351c 2v cam question

[ScottM]

I am rebuilding a 2v engine (D2AE-CA). I believe that casting with the 2v heads makes it an H code. So I am going to ask the same question that has been asked a million times. I'm having trouble figuring out what cam to go with. Here is the scoop.

USE -- this is going in a 71 vert. It is gonna be a weekend cruiser with the wife. However, I want to scare the sh** out of the little punks who pull up next to me at a light in their Supra's and Miata's . I don't want to get crazy HP just good torque and a better than stock lope.

SPECS

1. FMX tranny
2. 2.80 rear gears
3. stock stall converter
4. standard bore with flat top pistons (which should increase CR a little)
5. Edelbrock 2750 performer intake
6. Edelbrock 1406 carb (600cfm)
7. Pertronix dizzy

HEADS -- stock springs, push rods, valves

Any suggestions are appreciated...I've been researching but there are just soooo many dang options I have confused myself...

 

[Don C]

You can play around with the spreadsheet in this post to give you an idea of what variables you need to take into consideration when selecting a camshaft.

Camshaft Selection

Attached is a spreadsheet that I have been playing with for a while, that is designed to give the user a starting point for selecting their camshaft. It also provides a starting point for torque convertor stall and carburetor size. It's also fun to just play around with, to see what happens...

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Going to a 3.50 rear end will likely give you more kick in the pants feel than a camshaft by itself.

 

[ScottM]

not sure what my compression will be since I am moving from dish pistons to flat top...I am not decking heads or block and plan on using regular fel-pro gasket...I know this has been done by many others and there have to be some numbers out there somewhere...

I believe my stock compression right now is 8.6...how much could those flat tops add is a good question...

 

[Don C]

The spreadsheet in this thread will let you calculate the static and dynamic compression ratios.

Engine and Compression Calculations

Attached is an Excel spreadsheet that performs several engine calculations. The first tab provides static compression ratios, while the second tab provides calculations for dynamic compression ratios. Note: Spreadsheets cleaned up and simplified on 10/10/2014 Note: Spreadsheets tweaked and...

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[mach71351c]

Change the rear gear if you want to take on a Miata! The cam may not be enough. 3.50s would be a better bang for the buck

 

[71ProjectJunk]

Here is the issue, with a stock stall speed converter and 2.80 gears you are extremely limited to what cam you can use. Cams change the torque curve of an engine, the bigger the cam higher up in the RPM range they make power, the issue is that they loose low end torque, everything is a compromise. As the previous poster said, the first thing would be to change the rear gears to 3.50's. That by itself will make a huge difference in acceleration, but it will affect your cruising RPM (higher highway RPM's) and your fuel mileage, again everything is a compromise. If you change your gears to 3.50's the biggest cam I would use on a 351 C with the stock torque converter would be somewhere around 215 degrees maybe 220 degrees of intake duration at .050 lift, and I would get a dual pattern cam (more duration and lift on the exhaust). In my experience, if you are unsure of what cam to buy always go with the smaller cam. Too small a cam will limit your top end power a bit, but too big a cam can give you all types of drivability issues, and make the car no fun to drive. Also remember that you will need to use the recommended valve springs for the cam you get, you cannot use the stock valve springs, that will usually entail getting the retainers and locks too. This comp cams with a stock converter and 3.50 gears would be as big as I would want to go:

Xtreme Energy 218/224 Hydraulic Flat Cam and Lifter Kit for Ford 351C, 351M-400M

Xtreme Energy 218/224 Hydraulic Flat Tappet Cam and Lifter Kit for Ford 351C, 351M-400M. Strong torque, excellent response and good mid-range. Stock converter. 3.23 Gears.

www.compcams.com

You can use those specs and get something close on your favorite cam manufacturer. I have assumed that with the flat top pistons you will be somewhere in the 9:1 to 10:1 compression ratio, which will be fine with the above recommended cam.

 

[DAverkamp]

not sure what my compression will be since I am moving from dish pistons to flat top...I am not decking heads or block and plan on using regular fel-pro gasket...I know this has been done by many others and there have to be some numbers out there somewhere...

I believe my stock compression right now is 8.6...how much could those flat tops add is a good question...

IMO, "scaring" a car that weighs 1/4 less than our girls do may be a challenge, but slapping on a 2750 Performer 2V with a 4bbl will help dialing in your low end torque when you decide which cam to use with the 3.50 trac-loc. I also trust you are bolting on a set of matched headers to compliment all the necessary parts to achieve your goal.

 

[c9zx]

If you want to keep all the stock components you listed, just use a stock replacement cam and abandon the idea of scaring Supra drivers. I strongly suggest you replace the multi-groove valves and rod bolt nuts. Both are know to cause catastrophic engine failures. Chuck

 

[ScottM]

Change the rear gear if you want to take on a Miata! The cam may not be enough. 3.50s would be a better bang for the buck

I plan on going to 3.25 locker in the future but I don't really want to be taching 3500rpm driving down the freeway...

So here are the 3 cams I'm looking at...to be honest im not sure what the factory cam specs are for a 1973 H code (has a CJ stamp D2AE-CA but is a 2v)

1. 268H - 218/218 @ 50 .494 lift 110 LS
2. XE256H - 212/218 @ 50. -- .487/.493 -- 110
3. XE262H - 218/224 @ 50 -- .413/.520 -- 110

thoughts...??

