performer vs 268h vs x4262h amc variant

[rocketman123]

hey guys, trying to decide which cam to get:

i have at my house an edelbrock performer-plus amc cam but i was looking around at a couple other ones thay i thought might be better. no real power gain info on any of them for amcs so i was hoping you guys had some experience.

I am comparing the edelbrock one to either a comp cams high energy 268h or a custom grind similar to the x4 262 for chevys. i noticed in the cam notes for the comp cams that they take screw in studs and guideplates. i really wasnt wanting to do machining on the heads.

the cam will be going into an 86 grand wagoneer with holley truck avenger 670, edelbrock performer intake, doug thorley headers into bj's single 3 in exhaust fueled by a holley blue electric pump. transgo tf2 shift kit will also be going in with the cam. everything else is factory, no lift on it yet.

[rocketman123]

anybody???

[ironman_gq]

Best bet is to call the cam grinder and ask them what they think. I would recommend engle racing as I usually do. they are great to deal with and their cams dont require any extra machine work on the engine.

[pablorg]

I am also interested to know if the 268H is an improvement over the performer plus. Anybody?

[Dusty]

I am also interested to know if the 268H is an improvement over the performer plus. Anybody?

there is more to it than just sticking a cam in

what rpm range do you desire, where do you wan thte power to come on. you say a stock 360 so low compression is going to hurt bottom end with too big a cam. what is the torque converter stall?


talk to engle, lunati or reed they all seem to be pretty well versed in the AMC motors.

MC posted a 360 400 hp recipe you should check that out, lots of good tech. not you dont need screw in studs with the 268 but you will have to check and possibly cut your valve guides down, i doubt stock heads can clear i know my last two sets needed to be cut down to clear anything more than .480 lift. the one prior to that didnt need any cutting and cleared .507 lift.

There are several great 360 build threads with engines similarly setup to yours and with posted results here be it est hp numbers, seat of the pants or real world numbers to help you make a decission.

i wouldnt run the edelbrock performer cam there are better options out there for a motor larger than a 304 cubic inch.

[AMX69PHATTY]

Reed Cams is gone, finito, history, afaik

[Dusty]

yes they are my bad

[rocketman123]

Best bet is to call the cam grinder and ask them what they think. I would recommend engle racing as I usually do. they are great to deal with and their cams dont require any extra machine work on the engine.

yeah i sent a cam request to comp cams, still havnt heard from them yet but i will call them this week probably

[rocketman123]

I am also interested to know if the 268H is an improvement over the performer plus. Anybody?

there is more to it than just sticking a cam in

what rpm range do you desire, where do you wan thte power to come on. you say a stock 360 so low compression is going to hurt bottom end with too big a cam. what is the torque converter stall?


talk to engle, lunati or reed they all seem to be pretty well versed in the AMC motors.

MC posted a 360 400 hp recipe you should check that out, lots of good tech. not you dont need screw in studs with the 268 but you will have to check and possibly cut your valve guides down, i doubt stock heads can clear i know my last two sets needed to be cut down to clear anything more than .480 lift. the one prior to that didnt need any cutting and cleared .507 lift.

There are several great 360 build threads with engines similarly setup to yours and with posted results here be it est hp numbers, seat of the pants or real world numbers to help you make a decission.

i wouldnt run the edelbrock performer cam there are better options out there for a motor larger than a 304 cubic inch.

well im not too worried about driving around a rig without much low end, but with my weak compression there wont be much power at the top end either haha. i would like to have a little low end torque, but even now power doesnt come in until about 3000 so im used to it. i just want as much horsepower from a cam in the mid range as i can get while running factory components. i have the factory converter and gears too. cruises at 2800 at 70mph. i will check out the valve guide issue. im guessing i need to take off the heads and get them machined for that?? looks like the custom grind x262x4 is looking better.

[AMX69PHATTY]

An "RV" cam usually has an early Intake Valve Closing Angle to increase Dynamic Compression Ratio to make the most of a low Static Compression Ratio engine set-up. iirc Elgin offers a cam that is set up to work that way. Elgin also offers "HP" hydraulic lifters for AMC's that are designed to be ran with NO pre-load, or even .002 lash, which allows them to function as a solid lifter and improve top end performance.

[rocketman123]

An "RV" cam usually has an early Intake Valve Closing Angle to increase Dynamic Compression Ratio to make the most of a low Static Compression Ratio engine set-up. iirc Elgin offers a cam that is set up to work that way. Elgin also offers "HP" hydraulic lifters for AMC's that are designed to be ran with NO pre-load, or even .002 lash, which allows them to function as a solid lifter and improve top end performance.

Nice! Thats what I want. I will be installing the cam/lifters/springs by myself and it will be my first install so i dont really have a whole lot of knowledge. Im not sure what preload means? I can look up how to set up lash so im ok there.

Do you know what the part number of that cam is? or is it a family? they dont have any descriptions on their website about the cams, just the spec sheets and the duration families (A, B, C, etc).

I will call them monday and talk to them as well. Thanks!

[AMX69PHATTY]

Might be wrong about the Elgin Cam.
Low Static CR can be "compensated for" by any cam with an early Intake Closing angle.

Elgin info, this one has a low intake closing angle:

Elgin Part #E-912-P - Range B - 1500 To 4000
INT 0.281 0.449 280° 204° Open -3° BTC Close 27° ABC
EXH 0.296 0.473 289° 214° Open 42° BBC Close -8° ATC
Intake CL 105°
Exhaust CL 115°
Lobe Seperation 110°
Overlap @ Advertised Duration 65°

-> Range B - 1500 - 4000 RPM (Hydraulic: 195° - 210° Effective Duration)
Good to fair idle quality. Good low end torque and response in 1800 - 2600 RPM range. Good low end and mid-range power in 1500 - 4000 RPM operating range. Good fuel economy cam with correct equipment. Good choice for light towing. Compression 9.5 to 1 or less. Will work with stock or slightly modified engine, stock automatic or manual transmission. Recommended spring pressure 105 lbs for valve on seat; 265 lbs for valve open. Stock axle ratio 3.20 to 4.20 to 1 range. Not recommended for racing.

[rocketman123]

Here are the cam specs for the x4262h

RPM-Range: 1300-5600
Valve Timing: 0.006
Advertised Duration: Int: 262 Exh: 270
Lobe-Center Angle: 111
Duration @ .050" Lift: Int: 218 Exh: 226
Intake Centerline: 107
Valve Lift: Int: 0.462 Exh: 0.480
Lobe Lift: Int: 0.308 Exh: 0.320

Valve Timing @ 0.006" Lift: Intake Open: 22 BTDC, Intake Closed: 59ABDC, Exhaust Open: 68 BBDC, Exhaust Closed: 21 ATDC

"Hydraulic-Excellent response, good mid-range, noticeable idle."

Hows this look compared to that? I dont know much about cam spec sheets besides advertised duration and lift

[AMX69PHATTY]

Best bet would be to call the cam manufacturer and ask them imho.

[rocketman123]

yeah probably. thanks for showing me that cam though!

[rocketman123]

decided i might as well go with the cam thats similar to the x4262h. it is the xtreme energy xe262h for amc's PN 10-215-5. but it takes screw in studs and guideplates, so looks like this will be a summer project since i cant afford machinework right now...