Comp cams xe268h for 318

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If you guy's are having a difficult time with this just research Hydraulic roller issues on this forum.
I dont dispute that there are millions of OEM hydraulic systems on the road that are great, the after market performance stuff is a different story. If you dont believe me ask Yellow Rose what he thinks of hydraulics.
If been burned in the past, it wont happen again.
What all has to be changed to run a solid lifter on a stock engine? I'm assuming pushrods and I'm sure you would have to run adjustable rockers?
 
Just curious what type of abuse and rpm do you see failures? From daily driving? Idle to 4500? Street cars? Yea i can see it with 8000+rpm and race engines Baja trucks pulling trucks etc but a lazy 318 cruiser I dont see hydra lifters being an issue.
The last set of hydraulic rollers I tried were Comp retrofit's in a 340 street application around 450 hp they did not last 100 miles before they stopped pumping up. Had a flat tappet hydraulic colapse last year in a 360 mag that did not have 1000 miles on it.
Again, I dont doubt that many people run them successfully.
Just run a Google search on hydraulic lifter failures.
 
What all has to be changed to run a solid lifter on a stock engine? I'm assuming pushrods and I'm sure you would have to run adjustable rockers?
You are correct, push rods and adjustable rocker arms. Most can be run in the stock bore and oiling.
A lot of people run hydraulics so they dont have to set valves.
 
So is most of your complaints with hyd roller lifters? What could have changed thru the years that make them fail now more than 30 years ago? Do you think maybe its operator error? Improper installation? Or do you think its just poor manufacturing?
 
So is most of your complaints with hyd roller lifters? What could have changed thru the years that make them fail now more than 30 years ago? Do you think maybe its operator error? Improper installation? Or do you think its just poor manufacturing?
I believe it's all of the above, throw in crappy modern day oil and you have a real mess.
In particular, hydraulic and roller should never be used in the same phrase, kinda like jumbo shrimp.
I was told a a renowned engine builder that the aftermarket hydraulic components cant handle the pressure made by the steep ramps on a roller cam.
 
What is the proper way to install flat hydraulic lifters? Iv heard ppl say to soak them in oil iv heard ppl say not to what's the "correct" way?
 
What is the proper way to install flat hydraulic lifters? Iv heard ppl say to soak them in oil iv heard ppl say not to what's the "correct" way?
For a newbe,and the factory rocker system, put them in empty but oiled, and make sure they spin freely, in the lifter bores.
Then when you preoil, you park the cam in the correct two spots and fill the rocker shafts until all the rockers are oiling. By the time that is done, all the lifters will have the right amount of oil in them.
After that you can park the crank at TDC #1 compression, and install the oilpump drive shaft. Then Back the crank up to the 20* advance mark and drop the Distributor in. Then prefit the rotor and cap and index the #1 tower, install the wires,and she's almost ready to fire.
 
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And that truck 318 is not a roller block, right?
That is correct! Truck engines didnt get rollers until later car 318s got them in 85 I'm not 100%when trucks got them but iv rebuild 2 truck 318s (85s) and neither had rollers. This one is a 86 it dont either.
 
That is correct! Truck engines didnt get rollers until later car 318s got them in 85 I'm not 100%when trucks got them but iv rebuild 2 truck 318s (85s) and neither had rollers. This one is a 86 it dont either.
Iv been told that the trucks where lower compression and had different pistons I dont know if that is fact or myth doenst make alot of sense to me why Chrysler would dumb down an already low performance engine for a truck seems to me the truck would need better performance. But that being said I know the new rams are lower the hp and torque ratings between the truck and cars with the same size engines. Maybe it's just on paper to make the cars (challengers and chargers) seem more high performance. Idk seems dumb to me tho.
 
Howdy,
I built my 318 and run the xe268 cam
However
- alloy heads (65cc)
- block was milled to zero deck
- use kb167 pistons
- ld4b manifold
- hei ignition
- Holley sniper
- Factory 3.23 gears
- stock 904 t/c opened up and modified to about a 2100rpm stall
- comp ratio is about 9.6:1
- use 273 valve train with Toyota Corolla 4K pushrods
Next step will be headers, have some block huggers to go on, not much else will fit due to the steering box (rhd car) and possibly programmable ignition timing to work with the sniper

Car drives really nice, seems most comfortable at about 830 idle rpm, has a nice lope to it
That cam after the tune is in, should be able to idle down to 650 in gear,and 700/750 max,in neutral, if you wanted it to. Mine went 550/500easy, dragged down by the clutch, and idling around the parking lot. That was a Hughes HE2430AL,(223/230/110), in straight up. (367 cuber). That's when you find out how much power gets sucked up in the turns lol.