 

[ScottM]

If you want to keep all the stock components you listed, just use a stock replacement cam and abandon the idea of scaring Supra drivers. I strongly suggest you replace the multi-groove valves and rod bolt nuts. Both are know to cause catastrophic engine failures. Chuck

I replaced the rod bolts but I hadn't planned on replacing the valves...my machinist didn't seem to think it was necessary for a mostly stock engine

 

[ScottM]

IMO, "scaring" a car that weighs 1/4 less than our girls do may be a challenge, but slapping on a 2750 Performer 2V with a 4bbl will help dialing in your low end torque when you decide which cam to use with the 3.50 trac-loc. I also trust you are bolting on a set of matched headers to compliment all the necessary parts to achieve your goal.

yep shorty headers are coming too....just more time and $$$

 

[Mister 4x4]

I actually went with a CompCams K32-421-8 kit: https://www.compcams.com/magnum-215-215-hydraulic-roller-cam-k-kit-for-ford-351c-351m-400m.html, also a set of 17045-16 Roller Rocker Arms, Crane Cams 52655-16 screw-in rocker studs, Edelbrock 2750 Performer Intake, Edelbrock 1406 Performer 4bbl carb, Hooker Ceramic Coated Competition headers, Pypes 2.5" Street Pro stainless exhaust (w/X-pipe), Duraspark ignition upgrade w/Accel Super Coil, and some other things you aren't going to need (mine was seized when I got it, so I threw the checkbook at it). It's good for around 400hp at the crank, which is running through a completely stock AOD (including torque converter) from an '89 5.0 vert (which had 2.75s from the factory). It'll do burn-outs all day, sounds mean, and cruises the freeway at 70 while only turning 1800-ish rpms (thanks to the AOD).

Hope this helps.

http://www.mister4x4.net/cars/Mach_1/Frankenstang_20180928.mp4

 

[71ProjectJunk]

I plan on going to 3.25 locker in the future but I don't really want to be taching 3500rpm driving down the freeway...

So here are the 3 cams I'm looking at...to be honest im not sure what the factory cam specs are for a 1973 H code (has a CJ stamp D2AE-CA but is a 2v)

1. 268H - 218/218 @ 50 .494 lift 110 LS
2. XE256H - 212/218 @ 50. -- .487/.493 -- 110
3. XE262H - 218/224 @ 50 -- .413/.520 -- 110

thoughts...??

The 218/224 @ .050 was the biggest cam I would use, as I said above, but the 212/218 would also be a very good choice with better drivability, more low end torque, but a little less top end power. I would stay away from the 218/218 cam as it is a single pattern cam, but having said that, it would also work fine.

 

[Ron Tanzi]

I replaced the rod bolts but I hadn't planned on replacing the valves...my machinist didn't seem to think it was necessary for a mostly stock engine

As others have stated: replace your valves! It is as important as replacing the the rod bolts. Your engine is over 50 years old and if you have a valve failure it is party over. It is really cheap insurance.

Ron

 

[machphil]

2. XE256H - 212/218 @ 50. -- .487/.493 -- 110 is probably the best choice of the three you picked, though I'm not sure why you shied away from a 112 lobe separation. Maybe I'm just getting old but I don't have to emulate all of the other cars on the road today going, "frump, frump, frump". If you were to get that cam in a hyd roller you would be very pleased. Remember the vacuum accessories including brakes
when choosing the lobe separation.

 

[basstrix]

Here's the OEM cam data I have. The numbers are a little confusing...the top row is "advertised" and the bottom row is @.050 lift numbers.

 

[71ProjectJunk]

Here's the OEM cam data I have. The numbers are a little confusing...the top row is "advertised" and the bottom row is @.050 lift numbers.

View attachment 61907

Seems that the duration at .050 is off on that chart. I could be wrong, but they seem really low.

 

[ScottM]

from that chart, it seems like my cam 2v cam is nothing but a broomstick!

 

[Mister 4x4]

Yeah, those numbers do seem a little tame in comparison, eh?

Oh, I forgot to mention (in case it isn't obvious) that mine was a 2V from the factory (H-Code) and I kept the 2V heads to save a little money (which is why the Crane Cams rocker studs are so important if you're wanting roller rockers). I went 'roller everything' thinking it would reduce friction (and wear), which so far so good. My buddy who was a mechanic for 45 years was VERY pleased with how the engine came out, and even said it was one of the most free-revving street engines he'd seen in a long time (the "Holy Sh!t!" that came out of him when he bumped the throttle the first time was all I needed to hear).

My rear gears are factory 3.00, so they're actually a little bump from the 2.75s the AOD was accustomed to. A 19-tooth (beige) speedo gear keeps the speedometer happy.

 

[basstrix]

I either copied it from this post or we got the info from the same place.

71-73 351c original cam specs

I did some research on this*. Here's what I found for the various 4V engines: Engine; Duration degrees: int, exh; lift: int, exh; timing opening & closing degrees; overlap degrees 70-71 closed 4v. Part #D0AZ6250B. Casting mark: backward "B" followed by "R". 266, 270; .427, .427...

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