Comp cam XE262 in a 340

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bill340S

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I'm looking for feed back on the Comp Cams XE262 as compared to the popular XE268 in a 340. If your trying to torgue up a 340 the XE262 seems a better choice to me based on spec's and comp cams free online dyno graph. My engine is 9.5 compression with stage one X heads. Anyone used this cam?
 
What is a stage one X head?

I have run similar cams (spec wise) from other companies and the 218*@.050 duration of the 262 starts power around 15-1800. A bit lower than the 224@.050 of the 268. Which is a duration indicative of a street performance cam. (1st style)

The smaller cam will make more torque and hold HP to approx. 5/5500. It's a good cam for a total driver with some decent torque and HP.
 
rumblefish360 said:
What is a stage one X head?

I have run similar cams (spec wise) from other companies and the 218*@.050 duration of the 262 starts power around 15-1800. A bit lower than the 224@.050 of the 268. Which is a duration indicative of a street performance cam. (1st style)

The smaller cam will make more torque and hold HP to approx. 5/5500. It's a good cam for a total driver with some decent torque and HP.
Click to expand...
Thanks rumblfish360. "stage one" is a term used by engine builders when referring to minor porting of heads. For instance, a simple pocket porting job. Typical Stage two would be further porting into the runners or increase in valve size either one or both valves. Gasket match, etc.
 
And that's why I ask because your stage one is know as a bowl ported head and that's it unless there is something else hidden or simply not done.

In other words, "Stage 1" heads mean jack squat because of the variance in work between builders/head guys.

No one has the same "Stage 1" work and everybody loves throwing these unreliable terms around like they mean something.

Minor porting is even Pretty vauge. Bowl
Ported is not minor work. Even on aluminum that's easy to carve on.

Your stage 2 description indicates 2 different aspects of work totally different from each other. And combo dependent, should be done together
Or left alone as separate jobs.
Not ether or both.

If I followed your descriptions, ...
I'd have stage 8 heads here & stage 9 there. (Below ;) )

IMG_0097.JPG
 
The stock 340 cam is about even with the 250 cam in that line. So the 262 is 2 steps up so about 30-40 hp increase. Looks like a good match.
 
What's the goal with the said cam?
If the X heads are pocket ported (or AKA bowl ported) it will increase out put by 20+ HP and similar in TQ. It'll be a nice driver with some power. Probably run low 14's to high 13's depending on equipment. IMO, it'll be easy going and enjoyable at the same to me.
 
OH! What 273 said!
And .... the replacement performance 340 cam is about the 268.
(224 vs 228 @.050)
 
rumblefish360 said:
What's the goal with the said cam?
If the X heads are pocket ported (or AKA bowl ported) it will increase out put by 20+ HP and similar in TQ. It'll be a nice driver with some power. Probably run low 14's to high 13's depending on equipment. IMO, it'll be easy going and enjoyable at the same to me.
Click to expand...
No racing intended. I had the shop rebuild the 340 to 9.5 static compression and had the hardened exhaust rings installed in addition to stainless valves for todays crappy fuel. I'm old school and we always called it pocket porting years ago. But now folks say "bowl ported". The plan was to gain back thru the head work what I lost with the compression reduction. So, thanks for "20+ HP" estimate.
 
rumblefish360 said:
And that's why I ask because your stage one is know as a bowl ported head and that's it unless there is something else hidden or simply not done.

In other words, "Stage 1" heads mean jack squat because of the variance in work between builders/head guys.

No one has the same "Stage 1" work and everybody loves throwing these unreliable terms around like they mean something.

Minor porting is even Pretty vauge. Bowl
Ported is not minor work. Even on aluminum that's easy to carve on.

Your stage 2 description indicates 2 different aspects of work totally different from each other. And combo dependent, should be done together
Or left alone as separate jobs.
Not ether or both.

If I followed your descriptions, ...
I'd have stage 8 heads here & stage 9 there. (Below ;) )

View attachment 1715005597
Click to expand...
Thanks for the lesson, I think. Yes, my heads were bowl ported. They were cc matched (68cc) and hardened exhaust rings installed. All separate jobs. The head builder called it a stage one. I agree no one has the same stage one work. But most gear heads understand that when someone says stage one it generally means the first basic step in head work like opening up the bowls.
 
Comps' on line dyno uses a 9.5:1 356 sm blk with Dart heads and holley 3310 and shows about 348 hp at 5300 rpm outperforming the XE268 at that level with more torque as well.I considered this cam but i think there will be detonation issues at 9.5:1 compression w / iron heads.
...maybe the 268 .224 / .230 or even better the lunati 268 .226 / .234 would be better at 9.5:1?
 
Last edited:
I also think the cam is small for the ratio at hand but it is do-able with careful timing.

Most people around here that state "Stage 1" porting are instantly put into the "know nothing" category. Be it young or new, I don't fault them.
I just get annoyed at companies that run this title for there work.