Nice combo.
 
I want to do that efi I'm between the sniper and the pro flo. Someday maybe when I hit the lottery and do my 318 turbo build. Lol
 
Unfortunately, not the case. Take 64 cc chambers and work it out. With the standard Felpro 8553PT head gaskets, your just tickling 8:1 SCR with pistons .075" in the hole at TDC. We all wish it was better.
first the 302 heads sposed be 58cc's i know there off some but thats what thay sposed to be! if head never been off its not a felpro gaskit its the ome steel .021ish shim gaskit! then the factory deck + or - however much its off from specs, but ant tryin to split hairs here as it probably is closer to 8 than 9,..even tho 9 what it sposed to be on these years of 318s...DWB
 
Absolutely yes,but I would not install that cam until I knew were the advertised was measured from, and if I didn't like the answer, I'd still throw it away. 278/288/112 with lifts of .421/.444,and .050s of 204/214 I wanna say;what a waste of a core/blank. Well 10 minutes on U-tube proves it; it idles like a 278/288 measured at .006
That will make the ICA around 68 to 70 degrees , which will kill any weakazz cylinder pressure you mighta had as a stocker.The Dcr works out to 6.1 with an 8.0Scr starting point. The 2800 is like putting a band-aid on a gushing wound.OK well maybe that's an exaggeration,lol. But I wouldn't even put that cam in my 367@ 11.3 Scr.


AJ the 278 is measured at .004 That is a long ground in Detroit cam with Crane's name on it. Remember Crane bought a big Detroit grinder
421 lift with 204 duration is a dead give away 204 @ .050 should have at least .450 lift and should be able to do it with [email protected] or 254ish @.006
as I said earlier there is no reason to have +12 on the exhaust today all that does is increase reversion
Mike Jones, Lunati, Howard, Bullet all have cams with around [email protected] with 450 lift so might Engle
The 248 DC cam would be a better choice with his compression, gears, converter, family (also mid 250 duration at .006) 248 is more like .008)
 
So in comparing apples to apples, how might the durations of that 278/288/114 cam compare to other's offerings which are usually measured at .006 or occasionally at .008?

I came to the same conclusions, as to the 204 needing more lift,and the 12* spread.
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If that 278 is say [email protected], or [email protected] Then it's just a low-lift cam with a cushiony landing. And if the closing ramp is a wee little longer than the opening ramp, it could still be decent low-lift cam with hot-dog idle.
I still wouldn't run it in a teener, or anything for that matter, even with 1.6 arms. There are just too many better offerings out there ........ IMO.
If I owned it, I might try to resell it....... but who to? I mean the first question out of a potential buyers mouth is gonna be; "why are you selling it?" And then AJ will have to come clean. That's why I said I would throw it away.
But you know; some streeter with too much compression, might be able to live with it. I mean, if it was a [email protected], with optimized Scr, and say .449/.474 lift with 1.6 arms , it is still gonna be fearsome in two gears to 65mph, with a starter of say 10:1, and a 2800TC ................. and the soft landing cam should be easy on the parts, for many years.
There is a bit of a silver lining to that cam; with a 12* split, you got about double the options of choosing an install,
but man is it gonna suck gas!
And look how much money you had to spend, just to be able to properly use that cam...
and the 114 LSA is still crazy.
But hey, dartfreak is gonna be a pioneer. Let's see how it goes.
 
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I have a question for the ones of you who say the summit (crane) or whatever it is grind is trash. And let me start by saying that I have great respect for you and acknowledge your experience and knowledge. But have you ever actually ran or drove a engine with the cam or you just saying its trash based on the numbers? Because I have read at least 10 or more reviews with ppl completely happy with it summits website has 3. One of them is a 4x4 360 he even commented on how great the low end torque was. So I'm curious have you had a bad experience with it or you just saying its trash based on the numbers on the paper? I get it the ramp like 74 is not ideal for cylinder pressure the 112 lobe separation doesn't help bottom end either but surely it cant be that bad cause summit still makes and sells these things after all these years. There is one video of a guy running it sounds pretty stout to me you can see the car squat at about 30mph and sounds like he is spinning. So like aj said less than 30mph its probably not gonna be set no 60ft records but I'm not racing this car it's a driver. So please let me know if you have any hands on experience with this(these) cam and again this is completely a respectful post.
 
