massaging as on your '69, the LT-1 will be over 300 SAE corrected RWHP, and the the better weight distribution with a SB means better handling.

The LT-1 also won't be as thirsty as a big block.

Duke

[Kenneth B.]

Re: 70 LT1 versus 70 LS5

Does anyone have any idea about the performance of a stock 1970 LS5 versus a stock 1970 LT1? I know that Car Life had an article in their August 1970 issue on the LT1 with test results of 5.7 sec. from 0-60 mph and a 14.18 1/4 mile time. I haven't seen anything on the LS5.

The LT-1 is much faster 0-60 & the1/4 mile than the 454. The HP for the 454 was way overe rated & the LT-1 was probaly under rated. 454 was a ovel port 2 bolt main with a crappy intake & carb. The LT-1 was a 4 bolt with a high rise aluminum intake with a big Holly carb. I have 2 LT-1's & a loaded 454 performance wise the are not even close but the 454 is fun to drive.
KEN

[Chris H.]

Re: 70 LT1 versus 70 LS5

I have never owned a small block but I have owned two 396s and currently own a 70 LS5.

I would say it depends on how you like to drive your motors. Do you like to lug around or do you bang shifts off of redline?

I enjoyed redline with the 396s...not much low end torque but a big bang up top. The 454 on the other hand, is a different beast all together. Silky smooth idle, mountains of torque, zero maintenance requirements. I have come to appreciate all the unique characteristics of the 454. Oh, did I mention it's also wicked fast? It will run, if not smoke an LT1.

[Erv M.]

Re: 70 LT1 versus 70 LS5

I have been checking prices and they are all over the board. Live in Texas now and without A/C it would be parked all summer. One thing for sure whatever I buy will get driven.

[Dan P.]

Re: 70 LT1 versus 70 LS5

Let me start by saying I LOVE big blocks, but...

I own an '66 L36 427/390 (which I imagine compares to the LS5 in driving characteristics) and a '70 LT1. The cars were optioned from the factory at extreme opposite ends of the spectrum; '66 includes an M20+336:1 posi, AC, PS, PB, PW, TT, etc, etc. etc. The LT1 is a ZR1 with 456:1 posi and M22.

I concur with the the notion that they are completely different driving experiences. As accurately described above, the big block is a tourer, and the LT1 is a sports car. If gearing were the same, I'd say that straight line performance will go to the LT1 by a skosh - unless it's up against a solid lifter big block. That said, the LT1 will gain everything back - and more - in braking and cornering. Hence the spots car/tourer comparison.

[Kenneth H.]

Re: 70 LT1 versus 70 LS5

Irv, if you need AC then that rules out the '70 LT1. AC wasn't an option in LT1s until late in '72. You could get AC in the LS5 equipped 'vette in all years.

[Kenneth T.]

Re: 70 LT1 versus 70 LS5

Erv,

I guess I offer my 2 cents. I had a '65 327/365hp, solid lifters, side exhaust. I loved to drive it, winding it up and shifting, fairly nimble for a car of that day.

I bought my '71 LS5; different animal. Smooth idle, quiet engine, good acceleraton but slightly disappointed, small thing. I can pull away from a stop in second gear if I forget to downshift and once on the highway in fourth gear, if I want to pass someone I just tickle the throttle and it takes took off, no need to down shift. It tends to plow with the nose in a curve a bit, unlike the small block, but all in all it's a real nice driver.

Ken

[Wayne B.]

Re: 70 LT1 versus 70 LS5

That parts issue for the LT1 is a bear for me. The front grills are one year only, just try and find a date correct alternator (that's not six months salary) and of course the AIR pump won't be cheap either, I could go on for pages but it is nice having something there are so few of. A small run and semi-unique parts make restoring a "challenge" to say the least. But then again when you crank it up it is a beast. The ride will be different from a big block but then again it was made for road racing (beating up Porshe) so it has cornering on it's side compared to the big block, more balance of weight. The Lt1 was for racing and is devoid of creature comforts, at least creatures from this planet. AC? roll down the manual window and, in mine, FM? nahhhh that's just a passing fad. Power steering? nahhhh, that's for baby's so man up to parallel park.

[Kenneth H.]

Re: 70 LT1 versus 70 LS5

Wayne, the '70 LS5s have some of the same parts issues that we have with our LT1s. Granted they didn't (except for California cars) have A.I.R. systems, but if they had A/C they had the same (expensive) alternator, and the front grills were also the same based on date of manufacture. Same thing with the gas cap and a whole bunch of other parts.

And can you imagine if '70 A/C cars didn't use the 1100 884 alternator how rare they would be? I don't even want to think about it.