Performance Camshafts

Help Support 7173Mustangs.com:

DaveMT

Member
Joined
Aug 1, 2020
Messages
12
Reaction score
0
Location
Gibsonia, PA
My Car
1973 Mach-1 Sportsroof (1970, 351C-4V M-Code Motor, 4-Speed Toploader)
Does anyone have any experience using a "Comp" Cams XE284H camshaft in a 351C-4V (M-Code). I have been researching cams for awhile and am looking for a good performance cam for street and occasional strip use in my 1973 Mach-1 and so far I am leaning toward the XE284H. I don't mind a moderate lope at idle and actually like that sound in a street machine. I was wndering if anyone has any pros and cons on using this particular cam. My car has a 4-speed Toploader and 9" rearend with 3.25 gears and I will be adding headers soon but currently have a Edelbrock Performer manifold with a Holley 4160 (750 cfm) carb and an MSD 83501 Distributor.

 

c9zx

VIP Members
Joined
Sep 30, 2010
Messages
5,344
Reaction score
273
Location
Mustang, OK.
My Car
1972 Mach 1 Q code
2007 GT
1969 Cougar Eliminator B302
CSX 7000 Shelby Cobra FIA
2020 Edge ST
2002 F250 V10
+1 on what Canted393 said.

 

Hemikiller

VIP Members
Joined
Jul 12, 2010
Messages
3,322
Reaction score
514
Location
Killingworth, CT
My Car
71 Mach 1
65 coupe
+1 on what Canted393 said.
+2

https://summitracing.com/parts/cca-32-250-4/make/ford

I'm going to say the XE284H isn't a bad cam, but by how you are describing your engine, it's way too much cam for your application. Something in the 215*/225* @.050" duration range with a low .500" lift would work much better. Keep the LSA at 114* +/- 2* and it should still pull hard down low with a nice top end charge. If your vavletrain hasn't been overhauled with one piece stainless valves and single groove keepers, now is the time. 

 

Don C

Fords Forever
Joined
Jan 1, 2012
Messages
7,917
Reaction score
697
Location
Springfield, OR
My Car
1971 Mustang Sportroof M code
I agree with 393 and Hemi. Going with too big of a cam is a common problem.

You might try entering your information in the spreadsheet in this thread, this will give you a starting point for your intake duration. Keep in mind that Clevalnds like more duration on the exhaust.




 

DaveMT

Member
Joined
Aug 1, 2020
Messages
12
Reaction score
0
Location
Gibsonia, PA
My Car
1973 Mach-1 Sportsroof (1970, 351C-4V M-Code Motor, 4-Speed Toploader)
I agree with 393 and Hemi. Going with too big of a cam is a common problem.

You might try entering your information in the spreadsheet in this thread, this will give you a starting point for your intake duration. Keep in mind that Clevalnds like more duration on the exhaust.
Does it matter that my 351C-4V motor is an early 1970 M-Code (11.0 compression). Would it still be too much cam? Richard Holdener who seems to be quite an expert on small blocks (Chevys, Mopars, Fords, and his favorite is the Ford 351C) has a bunch of YouTube videos where he installed this cam in a pretty much stock 351C-4V M-Code with the same compression and closed chamber 4V (quenching) heads and produced 450 HP and 491 Lbs/Ft. of torque. Although those numbers were achieved well above the 5200 RPM mark.

 

DaveMT

Member
Joined
Aug 1, 2020
Messages
12
Reaction score
0
Location
Gibsonia, PA
My Car
1973 Mach-1 Sportsroof (1970, 351C-4V M-Code Motor, 4-Speed Toploader)
Using the spread sheet provided earlier, it tells me to use a cam with 290 degree duration and 110-112 degree LSA.

 

droptop73

VIP Members
Staff member
Moderator
Joined
Jul 5, 2010
Messages
6,393
Reaction score
183
Location
Grand Rapids, MI
My Car
73 Convertible
I'm running the Comp 268H cam and it has a nice slight chop and still pulls good vacuum.

Match the cam to what you intend to do with the car the majority of the time. If 90% street use you'll want to go with something that provides good drivability and pulls decent vacuum. If 90% strip use you'll need more than just a cam swap because it's never fast enough! LOL!

 
Last edited by a moderator:

Duncan Mach72

Well-known member
Joined
Jul 29, 2013
Messages
124
Reaction score
0
Location
United Kingdom
My Car
1972 Mach1
351C 4V, 4 speed
Alum flywheel
McLeod clutch
Torque biasing diff, 3.5:1
31 spline Strange SS axles
Dual 2.5" exhaust
Here's my recent experience. My car is very similar, only drivetrain difference is I have 3.50:1 gears. I used to run a Ford M6250A341 cam which has 510/536 lift & 214/224 duration at 50thou. I had a Performer & a 3310 (750VS) Holley. This was really tame! It delivered easy driving bottom end, you could make a sharp turn in top gear & drive off normally! Not really what I wanted from a musclecar with a stick, I want to work it & be rewarded. After driving round with a 429 with similar cam (lame top end, 14s/98 quarter mile) I recently put the 351 back in with a better cam & manifold. I reasoned if 0.5" lift was tame but 0.6" was race spec then I wanted 0.55" & figured I wanted to go up on duration to about 235/245. I struck lucky as a guy near me was selling a brand new Lunati solid lifter cam (41107LUN Grind SP02-305) 0.55/0.559 237°/247°LSA 108. Quoted Rpm range is 3200 – 6800. Basically with a 351C 4V it appears that if its cammed for 5500 rpm you will have 350 hp & if it can make 6500 rpm you will have 450hp. That's how the heads seem to work. I also got a Performer Air Gap at a good price, I am still tuning & because I am using a "too big" carb (850DP). I have just blocked off the plenum divider cutout, which is a crutch for a small carb. Prior to this the air/fuel ratio was all over the place but even so when I gassed it at 3000 rpm it pulled really hard, made me grin & I have not been above 5000 rpm ish so far as I'm supposed to be running it in. Looking forward to the next test drive/tune session this weekend. Get a good cam, ditch the Performer, don't look back!

 

ponypastor

Ponypastor
Joined
Jul 14, 2010
Messages
686
Reaction score
41
Location
St. Petersburg, Florida
My Car
1971 Ford Mustang Mach 1, 429 Super Cobra Jet, 4.11, Detroit Locker

For the rebuild of my 429 SCJ, I ordered a specially made camshaft by CAM Research in Englewood, Colorado.

The cam was specially cut just for my motor. That involves valve adjustment, gross valve lift, advertised duration, duration, valve timing. Perfect for my motor.

Give them a call and see if they might be able to help you get exactly what you need for your motor. 303-762-0022

 
Top