Duntov 30-30 cam

[Impalaguru]

Has anyone ever used one of these? Surely someone has!! Was thinking of putting one of these in the 327 in my convertible. Not sure exactly how they act. Really don't want something that's too radical. Just like a little lope with the lifter clatterbang
Any pointers would be great!
Ross

 

[Fathead Racing]

Yes, I ran one in a + .030" 283 CI engine in 1967. May be a little mild for a 327. Had a nice lope with + .030" 283 CI. Memory may have a little Fred Totten syndrome attached! :?

 

[348ShoeBox]

I ran a 30-30 in my 69 302 smallblock in 1972. It had 12:1 CR and was 30 over, nice lopey idle. I seem to remember ajusting the lifters quite often.

 

[roger gunter]

I ran one back in 1979-1983
283 bored to 301
202 heads
balanced and blueprinted
delarto 485 carbs
and also ran with 600cfm Holly
it ran good on the street has a little lump sounds nice and handles nice
good for a sbc just to have fun with

roger

 

[rstreet]

I have experience with these in the 60's and agree with Roger. Great sound! But not up to par with the later generation computer generated profiles. At one time I knew how they got the 30-30 name but have forgotten. Shoebox is correct about the adjustments but that was with stamped rockers and stock adjustment nuts. Back then you didn't mind pulling the covers off and "running through them" Heck did that after every other run!
robert

 

[Ronnie Russell]

.030/.030 valve lash

 

[348ShoeBox]

Robert,
You are right about the frequent lash ajustments,I did have factory rockers and nuts. My friend who put the engine together with me worked at the local chevy dealership and recomended the cam. The best I can remember why it was called a 30-30 was due to having the same lash setting on both intake and exhaust,not exactly sure about that.
Dwight.

 

[oldskydog]

You guys are mixing cams here, if not metaphors. The "Duntov" cam was the 3736097 (cast 3736098) solid lifter cam used in the 57-63 Corvettes and the cars with the solid lifter Corvette engine. The 30-30 cam 3849346 (cast 3849347) came out in 64 and was the chevy sb solid lifter Corvette and 302 Z-28 cam until the LT-1 cam 3972178 (cast 3972182)came out in 70. The LT-1 is considered a better cam for all earlier applications. .458int, .484 ex, 317 dur int., 346dur ex.

 

[Fathead Racing]

You guys are mixing cams here, if not metaphors. The "Duntov" cam was the 3736097 (cast 3736098) solid lifter cam used in the 57-63 Corvettes and the cars with the solid lifter Corvette engine. The 30-30 cam 3849346 (cast 3849347) came out in 64 and was the chevy sb solid lifter Corvette and 302 Z-28 cam until the LT-1 cam 3972178 (cast 3972182)came out in 70. The LT-1 is considered a better cam for all earlier applications. .458int, .484 ex, 317 dur int., 346dur ex.

Sounds like your probably right Cecil but Cam was presented to me as the Duntov 30-30. Back in them days I wouldn't have known the difference. Whatever the cam was it sounded good and the engine ran like stink in my 2dr post 55. I remember running a 383 Mopar with that car engine and whooped him 3 out of 3. Ran a 56 Chevy Belair in Erie Pa. with that car engine combo, whooped up on him pretty good too. After the race I headed back to the starting line behind a little rise in the road, next thing I know I'm in a tree lawn with the back seat against the back of my head. The guy came over that rise at about 80 mph and rear ended the 55. Broke the front seat from the floor and pushed the trunk and rear bumper where the back seat used to be. The horn got stuck on somehow so there I was in someones front yard at 2:00 AM with the horn blaring like hell. My car was still drivable but every time I let the clutch out the seat would tip back and it was like side stepping the clutch, I'm pretty sure the front wheels were off the ground more than once. The other guy in the Belair had his head stuck between the side of the seat and his driver side door. He was alright but what a riot! We made it to a garage in downtown Erie with my car but his car would not move due to front end damage. When the cops got there all he could say was, I sure can't figure out how that other car drove away? The guy that hit me told the cop a car hit him head on and drove away, what a night. Sorry about high jacking this thread but hearing about a Duntov cam brought memories of the 55 and that night in Erie.

 

[Tom Kochtanek]

Love those stories!

Ray, I beg to differ, it's great to recall the past. Every time you tell that story, I bet you get a little faster .

That said, do you guys think the cam in my original 327 (340 horse solid lifter build) is the so called "30-30"???

Thanks!
TomK

 

[oldskydog]

Ray, I beg to differ, it's great to recall the past. Every time you tell that story, I bet you get a little faster .

That said, do you guys think the cam in my original 327 (340 horse solid lifter build) is the so called "30-30"???