All you said is true but the op isn't building a race engine, just perking up a 318 on a budget. Hydraulics aren't that bad. Billions of engines have been built with them.
tool, please note that forum member that I replied to was Ottmundr, never stated what the build is, only that he is looking at 3 different hyd roller cams.
The original thread was posted by dartfreak75 the man with the budget 318 which if he has them hyd lifters would very fine.
Please pay more attention in the future before you start pointing fingers.
 
tool, please note that forum member that I replied to was Ottmundr, never stated what the build is, only that he is looking at 3 different hyd roller cams.
The original thread was posted by dartfreak75 the man with the budget 318 which if he has them hyd lifters would very fine.
Please pay more attention in the future before you start pointing fingers.
I actually thought that you was referring to my cam choices also. Cause you said in the post you would go with a solid tappet. It's all good tho I know we all have different opinions about what's good and bad and we all have our own experiences. That's what makes this such a great place to learn so much knowledge and experience and info here to soak up. Thanks for sharing yours!
 
I actually thought that you was referring to my cam choices also. Cause you said in the post you would go with a solid tappet. It's all good tho I know we all have different opinions about what's good and bad and we all have our own experiences. That's what makes this such a great place to learn so much knowledge and experience and info here to soak up. Thanks for sharing yours!
This what happens when people hijack threads, sorry for the confusion, it wont happen again.
Good luck with your project
 
I have a question for the ones of you who say the summit (crane) or whatever it is grind is trash. And let me start by saying that I have great respect for you and acknowledge your experience and knowledge. But have you ever actually ran or drove a engine with the cam or you just saying its trash based on the numbers? Because I have read at least 10 or more reviews with ppl completely happy with it summits website has 3. One of them is a 4x4 360 he even commented on how great the low end torque was. So I'm curious have you had a bad experience with it or you just saying its trash based on the numbers on the paper? I get it the ramp like 74 is not ideal for cylinder pressure the 112 lobe separation doesn't help bottom end either but surely it cant be that bad cause summit still makes and sells these things after all these years. There is one video of a guy running it sounds pretty stout to me you can see the car squat at about 30mph and sounds like he is spinning. So like aj said less than 30mph its probably not gonna be set no 60ft records but I'm not racing this car it's a driver. So please let me know if you have any hands on experience with this(these) cam and again this is completely a respectful post.
I have never run it. It would never be on my radar.
Here is one more deathknell; The total time, in degrees, for all cam-timing events is 720*, plus the overlap. This cam has overlap of (278 +288)/2 less double the 114Lsa =55*.. So that totals 775 degrees. Now you subtract the intake plus exhaust from that and 209* is left over for compression plus power. If you install that cam at 108* to recover some cylinder pressure, this will subtract 113* of compression time, leaving just 96* for to extract power. 96 measely degrees and then the exhaust pops open and pow it all dumps into the headers, still burning, and with plenty of energy in it. And you paid for that energy, when you filled the tank. And now it's contributing to global warming.
With 2.76s, as a streeter,your engine might spend 99% of it's life below 65Mph, which in high gear is a tic over 2200rpm, and in second is a tic over 3200, and in first gear is 5400Rpm.
Now of that 99%, the bulk of it will be spent below 40Mph, which will be a tic under 1400 in Drive, a tic under 2000 in second, and about 3360 in low.
So riddle me this:
1)why would you put a 5500rpm cam into this combo. when the only time it will ever see that is for 1 or 2 seconds at the top of first gear, and for just 1% of it's life. And
2) in the mean time it is using gas like a junky on crack. And
3) the guy in the next lane with an identical car but with a stock cam, a 2800TC, and 3.55s is getting ready to show you his tailights, every single time he takes off, with a 2bbl yet; cuz his combo gets up on the pipe as soon as the tires break loose, and keeps it there to 40/45 mph, and then BAM! he shifts and clobbers you even worse, just when your car with the 6900cam, was getting to the power at 3700rpm.
The numbers rarely lie; they are usually best case
I can tell you exactly how too big that cam is for your combo; remember I said the compression plus power of the 6900 came out to 208*? Well Wyrmrider says that cam is measured at .004, so if you actually measure it and find the durations for .006, so you can compare apples to apples, I'm guessing it would be around 275/282/114. and the math for that says comp+power~214*.. But even if I'm wrong and it's closer to 268/276/114, that still only maths out to 220* comp +power
Your combo wants about 240*, which I would split close to 124/116. Wait where have I seen those numbers before? Hyup the stock 360 2bbl cam. That will get you 17* more on the extraction or plus 17.2%, and plus 11* more compression or plus 9.7%, and 25less degrees of overlap which your combo cannnot possibly make use of anyway,and you can install that 360 cam closer to straight up.
This is a triple win for performance in your combo.
The only downside to the 360 2bbl cam is a total loss of the lumpy idle lope, which really is a just a byproduct of the overlap, which any SBM car that cannot spin the tires and with hiway gears will NEVER make use of more than once if at all, on the way to 65mph. That lumpy idle will cost your combo nothing but tuning troubles and dollars at the pump. And honestly, to hear that 55* you are gonna need to idle it right down, so you better have oil-pressure,and you better be able to tune it, cuz when you put it into gear, your lo-stall is gonna want to drag the engine down, maybe enough to stall it. And if not, then the hesitation that can come when you step on it might. It's just a poor situation. That cam will want to idle, in your combo, at maybe 700 plus rpm, and 55* don't lope much at that rpm. So forget about the lope.

