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LJM97Z 11-14-2012 03:55 AM

406 cam choices?
Want to hear any feedback on what FT Hyd. or Solid cams some of you are running in a 406 sbc, I'm at 3200 lbs. with me, its a 78 cutlass, I tried a larger Chet Herbert FT Hyd. cam but it had way too much overlap & was rated for 11.5.1 compression, car didn't respond well & it was a bear to tune, I'm either looking at the comp XE line, possibly a Lunati, I'd go Hyd. roller but just can't afford it right now. Hers is the engine combo.

10.4 compression, 205 cranking pressure
Iron Eagle 200cc heads
RPM intake, 750dp
1.5/8 headers
HEI ignition

I have choices of these 2 converters.

10" 2800 stall or 10" 4200

9" with 3.70 gears, 28" tire, but also have 26" ET Streets.

lg1969 11-14-2012 07:28 AM

I'm using a Comp Cam 280HFT with 1.6 rockers on my 406 with 11:1 compression. It has strong throttle response and a mild lope to it. Just google (Avatar) it and you will hear how the sound.

vinniekq2 11-14-2012 08:44 AM

I would use a solid flat tappet cam. 300/500 advertised is a good starting point.tune the icl for your application. should have a moderate idle and make power to 6,000

LJM97Z 11-14-2012 07:11 PM


Originally Posted by F-BIRD'88 (Post 1611055)
What are the specs on the cam you got.
I will show you how to use it and set the motor up for it.
it will run sweet once set up correctly.

The bigger cam is this one.

510/510, 245/245 @50 108 LSA 3000-7200

The one in it now is this one.

465/488, 224/234 @50 112 LSA 2000-6000

vinniekq2 11-14-2012 07:27 PM

that litrle 468 lift cam will be very tame in a 400.I doubt it would pull hard past 5300,,,maybe 6 in a 350.If thats the range you are looking to have the power?

LJM97Z 11-14-2012 07:34 PM

Kindof wanting something that'll pull good to around 5600 5800 or so, maybe i need a cam in the 230s on Dur. @50, I have run comp cams XE284Hs before with good results in both SB & BB, but they were Mopars.

I don't know what the deal is on the one 510 cam, It must have alot of overlap, It called for 11.5 compression, so that might explain why it didn't run right.

I just recently installed a 9" with 3.70 gears, i've really noticed a difference over the 4.11s, now my 4200 stall seems a bit much.

vinniekq2 11-14-2012 07:53 PM

I use a cam a lot bigger than what you are talking,with 3.50 gears., add 5 degrees for each 300 rpm or so. use a solid cam if you want power.

LJM97Z 11-14-2012 10:05 PM


Originally Posted by F-BIRD'88 (Post 1611367)
510/510, 245/245 @50 108 LSA 3000-7200

When using this cam it is very critical on how it is installed. .. intake closing point @.050"

The 510" lift cam will work a lot lot er if you install it like this.
Degree it in and advance it so that the intake C/L is on a 103 C/L
when measured at .050" the intake valve would close at 45.5 ABDC

It will have a ton of torque and plenty of cylinder pressure. with 10:1cr does not need 11.5:1.

further when you set up the distriutor this cam needs a ton of timing at idle
so much you can just simly lock out the mechanical advance and run full 36deg timing
It will idle nice and respond right off idle with the 4200 stall.
It will GLH.

You cam was likelu not advanced on install correctly or at all and the distributor curve was all wrong
a stock distributor curve will not work.

Install and set it up like this and it will do what you wanted it to do.

timing at .050" when you degree it should be open 19.5 BTDC and close 45.5 ABDC intake
exhaust open 55.5 BBDC ex close 9.5 ATDC
in C/L 103 ex c/L 113 it will be "5 degrees advanced" when installed like this.

makes a big difference.

Your 224-234 112 cam will run best when installed 5deg advanced 107 in 117 ex C/L's

.050" timing would be 5 - 39 in 54 -0 ex
with this cam recurve the distributor to have 24deg base initial at idle and 36deg at full advance
thats a 12deg mechanical advance curve.