Back in the day, we also called it pocket porting.
 
I'm going to list that cam for sale here within the coming week ( Comp XE 262 H ) cam lifter package new in box.
I've decided to stay closer to stock, no special stall convertor and keep the power brakes. So I wont be using this cam.
 
I put a hi-lift 223*@050 cam in my 360 @ 10.9Scr(alumunum heads) and it was fantastic!
Mega torque. Fantastic fuel mileage, great streetpower.
With proper springs, reved to the moon and pulled hard a good long ways with Eddies.
Best street-combo I had.
Current 230* cam is only modestly more fun at the top.

Your 340 with less stroke and the modest compression will need great care in cam selection.A little too small and the cylinder pressure/squish will drive the engine into detonation. A little too big and the same thing could happen with the addition of the soggy bottom-end.
IMO,the 262 is a really great off-the-shelf compromise, delivering about 7.93 Dcr@158 psi. Personally, I would try to find a slightly-bigger, much-higher lift, custom cam, to take full advantage of your combo. Something like the smallest Lunati Voodoo P/N: 30200740.

Solid Flat Tappet. Excellent hot street/strip cam with great torque and HP from low to high end. Needs 2500 RPM stall converter, headers, 10:1+ compression, 3.55-3.73 gearing. Lopey idle.
  • Advertised Duration (Int/Exh): 264/272
  • Duration @ .050 (Int/Exh): 235/243
  • Gross Valve Lift (Int/Exh): .525/.546
  • LSA/ICL: 110/106
  • Valve Lash (Int/Exh): .016/.016
  • RPM Range: 2400-6600
  • Includes: Cam Only
This will have the very same 58* ICA, and so the Dcr will remain the same at 7.93. But this is a Ripper of a cam. For the very same Advertised, you have a potential to make maybe 20/30 hp more, if the heads can keep up.Headers are sorta mandatory. If you are committed to manifolds, I would pass on something like this.
I'm not suggesting that you install this exact cam. I'm just showing what can be done with the exact same ICA. Call your favorite cam grinder and follow his advice.
 
Last edited:
Kinda comparing apples to oranges but:
I have a comp 262 roller in my truck.
360 mag with 10.81 static compression.
It has 15 in/hg so no issue with power brakes.

I also have a Luntini voodoo 703 in my 340 duster with stock x heads.
It has 8.98 static and also has good vacuum, I dont remember the exact reading.
I do not have power brakes on this car but I don't believe it would be an issue.

Both vehicles are 4-speeds.
 
sireland67 said:
Kinda comparing apples to oranges but:
I have a comp 262 roller in my truck.
360 mag with 10.81 static compression.
It has 15 in/hg so no issue with power brakes.

I also have a Luntini voodoo 703 in my 340 duster with stock x heads.
It has 8.98 static and also has good vacuum, I dont remember the exact reading.
I do not have power brakes on this car but I don't believe it would be an issue.

Both vehicles are 4-speeds.
Click to expand...

how does the 703 perform in your 9:1 340 and what gears?
i'm looking at the 703 right now.
 

Buddy has a build just like yours. He runs a voodoo 702 I think it is 220 and 226 at .050 and .475 and .494 . Car runs strong and has good torque. Has a small lope at idle. His car does have 3.55s and a 3 speed with over drive so I cant comment on how it is with a stock converter.
 
ir3333 His compression is 9.4 to 1 He called lunati and this is the cam they suggested he use. He is very pleased with it.
 
I think RRR recommends the xe262 for 318's too. Good off the shelf cam for stock small blocks.
 
ir3333 said:
how does the 703 perform in your 9:1 340 and what gears?
i'm looking at the 703 right now.
Click to expand...


It is a little low on off idle torque, but I have 3.23 in the car now, not too bad but my tires are 275/60/15 so not a great combo to begin with a straight 4-speed.

I do have a fresh set of 4.30 gears I put together just for the combo.
Its just a weekend toy, with no highway driving.

I do really like the comp 262 in my truck, it pulls hard right off idle, it is my pulling truck, so either the bed has a load in it or a trailer hooked to the hitch.
The truck has 3.55 gears and 235/75/15 tires, it really pulls hard.
 
Sireland, I agree, JUST off idle! (But it is passable with a stock converter.)
More gear or less tire. That will fix it. 3.23's is as low as I would go. I had a 3.21 gear and stock tires. It worked well.
 
rumblefish360 said:
Sireland, I agree, JUST off idle! (But it is passable with a stock converter.)
More gear or less tire. That will fix it. 3.23's is as low as I would go. I had a 3.21 gear and stock tires. It worked well.
Click to expand...

It is defiantly drive-able, but my wife plays with my toys once in a while, and she is picky.
Throwing more gear at it was the plan before I used the cam.

She did complain with the truck though, she said it would be worthless in the winter. (too much power).
 
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