And as someone else already said;
since you are sure to need both gears and a TC with just about any cam, you might as well start with gears and TC, and of those;the TC is the best bang for your bucks. It only takes a couple of hours to install it, and if you don't have the equipment and tools, just save up a lil more and hire somebody who does; it ain't rocket science. On a hoist it's bam-bam and done.

And finally , that cam is not trash.
It's only a bad choice for 2.76s, and a stock 1800ishTC; which the 6900 in an 8/1 teener,will only conspire to bring even lower.
I'm not trashing the cam, I'm only telling you that it will trash your current combo. A 6.1Dcr is pretty flipping low
 
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This what happens when people hijack threads, sorry for the confusion, it wont happen again.
Good luck with your project
I dont feel the thread was hijacked it was all relevant to the topic thank you for your input I really do appreciate it. Thanks
 
This what happens when people hijack threads, sorry for the confusion, it wont happen again.
Good luck with your project
It's easy to start and hard to stop. You guys made some valid points. There's a reason why serious engines don't run juice lifters. I still have a solid in my HP273 and really have no issues.
 
I have a question for the ones of you who say the summit (crane) or whatever it is grind is trash. And let me start by saying that I have great respect for you and acknowledge your experience and knowledge. But have you ever actually ran or drove a engine with the cam or you just saying its trash based on the numbers? Because I have read at least 10 or more reviews with ppl completely happy with it summits website has 3. One of them is a 4x4 360 he even commented on how great the low end torque was. So I'm curious have you had a bad experience with it or you just saying its trash based on the numbers on the paper? I get it the ramp like 74 is not ideal for cylinder pressure the 112 lobe separation doesn't help bottom end either but surely it cant be that bad cause summit still makes and sells these things after all these years. There is one video of a guy running it sounds pretty stout to me you can see the car squat at about 30mph and sounds like he is spinning. So like aj said less than 30mph its probably not gonna be set no 60ft records but I'm not racing this car it's a driver. So please let me know if you have any hands on experience with this(these) cam and again this is completely a respectful post.

A freshly rebuilt 360 with even a factory non-HP cam will "run good". A generic Chevy grind Summit cam will "run good" but pretty much any other cam will run BETTER... This goes for any off-the-shelf cam really, everyone who has one says it "runs great" but they wouldn't really know unless they swapped in a custom-ground cam specific to their engine and compared it back-to-back. If you're spending the money why not get all you can out of each dollar spent?

Also something to consider... while it is a lot of work, it is possible to swap out the cam for another one later on after the engine is in the car. You can get a shorter-overlap cam that works with the tall gears and stock converter for now, then after you upgrade those parts you can get a bigger cam to suit.
 
A freshly rebuilt 360 with even a factory non-HP cam will "run good". A generic Chevy grind Summit cam will "run good" but pretty much any other cam will run BETTER... This goes for any off-the-shelf cam really, everyone who has one says it "runs great" but they wouldn't really know unless they swapped in a custom-ground cam specific to their engine and compared it back-to-back. If you're spending the money why not get all you can out of each dollar spent?

Also something to consider... while it is a lot of work, it is possible to swap out the cam for another one later on after the engine is in the car. You can get a shorter-overlap cam that works with the tall gears and stock converter for now, then after you upgrade those parts you can get a bigger cam to suit.
That's kind of how I see it yes I know it could run better with a different cam I already bought the summit before I knew that and although it could run better I'm ok settling with good just to get it on the road and not steal any more from the budget. Later on if I'm just completely unsatisfied with it I can change it.
 
Howdy,
I built my 318 and run the xe268 cam
However
- alloy heads (65cc)
- block was milled to zero deck
- use kb167 pistons
- ld4b manifold
- hei ignition
- Holley sniper
- Factory 3.23 gears
- stock 904 t/c opened up and modified to about a 2100rpm stall
- comp ratio is about 9.6:1
- use 273 valve train with Toyota Corolla 4K pushrods
Next step will be headers, have some block huggers to go on, not much else will fit due to the steering box (rhd car) and possibly programmable ignition timing to work with the sniper

Car drives really nice, seems most comfortable at about 830 idle rpm, has a nice lope to it



Awesome, it's the exact combo I'm about to screw together for my VG coupe, how do you rate the sniper?
 
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