Modern equivalent of my cam --

[pdq67]

that I want to run in my 325" SBC engine.

My solid lifter, flat-tappet cam is an Elgin PN 1133-P:

280/246, 108/106, .498" gross lift and needs .030" hot lash on both sides.
Going to install 1.6 ratio rockers to make it act like an around .500" lift cam so don't want to go over .500" lift lashed.


Engine will be right at 10.0 to 1 CR with a 4.155" b x 3.00" s;
Intake is a Holley 300-36 with a tuned 3310-2, 750 cfm vacuum secondary carb;
Cheap 1-5/8" 4-tube, long tube headers, open when I want to hear her cackle;
My new EQ 200 cc intake port, 50 cc chamber with 2.02"/1.60" valves;
Icon PN 746 pistons that have a stepped/flat-top, 2 valve notch design;
6.25" rods;
Quench, I will try to hit .040" by juggling head gasket thickness;

I just want something to compare the Elgin cam to is all so would you cam guys please step up?

I mean if I am leaving a bunch of hp on the table trying to run the way old-style cam, I will probably do like you guys have said and buy a modern one.

Thanks,

pdq67

[KOLI11]

I am new to this forum. Please dont take this the wrong way.

Over the years I have seen you posting threads all over different forums. What I gather is that
you are extremely knowledgable person, especially in camshaft. Would you be able
to make a very educated guess on choosing what new modern cam to get?

KOLI11

[barnym17]

PDQ I am definately no expert but in my opinion yes a more modern profile even with the same duration and lift specs will make some more power because they were designed with modern valve springs in mind.They can be ground more aggressive between the opening and closing points,sort of like comparing a roller vs hyd flat tappet of the same duration,the valve opens and closes quicker giving more average time to fill the cylinder.However on the plus side of your old cam its gentle opening and closing rates are much easier on the valve train,usually allowing gentler springs to be used which equals less pressure on the contact surface between the cam and lifter adding longevity.Its all a trade off you have to decide if a few extra ponies is worth the extra risk of a wiped lobe, more frequent spring changes,more attention to maintenance of the valvetrain etc.

[F-BIRD'88]

Take the cam you got and instead of running the lash at .030" set it at .014" to .016"
and go for a ride. it will be a whole new different camshaft.
Test it.... Drag test it...Road test it..Chassis dyno test it.... Play with the lash.
Play with the installed phasing...

This will give you a clue in what the car likes.

Then give CamKing a call, and let him pick the next new different cam for you.

Remember if you want a BIG HORSEPOWER cam, by nature with a 325 CID engine you need to rev it up
and put some gears in it to get the car to use the power to set you lil butt in the seat
when you hammer on it.

(that 3310-2 carb is really going to hold you back unless it is "modernized" a lot.)
But you can use the metering block and the bowls as a donor for a custom built 750 VS carb.

[Kbails]

I am not a cam guy. but I throw one out there
maby something like grind # 12-651-5

Valve Lash:.016/.018
Valve Timing:.02
Duration:278/284
Lobe Separation:108
Duration @ .050" Lift:248/250
Intake Centerline108
Valve Lift:531/525
Lobe Lift:.354/350
exaust;closes atdc:17
exaust; opens bbdc:53
intake opens btdc:16
intake closes abdc:52

[OILEAKY]

Is this engine intended for drag racing only, or dirt, or street , and will gas mileage matter ? How often will it see 6000 + rpm ?
Makes a difference.

[pdq67]

Is this engine intended for drag racing only, or dirt, or street , and will gas mileage matter ? How often will it see 6000 + rpm ?
Makes a difference.

1st off to answer KOLIII, it is just that I am not all that up on the new cams is all. I will say that I have a heck of a stash of old cam spec's that I have gathered up through the years.

Now OILEAKY, my engine will see 8,000 rpm on occasion. Just a street engine here. I am building it to be onna those, "When are you gonna shift the SOB!!", engines.. Just like I used to do my old junk301 years and years ago.

pdq67

[KOLI11]

I would say, have some fun and pick out the best old grind cam specs.

[Old School]

I would say, have some fun and pick out the best old grind cam specs.

I agree. With the valve springs you have you need the old lazy lobes. Why not use the Chevy 140 cam, lift will be below .500, lobes are very slow that will help in valve train stability and cam wear. If you want to do 8k you might not get there with only 246 duration. I have run the 140 cam 35 years ago and they were not bad but we had them in 4 speed cars and 4.10 gears. We shifted at 7400 with the best GM springs from the Chevy parts dept. They were a lot stouter from 4500 up than the 30-30 cam.

What kind of car is this going in? Trans? Rear gears? Weight?

[cgarb]

It will make it to 8k, you just need to find a longer downhill section of road.

[lefty o]

to be honest i run an old ultradyne that would be in the ballpark of what you want. 250x262 @106 .525". . granted its 20yrs old, so not super modern , but guarranteed its a world better than the old elgin crap. seriously though, id talk to one of the cam guys right here on the board, and get some input from someone who actually knows wtf he is doing.

[induction apprentice]

When I hear 325 inch motor i think 5.3 LS which ofcourse is not a flat tappet. Is this a first gen sbc?

[KOLI11]

to be honest i run an old ultradyne that would be in the ballpark of what you want. 250x262 @106 .525". . granted its 20yrs old, so not super modern , but guarranteed its a world better than the old elgin crap. seriously though, id talk to one of the cam guys right here on the board, and get some input from someone who actually knows wtf he is doing.

Spot on. Ultradyne is a legendary camshaft. It is always best to get advice from the experts, who know what they are doing and be there. I always wonder how often do these specialist cam grinders
make a new profile.

[pdq67]

When I hear 325 inch motor i think 5.3 LS which ofcourse is not a flat tappet. Is this a first gen sbc?

It is a 4.155" b x 3.00" s = 325" SBC based off one of my 400 blocks. I am installing new 50 cc chamber, 200 cc intake port heads, new 6.25" long rods, and a new LJ 3" crank. Got spacer bearings to install the 3" crank in my 400 block here.

Its going in my '67 350SS/RS Camaro that has an M-20, 12-bolt 3.31 posi- along with 26" to 26.5" tall WIDE tires along the lines of my way old L-60's..

I picked an about 280 cam because of my about 10 to 1 CR using stepped, 2 notch flat-top pistons and juggling head gasket thicknesses. It should hit 8,000 rpm but probably will run out of steam around 6,500 or so rpm.

I do know that an old Isky Z-30 cam will hit 8,000 but it is sure a knarly bugger! It's 290/250, 108/108, .480"/.480"lift, (and needs .030" hot lash on both sides per Isky).

My new cheap Elgin springs spec out about like Chevy's old -142 springs that were used with the old -140 cam so I should be fine, imho.

Its just going to be a street engine like, "When are you gonna shift the SOB?" sort a deal like my old junk301 was way back in the early '70's.

I'd gently roll her from a stop, get her up to like 3,000 rpm, and nail her up to 7,000 to 7,500 rpm and repeat when I shifted! What hoot.

I got a problem so will have to put this on hold because I just found out that I have to have a new left leg hip installed so probably be in limbo for over 6 months. BUT I am hopefully getting my left leg PAIN fixed? I had to do something because I am slowly losing it due to the f** PAIN!!

pdq67

[KOLI11]

pdq67,

Thats no good. Health comes first. I hope everything goes well and that you will have a super quick recovery time.

KOLI11