401 camshafts

**Duane Harr** · 07-14-2011, 09:28 AM

looking for advise on buying camshaft for 401 mild street rod engine i am building.

Thanks

Duane

**DocModisett** · 07-14-2011, 01:54 PM

Duane,
First off,,, the nailheads are not rpm engines... they are torq engines,,, any cam that has a broad torq band will work well in them....
The mistake that most guys make , especially the inexperienced ones , is to over cam the engine.... they put a cam in that does not start really pulling untill 3000 rpm or more when the engine is only good for 6000 absolute max.... most play out at 5500 to 5800.... so , dont over cam it....
another mistake that is made a lot is to put 2x4 carbs on for the ''wow'' factor without installing a good cam to handle them.....
With cams , a lot of times, less is actually more.... as for me ,,, I love the Buick 091 cam that came with the factory set up super wild cat engines along in 64-65-66 years.... it can handle big carbs, runs like a bear and does not rattle your windows out... if I could , I would buy a truck load of them....
if you contact some of the old cam grinders, Isky, crane, crower, schneider, engle, ect. some of them could grind one for you with specs close to the 091....
It was a Duntov grind, designed by Zora Arkus Duntov who worked for GM in the 50's and 60's and designed the performance cams for pontiac/chevrolet/buick/olds....
Once in a great while a man can run across a 091 cam on ebay.... and there is always TA Performance ect.... I am using a Poston NH400 cam that seems just right ... but they are out of business and I dont know who ground the cams for them.....

**wkillgs** · 07-17-2011, 08:40 AM

Tough question to answer. I don't believe there have been many dyno tests done on different cam designs, so it's difficult to say what works and what doesn't. Tom T has done some testing, but those were targeted towards race use....

The 091 Doc mentioned was the cam used by the stock class racers in the mid 60's.
About 0.440" lift, 209 degrees duration @ 0.050" lift with 109 degree lobe spacing. Buick eventually went to a 114 degree lobe spacing for a smoother idle. But the racers like the 109 degree better.

The old Poston NH400 is similar to the TA Performance TA 25. Both have 218/228 duration and but the Poston has 114 degree lobe spacing, while the TA has 110 degree.

Comp cams can grind a cam for you. Their standard designs range from a 'High Energy' 260H with 212/212 duration and 110 deg ls..... close to the stock 091 Buick cam.
Step up to a Xtreme Energy XE262H with 218/224 duration or XE268H with 224/230 duration for more top-end. A couple of guys have even mixed lobes.... such as a 218 duration intake with a 230 duration exhaust. That seems to be the hot tip...... but as I mentioned in the beginning, we still need dyno or performance comparisons to declare a winner.

As a baseline, I'd recommend a TA 25. But Comp cams seems to have more options to tailor a cam to your needs. Call them and ask for recommendations and post back with what they say.

**morepwr** · 07-17-2011, 06:58 PM

I bought a cam from isky asking talking to them and telling them that I was basically rebuilding my 401 back in stock form but wanted a little more torque. They ground me up a cam and I am very happy with it. You dont hear it at idle and it pulls plenty of vacuum for the brakes and it has much more low end grunt than it had before. Give them a call and tell them what you are looking for and they should be able tohelp you get what you want.