Need help choosing cam?

[uhoh5.0]

I am building a carbureted 302 for my 66' mustang. I found a really good deal on a set of GT-40P heads that have been rebuilt, have aftermarket valve springs, some light porting work in the bowls, and a set of roller rockers
(1.7 I believe). I am using a "freshened up" stock 5.0 short block with original pistons and new rings, rod and main bearings, as well as ARP rod bolts. I need to make a decision on what cam will work best with these heads. In searching old threads, a lot of people like the TFS stage 1 cam and there is always a following for the Ford Letter cams, both B & E with these heads. I am also thinking a dual plane victor jr. intake and probably a 650cfm Holley street avenger. The car has a C4 and 3.55 gears in a Ford 8" rear. It's a pretty light car too (no exact numbers yet). It will primarily be a street/cruising car so I want to build a good low end to mid-range motor with lots of torque down low.
Any suggestions are greatly appreciated!
Thanks

 

[Cobra1741]

i say call anderson ford motorsports or call or email comp cams. either one of those will tell you what cam you need to optimize your build. xe270hr, n-21 afm cam. those are the cams ive been looking at, i have an e303 and its single pattern so dont even look at those cams as you need help on the exhaust side with gt40s

nevermind i saw you want grunt, i guess try and fin da cam lower than 220* and 112 or 114 lsa.

Xe264hr
Duration at .050 inch Lift - - 212 int./218 exh.
Valve Lift with Factory Rocker Arm Ratio - -0.512 int./0.512 exh. lift
Lobe Separation (degrees) 114

 

[uhoh5.0]

That's good info! I think I'll do what you suggested and call AFM and comp and see what they recommend and then I'll post that too and we can toss the different ideas around. What does single pattern mean? I'm thinking some of those cams that are designed for EFI/Mass Air wouldn't be optimal for a carbureted motor also? Correct?

 

[uhoh5.0]

This info is from Anderson's web-site:

N-412 Camshaft works with stock OEM pistons with 1.6 roller rockers. RPM range 2300-6200.

302 c.i.d. This cam is to be used with 1.6 R.R. Great with GT-40, TFS or Edelbrock heads. Minimum 24lb injectors and 75mm mass air. Recommend 3.55 to 4.10 gears. Great drivability down to 1800 rpm, nice idle, rpm range 2300-6200, works best with 89-93 EEC, needs 2500-2700 converter.

 

[uhoh5.0]

Specs on TFS Stage 1:

*This cam is the most reasonably priced of the lot too!

TFS Stage 1 Camshaft
Trick Flow Specialties Stage 1 Track Heat Hydraulic Roller Camshaft for 5.0L Ford

Good idle, strong midrange power
Basic Operating RPM Range - 2,000-5,500 RPM
Aftermarket intake, heads, and headers recommended
Duration @ .050" - 221°/225°
Valve Lift with 1.6 Rocker - .499/.510
Lobe Separation - 112°

 

[uhoh5.0]

I downloaded Comp's "Cam Simulator" and put in the flow numbers for the GT-40P heads and with the XE270HR it says a stock bottom end 302 with dual plane intake and 600cfm carb would make 335hp @5500rpm and 375 ft. lbs. tq. @ 4000rpm this is with long-tube headers. This is about where I thought the combo would be, roughly about 275 rwhp

 

[Cobra1741]

thats in an ideal engine build. there will be loss. ya u can run the n412, and maybe the n-21 if you have 1.7 roller rockers.

Single pattern has to do with the duration of the cams between the intake and the exhaust side. the letter cams are all single pattern meaning the durations are the same....e303...220in/220ex duration.... our heads need a longer duration on the exhaust side so try to find a cam thats set more around 218/224 which is the xe270hr, or the other cam im looking at (n-21 afm) 219-229* i believe, the 270hr is at 112lsa and the n-21 at 110lsa...110lsa installed dot to dot gives a pretty choppy idle due to overlap, but it sure sounds nice =) but sacrifices driveability.

