Lunati Hemi cams advice

[RussY]

Yeah, I think if you are going to cam up a street Hemi you need to add some deeper rear gearing to let it rev. I’m somewhat surprised how much stronger my 440 GTX feels off the line than my stock Hemi, both 3.55/3.54 gears. The 440 is an auto that helps with torque multiplication but still surprising. But that Hemi rush after the revs starts building is something the 440 doesn’t have.

I have had and have 440 cars and I agree they feel a lot stronger. I would love to put the Tremec TKX with the deep first gear in it, but I won't cut the car up to do it. My gut feeling is the car is missing some power, it runs great, it is smooth, and fires right up. By gut feeling, I mean I have a Chrysler 300 with the TNT 440 and a 500hp C2 vette. I have checked the timing and tune, looks spot on! I have receipts for the engine build and it appears to have been done right with a lot of money spent, well aware that it doesn't mean a lot, unfortunately the cam is not specified. My intention is to pull the timing cover, valve covers, and carefully check everything. If I don't find anything like a retarded cam etc, I would like to be prepared to put a cam/lifters in it with known results. I have searched the internet extensively and finding camshaft tests/results for the stock size hemi are pretty elusive other than "great power from 3-6k," which seems like the manufacturers go to statement for every cam. I find that interesting for such a legendary motor. Side note, the car rarely gets driven and I can handle a little "drivability" issue or two. I really appreciate everyone's comments.

 

[69 hemibee]

Why not get a hemi specific cam, hemisonly, raybarton etc

 

[RussY]

Why not get a hemi specific cam, hemisonly, raybarton etc

Have made several inquiries about that, seems that there are no cam cores to grind for FT cams.

 

[gtxrt]

I would find out what cam you have in there now and go from there. where does your engine not make power low end or top end or both. do you have power brakes.

 

[H. Lindley]

I've used Isky cams in 2 Hemis. 284 Mega on intake and 292 Mega on exhaust. Idles with a little lope and made 500 horse with headers in a stock 426. Agree that Hemis don't have the bottom end of the 440s, but pull hard when the front carb opens. 6 barrel 440s are the best; pull hard everywhere.

 

[gtxrt]

before you check your camshaft I would do a compression test for the health of the engine plus it will help pick a different cam if you need one.

 

[RussY]

I've used Isky cams in 2 Hemis. 284 Mega on intake and 292 Mega on exhaust. Idles with a little lope and made 500 horse with headers in a stock 426. Agree that Hemis don't have the bottom end of the 440s, but pull hard when the front carb opens. 6 barrel 440s are the best; pull hard everywhere.

before you check your camshaft I would do a compression test for the health of the engine plus it will help pick a different cam if you need one.

GTXRT Thanks, I will. Mr. Lindley was that two different cams, or the same cam with a split duration in two different engines

 

[H. Lindley]

Same cam with split duration in 2 different engines.

 

[PsyOps]

Why not get a hemi specific cam, hemisonly, raybarton etc

The OP says in post #4 that Ray Barton only does rollers.

 

[Road Rat]

BULLET CAMS

8785 Old Craft Rd
Olive Branch, MS 38654
662-893-5670

Grind Number CRH 280/287-12FC Part Number 300000 SN T31156
CHRYSLER 426 HEMI
Intake Exhaust
Duration at .050 250 258
Lobe Lift .3600 .3600
Separation 112. OP CL OP CL
Timing Events @.050 16 54 64 14
Duration @.020 280 287
Gross Valve lift .565 .547
Rocker Ratio 1.57 1.52
Valve Lash .020 .020
Degree Intake Lobe to 109

Ray Barton used this cam on my 540 Hemi in a 2020 build. Used his rocker system so the final lift is slightly different. He uses the tool steel solid lifters. No complaint.

 

[69 hemibee]

The OP says in post #4 that Ray Barton only does rollers.

Must be a recent change, I've bought a few solid FT cams from him.