This cam likes a 3000 stall. a 3500 stall is not too much, a 1700 is not enough.

Vacuum advance can and should be used too with both these cams ..limit to 12-15 deg max at highest vacuum use ported vacuum.

Either cam wil GLH when installed and set up right. The .510" will make the most power.
especially once installed correctly and the distributor corrected. (locked out is right for this one)
Use a 4.5' rated holley power valve with this cam.
the only reason this cam did not work well for you was the setup and installed position
Cam phasing.

So your saying even the small cam should advance 5*? I have the int. timing on this cam at 22* & 36* total, The larger cam i had the dist. locked out, plus i advanced it 4*, It ran better but still not great, The low speed/idle was the worst, It only pulled 5-6 inches vacuum which i though was low, I'm sure still needed more advance, plus i think the timing needed to come in earlier also, I ran a 3.5 PV, When i 1st. got it running to break in the cam it was a mess, I played hell getting it started, It acted like the timing was really slow but it was up there, so that was telling me it must have been way off.

I need to go back to the drawing board on the larger cam, In a couple of outings it pulled to 6800, thats a bit much IMO running stock rods/bolts,

vinniekq2 11-14-2012 11:01 PM

maybe you should list the other components in your engine? carb size,intake style,headers primary tube size,exhaust system,ignition? maybe there are a lot of problems. Ive never had big issues with camshafts,put them in and go fast. I prefer solid lifters for many reasons,,, never had a cam that was too big

LJM97Z 11-14-2012 11:08 PM


Originally Posted by vinniekq2 (Post 1611397)
maybe you should list the other components in your engine? carb size,intake style,headers primary tube size,exhaust system,ignition?

Didn't you see my 1st. post??

I normally don't have issues with camshafts either, just line up the dots & go fast, Now with this little cam i did run some 7.9s in the 1/8 shifting at 51-5200, my best MPH was 108, so its not to shabby, but it ran slower with the larger cam when i'm sure it should have ran better.

vinniekq2 11-14-2012 11:25 PM

hei stock is great to 5,000 RPM,after that it needs help. 1 5/8 primaries are great for low to moderate power,750 DP is a good carb. should be a tire melter. what shape are the valve springs in?

LJM97Z 11-14-2012 11:37 PM


Originally Posted by vinniekq2 (Post 1611405)
hei stock is great to 5,000 RPM,after that it needs help. 1 5/8 primaries are great for low to moderate power,750 DP is a good carb. should be a tire melter. what shape are the valve springs in?

The HEI is the Procomp, I know not the best, but it has not missed a lick, even at 6800 rpm, 1.5/8 headers i know are a bit small for the 406, The springs are like new, there doubles with pressures at 132 seat, 320 at .500 lift., It IS a tire fryer no doubt, just doesn't put down the ETs i think it should, my main concern was the cam (510) not perf. well, Its like I'm wondering if its a flow in the positioning of the key when it was built, I just lined up the dots on the little cam & it runs pretty good, pulls 16 inches vacuum (in gear). The 510 only got about 6 inches when i'm sure it should have been around 9-10.

vinniekq2 11-14-2012 11:52 PM

curious,what mph and ets are you getting?Im thinking high 11s?or low 12s

LJM97Z 11-15-2012 04:51 AM


Originally Posted by vinniekq2 (Post 1611417)
curious,what mph and ets are you getting?Im thinking high 11s?or low 12s

My best ET was a 12.43
Best MPH was 108
Best 60ft. was 1.73

Not all in that order. This was all with the small cam

I did run a 12.47 on a 1.87 or 1.89 60ft. though.

vinniekq2 11-15-2012 06:19 AM

The car looks like it is performing as it should.If that is your E.T, with mufflers,its actually decent.

what I would check,or look to improve:
Do you get enough fuel at the end of a 1/4 mile race?

I believe a victor junior and 850 D.P. would add another 3-4 M.P.H.

If the manifold/carb/fuel delivery added 5 m.p.h. then,,,I would use the hooker 1 3/4 primary pipe headers.
if that helped,then I would change cams after looking what helped the most

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