The 30-30 Camshaft vs. The LT 1

[Joe C.]

With optimal tuning, in 1970, the LT1 engine (350 Cubic Inches), produced 370 horsepower. In 1965, the L76 (327 cubic inches) engine with the 30-30 cam, produced 365 horsepower.

based on this, the LT1 produced 1.057 HP/C.I.

the L76 produced 1.116 HP/C.I.

[Duke W.]

Re: The 30-30 Camshaft vs. The LT 1

You have to take those old SAE gross ratings with a grain of salt. There was as much marketing hype as dyno testing behind them.

I've done a zillion simulations with both the 30-30, LT-1, Duntov, and L-79 cams on SBs of many different configurations. The 30-30 cam makes marginally more top end power than the LT-1 and doesn't roll off quite as fast beyond the power peak, but the LT-1 cam makes more AVERAGE power over the rev band whether you short shift or run the engine all the way to 6500.

If you were running at Bonneville, where the only thing that counts is top end power, the 30-30 would be my choice. For any other kind of duty from street driving to drag racing to road racing (in an otherwise basically stock engine that you don't want to rev over 6500), the LT-1 is the clear winner over all the others.

Duke

[Mike McKown]

Re: The 30-30 Camshaft vs. The LT 1

If'n you want a '64-'65 SHP engine to SOUND and RUN likes it's supposed to, by all means, use the 30-30 cam. The LT-1 cam doesn't idle like the 30-30 and to me doesn't sound near as good. If you can't sound good, what's the point of having a SHP engine anyway? You are subject to get blown off by a fart can Honda civic anyway. Putting an LT-1 cam in a 64-64 SHP engine is like putting 10-1 pistons in it instead of the 11-1.

If they don't bump like they're supposed to, I don't want it!

[Michael H.]

Re: The 30-30 Camshaft vs. The LT 1

Well said mike, I agree 100%. A big part of what I remember about Corvettes from the 60's was the way they sounded and I have never heard an LT1 cam make anything near that same sound. I still have 11.1 C/R and the correct cams in my cars and I have absolutely no intention of ever changing. I've installed quite a number of LT1 cams in cars over the years and none ever seemed to have the same seat of the pants power that the old original 346 cam had and they sure don't sound the same. I understand that Crane Cams sells an exact copy of most of the old original GM cam numbers, including the 143 big block cam. The beat goes on!

[Joe C.]

Re: The 30-30 Camshaft vs. The LT 1

Mike:

That is the response that I am looking for! Let's face it, we are not drag racing these old warriors. We also PROFESS to keep them as built(internally, as well as externally). With this in mind, and, MAYBE, considering the MARGINAL driveability (torque) advantage of the LT1 camshaft over the 30-30, then why should we sacrifice the hp/ci advantage of the 30-30 for the very slight driveability advantage of the LT1. Let us restore(?) our cars, and engines to their original configurations, regardless of any tech. advances. I agree with Mike.........the milder LT1 cam does not generate the same visceral excitement as the more radical 30-30, and should not be substituted. The 30-30 cam is considered by most, to be the most "high strung" smallblock camshaft design ever produced.

[Clem Z.]

the people i knew who bought corvettes

back in the 50s and 60s with the SHP engines all bought 4:10 rear gears and this makes a BIG difference on how they run with the 30-30 cam. after the purchase a lot changed to 4:56 or 4:88(my Z-28s ). i even bought my 396,427 and 454 cu in engined cars with 4:10 rear gears. if you can not spin the tires at 60MPH( my 482 cu in BBC powered pickup could do that ) what is the sense of driving a high performance car.

[Mike McKown]

Re: the people i knew who bought corvettes

You right man! Cam and gears! If you want to run a 3.08 and a close ratio ransmission, go with the LT_1 cam or even a stock hydraulic. If you wannna' go fast and sound good, use the 30-30 and gear it like you mean it! Myu experience with this cam and now is 4.56 rear with 2.20 first. 5.14 rear on a flirt!

[Frank H.]

Re: new-tech 30-30 , LT 1,97 cams

A couple years ago a good friends 64 365 cam had a exhaust lobe going flat,he found a used solid roller cam kit that he sent in and they reground to the
30-30 specs and added steel roller tip rockers,
I've had the car a couple weeks a few times and I still can't believe how much it improved the all around perfomance of the car,now on pump gas only,and no real changes made to it.

[John Liner]

Re: Hey -- I want one too

Will the 30-30 cam work with an automatic trans.? Isn't it a solid lifter cam?
My 79 L-82 has 3.70 gears and 10.5 new pistons in it, Comp Cams 350/350 Hydraulic cam W/1.6 Roller Tip Rockers and 69 side pipes. It runs fine and is civil on the street. What I want is a better sound and more power, I don't mind adjusting a solid lifter cam. Is this too rough a cam for a automatic Transmission?
Best regards,
John Liner 28230

[Wayne K.]

Wow, 482 cu.in. BBC........

the man likes big blockers and big knockers.

[Terry M.]

Re: The 30-30 Camshaft vs. The LT 1

Just as a matter of curiosity, what are you guys using for an exhaust system to keep the exhaust sound the same as original? My experience is that any replacement exhaust system alters the sound of the car dramatically.

[Gene M.]

Massaged Engines

Everybody builds a restored Corvette engine better that it was originally. It's the American way. I do. We always strive for a "stock" appearing and sounding small block or big block. But let's face it we use better parts and finer tolerances on everything internal. I use Manly stainless undercut and swirl polished valves, port match and bowl clean-up, 1.6 rockers, blue printed cheater cam or a selection from Crane or Comp cams that is a "little more" with Z-28 springs. The crank is balanced as are the piston/rods weight matched. Ring gaps are all hand fitted and all bearings are fit checked. Pistons are always forged TRW units. Timing chain is always a roller with the cam indexed for best low end. But I always use gaskets as original, stamped steel, cork, and paper because these are visible or detectable. All that being said I would suggest an aftermarket cam that has all the benefits of new technology and puts out more power over the entire RPM range and still sounds like a 30-30. I would not settle for the LT1 cam since it is lacking at the top end (wide lobe centers).

[John H.]

Re: Hey -- I want one too

John -

I wouldn't team up a 30-30 cam with an automatic transmssion - automatics want solid low-end torque, and the 30-30 doesn't have any. I've had several 30-30's in 327/365 Corvettes over the years and have one now in my stock/original '69 Z/28, and low-end torque is NOT a strong point of the 30-30; they sound great, have a nice lumpy idle, and work like gangbusters over 3500-4000 rpm, but are weak sisters at low rpm.

[Patrick H.]

Re: Hey -- I want one too

John,

To consider the next step, look at a hydraulic roller retrofit camshaft. Crane makes a few.

Patrick

[Joe C.]

Re: The 30-30 Camshaft vs. The LT 1

Terry:

I like my original 2 1/2" ramshorns into GM 2 1/2" sidepipes.