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Techical Discussions => Tech- - Engine => Topic started by: Jason Goldsack on March 24, 2011, 12:32:11 PM

Title: cam choice
Post by: Jason Goldsack on March 24, 2011, 12:32:11 PM
What would be a good aftermarket cam choice for the 361 in my Windsor.. currently I have a 383 magnum cam in the 361.. but I bet a modern cam would work much better.

The car is street driven.. will probably get 3.23 gears and stock converter..




Title: cam choice
Post by: Guests on March 24, 2011, 12:58:34 PM
Find something with a lift in the .475 range, duration of 260-270. Don't want anything too big because of the stock compression and stock converter, but this will wake her up and still give you daily drivability.  If you go with something in a 2000rpm stall, then you could take the lift up to .500 without a problem, flat tappet cams have their limitations compared to the roller cams.
Title: cam choice
Post by: Rich on March 29, 2011, 08:46:34 PM


 I had the same cam in a previous engine that I built from scratch, and it put out well over 400 horsepower. Ran that one with a factory HP converter that stalled at 2,400 rpm and 3.23's and it was awesome!

krautmaster2011-03-30 01:48:32
Title: cam choice
Post by: Jason Goldsack on March 30, 2011, 02:58:46 AM
I will check that out.. any idea how much vacuum you have.. I have power brakes..

Title: cam choice
Post by: Rich on March 30, 2011, 07:14:57 AM
Plenty to run the power brakes -14'' at 900 rpm idle. Initial timing set to 15* BTDC, another 20 mechanical all in by 2,500 rpm (35* total), add another 20* from the vacuum advance when cruising for 55* - runs good , no ping.
Title: cam choice
Post by: Corey on March 30, 2011, 08:08:05 AM


go with a mopar performance purple shaft cam they have different set ups  you can choose. I put one in the 400 i had in my fury though i just went basic and got a four barrel cam but it worked great for me. as far as specs it just depends on what you want.
Title: cam choice
Post by: Snotty on March 30, 2011, 08:54:36 AM
I don't remember which magazine it was (I could look it up) but in one of the recent Mopar rags the tech author said no to using a purple-shaft to a writer that was asking the same question.  He said the PS cams are living on reputation, but are way behind modern technology today.
 
Not saying this as an argument, but as an FYI. 
 
Title: cam choice
Post by: Corey on March 30, 2011, 01:23:09 PM



I did not know that thanks for the info scott :)
stinger11702011-03-30 18:23:48
Title: cam choice
Post by: Jason Goldsack on March 30, 2011, 02:06:27 PM
I agree with Snotty.. the PS is an old design that was done on paper.. that's why i want to upgrade..

Title: cam choice
Post by: Jason Goldsack on March 30, 2011, 04:06:40 PM


Quote from: krautmaster

 
I compared this cam to the Lunati  60300 cam on Desktop Dyno...

Comp XE268H - 189 HP at 5500 rpm 191 LB/FT at 4500 rpm - it wouldn't even let me run the simulation with the log manifolds this one was with the HP manifolds
With small tube headers it made  251 hp @ 6000 and 249 LB/FT and 5000 rpm..

Lunati 60300 -   286 HP at 5500 rpm 364 LB/FT at 3000 rpm with the log manifolds
.454 lift / 208 duration at 0.050
HP Manifolds made no difference in HP and 1 lb/ft in torque... that was it..
With small tube headers it made 318 @ 5000 rpm and 389 LB/FT @ 3500 rpm

It seems the comp cam is more of a revving cam and the Lunati would give me the grunt..




1965Windsor3612011-03-30 21:09:43
Title: cam choice
Post by: Rich on March 31, 2011, 05:01:43 AM
 I think your Desk Top Dyno program is not working properly. When I've put the Comp cam in other 383's they have all made at least 300 rear wheel horsepower/340 ft lbs. The Voodoo is a much milder cam (smaller duration and lift - the Comp XE268H has 230* at .050, .484" lift). 
 Mine goes on a DynoJet 248x chassis dyno this afternoon for carb tuning, so I'll let you know how it turns out. (I get three runs for $65!) 
Title: cam choice
Post by: Jason Goldsack on March 31, 2011, 06:16:17 AM
Are you running log manifolds like me? That's what I based the tests on.. not HP or Headers..

Title: cam choice
Post by: Guests on March 31, 2011, 08:24:32 PM
Check the Comp cam at .050 specs. If you put them in as 268 @.050, it's about what the results would show (it should be about a 224@.050 (http://mailto:224@.050)).


It may be better after proper calc over the Lutani (and cheaper), my first cam in my 361 was a Melling 308 duration advertised and .475 lift. I had no bottom end with 2.73s, which was probably a good thing as far as burning rubber and wasting tires goes, but she was fine off idle and fun to redline (5200rpm lifters/springs). I always had 12-15inches of vacuum which was more than enough.
Title: cam choice
Post by: Rich on April 07, 2011, 08:29:59 PM

 Dyno showed 309 RWHP at 4,800 rpm,  340 ft-lbs at 3,200 rpm. Dyno guy said it correlates to about 360 crank HP and 400 crank ft-lbs (25 more HP than a stock 383 Magnum). The power was limited on the top by the little 600 cfm carb I have on it for mpg purposes. Low end torque decreased some - it's now hard to burn rubber with the 2.76 gears, but the passing gear is loads of fun and highway cruise is effortless and smooth. 

krautmaster2011-04-08 01:32:52
Title: cam choice
Post by: Jason Goldsack on April 08, 2011, 02:53:28 AM
Great power!