 

[89stang1]

I downloaded Comp's "Cam Simulator" and put in the flow numbers for the GT-40P heads and with the XE270HR it says a stock bottom end 302 with dual plane intake and 600cfm carb would make 335hp @5500rpm and 375 ft. lbs. tq. @ 4000rpm this is with long-tube headers. This is about where I thought the combo would be, roughly about 275 rwhp

+1 Great choice!

 

[uhoh5.0]

That particular comp cams says it is to be used with 1.7 ratio roller rockers. The set of heads I am getting comes with a real nice set of crane 1.6 rr's already installed. I'm thinking that trickflow cam might be a really good choice. It has a little extra duration on the exhaust side and also slightly more lift. I think that would work well with the P heads smaller exhaust valve? I think I just answered my question about the dual pattern cam, lol!

 

[uhoh5.0]

More info on Trickflow cam:

Product Line: Trick Flow® Track Max® Hydraulic Roller Camshafts for Ford 5.0L
Part Type: Camshafts
Cam Style: Hydraulic roller tappet
Basic Operating RPM Range: 2,000-5,500
Intake Duration at 050 inch Lift: 221
Exhaust Duration at 050 inch Lift: 225
Duration at 050 inch Lift: 221 int./225 exh.
Advertised Intake Duration: 283
Advertised Exhaust Duration: 291
Advertised Duration: 283 int./291 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.499 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.510 in.
Valve Lift with Factory Rocker Arm Ratio: 0.499 int./0.510 exh. lift
Lobe Separation (degrees): 112
Intake Valve Lash: 0.000 in.
Exhaust Valve Lash: 0.000 in.
Computer-Controlled Compatible: Yes
Grind Number: HR-224/339-2S-12

 

[Cobra1741]

its a good strong cam for driveability and there are alot of people out there making good power with it.

 

[uhoh5.0]

I appreciate the explanation on the cam specs, I missed that previosuly when scrolling down. I will need a cam that will work with the stock 1.6 rr ratio, or the comp would be very nice. I kind of like the price on the Trick Flow cam too, it's like $100 bucks or maybe a little more cheaper than the comp and probably $120 less than the AFM

 

[Cobra1741]

i always say you get what you pay for =) but in the case of the tfs 1 you will def. be doing better than the e303.... the xe270hr and n-21, n-41 from afm, are badass cams man for what you want... dont get the xe270hr from comp cams, its like 300 from them, you can find it for 250 around, i know it sounds pricey compared to the tfs 1 but i think it might be a little more aggressive, all depends on what you want! you can get whatever you wanna know from the net. keep researching and research exactly how a cam works and you can basically find an off the shelf cam that you want without asking anyone... good luck with your build. be sure to post your dyno numbers or track times!!

 

[uhoh5.0]

Anderson Ford Motorsport recommended the AF-B31, they also estimated rwhp between 250 and 280 with the parts I mentioned. I am going to give comp cams a call also.

 

[uhoh5.0]

I did so more work on Competion Cams Cam program and I think that XE270hr would be a great cam. I picked up a book with some dyno tests in it, and there was a dyno with a stock bottom end 302 at .030 over yielding 306 cu in with the XE264 torque cam, GT-40P heads, Edelbrock air gap intake, and Speed Demon 650 cfm carb. That motor made right at 336hp @3700rpms. The XE270hr doesn't seem to sacrifice anything torque wise and it looks to be good for about 10+hp over the 264. I'm just going off the stock out of the box flow statistics for the GT-40P heads. The heads I have are ported, and have a nice set of roller rockers. Anyways, I think a realistic flywheel number for this combo with longtubes would be right at 350hp. I'm hoping that a real world estimate of rwhp would be right at about 280ish hp. I think that kind of power with 3.55 rear, C4, and about a 2500 converter would make for a great street car. Great driveability, good low end torque, plenty of HP, and able to build on a real budget. Thoughts?