 

[PsyOps]

I just looked at RBRE website and it appears he only offers 3 solid rollers:
CHRYSLER GEN II HEMI CAMSHAFTS

 

[RussY]

I just looked at RBRE website and it appears he only offers 3 solid rollers:
CHRYSLER GEN II HEMI CAMSHAFTS

I called a couple of months ago and he said that the cam blanks or core were unavailable. Nice conversation although I would guess I am not his primary target customer, wish I had the $$$ to order one of his and set my stocker aside.

 

[PsyOps]

I called a couple of months ago and he said that the cam blanks or core were unavailable. Nice conversation although I would guess I am not his primary target customer, wish I had the $$$ to order one of his and set my stocker aside.

I hear you. Sadly, it seems the entire world is moving to roller cams in one form or another. Those of us that prefer flat tappet cams, for whatever reason, are going the way of the dinosaurs. It's not unlike the evolution of the single barrel carb, to the two barrel, to the four barrel, to throttle body efi, to the now commonplace multiport efi.

 

[autoxcuda]

BULLET CAMS

8785 Old Craft Rd
Olive Branch, MS 38654
662-893-5670

Grind Number CRH 280/287-12FC Part Number 300000 SN T31156
CHRYSLER 426 HEMI
Intake Exhaust
Duration at .050 250 258
Lobe Lift .3600 .3600
Separation 112. OP CL OP CL
Timing Events @.050 16 54 64 14
Duration @.020 280 287
Gross Valve lift .565 .547
Rocker Ratio 1.57 1.52
Valve Lash .020 .020
Degree Intake Lobe to 109

Ray Barton used this cam on my 540 Hemi in a 2020 build. Used his rocker system so the final lift is slightly different. He uses the tool steel solid lifters. No complaint.

I agree, call Bullet.

I like the 110 to 112 for a stock setup like the OP's.

But the way that is going to behave with your motor with 114 more cubic inches and lot more stroke is going to be different than than in a stock 426 cubic inch

 

[INTMD8]

If you don't want to rev it why not stick with a stock cam? I would think even stock 6000-6500 would work great.

I have a comp cams 24-601-5 227/249 107. Having had it in a "stock/crate" 426 I wouldn't recommend using it but may be a usable core for you?

 

[RussY]

If you don't want to rev it why not stick with a stock cam? I would think even stock 6000-6500 would work great.

I have a comp cams 24-601-5 227/249 107. Having had it in a "stock/crate" 426 I wouldn't recommend using it but may be a usable core for you?

That’s crossed my mind but I think there is a little room for improvement over the stocker. Long duration and relatively low lift. I will get back to the car in a couple of weeks. Been swamped with a kid coming home from the east coast, grad school. Good thing is the pay raise coming my way

 

[OldGuyGTX]

answered a post about the negatives of a split duration cam when the exhaust has a lot more duration than the intake duration.

negatives less vacuum less bottom end. hemi needs lots of gear for stop light to stop light they were almost like a small block and had to get the rpms up to make power. they were getting beat a lot on the street unless they had lots of gear and good tuning and a dist recurve.

I simply disagree, a lot, that the 426 hemi (solid lifter that pulled hard to 7K) acted like a small block off the line, if anything, just the opposite, 426hemis were known for their "gobs" of torque...this is from experiential knowledge of driving a '69 hemi rr, 833. The '69 GTX I have now has the same super track pack the hemi had, but the 833 has been changed out to a built 727.

The Lunati 703 might be a better fit for a 3.54 gear.

703

1800 - 6200 .501"/.537" 226/234 268/276 110/106 Hyd/Hyd
This high performance street cam likes
2400 RPM stall, 800 CFM carb, dual
plane intake and headers. Makes unequaled

power to 6200 RPM with proper
valve springs.

704

2200 - 6400 .520"/.558" 234/242 276/284 110/106 Hyd/Hyd
Hot street cam, likes 2800 converter, hirise
type dual plane intake with 850 CFM
carb, headers, 10:1 compression and 3.73
gearing. Likes up to 200 HP nitrous.