Thanks!
TomK

Tom,
Your 340 hp engine should have the 097 cam not the 30-30. The 30-30 came out with the 365/375 hp engine in 64.

 

[Tom Kochtanek]

Whew!

Sometimes I forgets... That 30-30 spec had me worried for a minute. It's been a while since I set the 327 valves, but I don't recall setting them at .030. I've got it written down somewhere, but now I recall that it is the so called "Duntov" cam.

Thanks!
TomK

 

[rstreet]

What was the Duntov Green Stripe cam that we used "back in the day". Was it the same as the 30-30 or
Robert
Ray loved the story and I have a couple similar 60's stories from "my other life" also but involve FE stuff so I probably would be banned.

 

[Impalaguru]

Thanks for the replies and for sharing the personal experiences!!

I guess I had my terminology mixed up on these cams. I've been doing some reading on the Corvette forums about these solid cams and, like Cecil said, there seems to be only three factory solid lifter cams that every one is talking about:

The Duntov, 30-30 and the LT-1.

I've thought about the LT-1 cam since it was used with automatic transmissions. I have a 4-speed but thought it might not be as radical due to that fact. Not sure if any of these three would even be considered radical.

Any suggestions from these three? I have: +.030 327, 9-9.5:1 comp. 461 heads (eventually), 2.5" ram horn manifolds, 4-speed and a 3.36 gear in a 63 Impala convertible. Plan on doing the cam with the heads.

Thanks again

Ross

 

[rstreet]

Ross I'm sure that Jim or Cecil will chime in with the best profile specs but my guess would be the LT-1. But..... I really am not convinced you will see enough difference to justify paying a premium for either one. So the one in the best condition for the best price is where I'd be?
robert

 

[boxerdog]

I remember when the 30-30 came out, we started calling the old Duntov the 12-18 (for the lash I think) and the new one the 30-30, and we also called them both Duntovs whether it was right or not.

I am sure the LT-1 is also OK and I am equally sure that you can easily get something from Comp, Isky, Bullet and a host of others that would be even better than the old GM stuff. The last 327 I did got a good pair of iron Vortecs set up for a Comp XS274S, 236/242 501/510. It really ran well and had an old-school sound that I liked, for not a lot of $$.

JMO

 

[oldskydog]

Ross,
If you want to replicate a 63 340 hp engine, the cam you need is the original 097 "Duntov". Here are some comments from a respected mech engineer and car guy fromanother forum.


"I/E .050" lifter rise duration is approximately 228/231 degs. The POML's are 108.5/112.5, which allows you to compute the LSA. This is a test! You do the arithmetic.

Gross lobe lift is .26250/.26650". Some specs multiply actual lobe lift by 1.5.

Beyond the above I can tell you that the Duntov lobes are symmetrical, and other the having .004" taller clearance ramps the lobes above the tops of the clearance ramps are the same at any point. In other words, if you measure the lobe at any angle between the POML and the tops of the clearance ramps the exhaust lobe is .004" higher than the inlet lobe.

Since the Duntov is a mechanical lifter cam, part of the .050" lifter rise is clearance ramp - .008/012", so if you want to compare the Duntov to a hydraulic lifter cam you have to measure durations at .058/.062", and the resulting 220/220 duration means that a 220/220 duration hydraulic lifter cam with similar lift would be pretty close to the Duntov.

If you want a true to original Chevrolet blueprint copy, the Federal Mogul Speed Pro CS113R is a no-brainer, and you can order it at any NAPA store.

Maybe some other grinder has a "Duntov" a little cheaper, but even if it shares the same high level specs as listed above you have no way of knowing for sure if it's true to print unless you have it analyzed by a Cam Doctor machine and verify the lobe indexing on the engine.

If you are looking for an exact replica of OE camshafts, Federal Mogul is riskless. You may find someone who claims they offer the same thing a little cheaper, but it's more expensive to find out for sure than just paying for the correct part at NAPA or Northern Auto Parts.

Duke"
If you want the LT-1 cam, the GM part number is 3972178. Cross reference that with NAPA or FM for their number. From all I've read and heard on the subject, I would not choose the 30-30 cam unless it was for resto purposes.
JMHO

 

[59 NSS - 409 Charlie]

Cecil is right. I bought a long blk from a GM dealer for drag racing in 64. 327-365hp and the cam was that 30-30 or part 346.

 

[Don Jacks]

I'm with Cecil here [maybe].I simply would look for a MODERN designed cam of simular duration at .050,you'll like it a lot better,believe me.

 

[k9hotrodder409]

I put the 3927178 LT-1 cam in Giny's 66 chevelle 327 when we raced together back in the day. The old girl was pretty god with a 4-speed. Her car ran strong all day . I don't remember the specs 24/28 maybe ?