Comp Cam XE274H

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71duster06

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Has anyone used this cam. Im looking for how your car ran with it. Rough or smooth idle, good RPM range (actual street feel), and if you needed to change the valve springs along with it. I already have the stock double springs on my 340.
 
I have the XE268H on my 360 and it idles almost as smooth as a stocker so the XE274H will be lumpier and lumpier again with the smaller displacement engine, certainly streetable though.

You will definately need new springs. The stock 340 springs are single with a damper. Comp recomends double springs for this cam.
 
The xe274h is what I have. I like it a lot. Its in a 340/416, stock X heads (had to change the valve springs) and about 9.5:1 compression, headers, airgap/eddy 750, and a 4 speed. It sounds lumpy at idle but makes plenty of power from idle to at least 6000 rpm. Its a great street cam, especially with the stroker crank. If I were to spend any more time at the track, I think I would go up a step to the xe284 or maybe something from the high lift series.

I had the xe268 before the current setup in a stock 340 with the 340 exhaust manifolds and that ran really well also. Its a big imporvement over the stock cam.

Let me know if you have any specific questions.
 
I have the XE274H in my fresh 340. It's is a tad rough at idle (but sounds great) and gives quite a bit more hp than the stock 268. I had to use different springs.
 
I ran it in a 360 with 8.7 compression,it had a good sound at idle but wasnt to lumpy,I ran 16 initial,vaccum was 11in. and it made really good power.I ran single w/dampner for $40 (elgin springs) and set them up for 110 on the seat and 280 open,they worked great.
 
Could you guys give the part number for the springs you used? Did you go with what Comp Cams recommended?

Call Comp Cams and them what heads, valves and cam you are going to use and they will give you part #s for springs, break-in lube, seals and locks. You will want to break in the cam with only the outer spring then after a few miles, install the inner springs also. You can buy the parts from them or go to Summit/Jegs or whatever you like.
 
here was my XE268 in my 318, so the XE274 should sound better

[ame="http://www.youtube.com/watch?v=FwlWTxJFlro"]YouTube- The Dakota[/ame]
 
Could you guys give the part number for the springs you used? Did you go with what Comp Cams recommended?

My springs were COM901-16 but as was stated I would also strongly recommend getting Compcam's recommendations for your specific build. My build with the 274 got me around 400 hp and 405ftlbs.
 
Comp recommends their spring # 995-16 for it. I had it in my 360 at first but kept having lifters go bad. Not flat, but bad as in they would no longer pump up. This was about 3 yrs. ago when comp was having lifter problems due to their US lifter mfg. being on strike and buying Chinese lifters. They have it all straightened out now but at the time I got tired of the junk lifters and pulled it out and put a Lunati in. As far as how I liked the cam it ran great and pulled strong to 6000+ and I even took it to 6500 a couple times and it was still pulling good. I had 4:10 gears and a 3000 stall at the time and serious traction issues so I don't know for sure what it'd run but I think it would have been right at 13 flat to possibly high 12's. My car is kinda heavy at 3660 with me in it. Definitely a good street cam. The idle was choppy but not radical by any means.
 
Comp recommends their spring # 995-16 for it. I had it in my 360 at first but kept having lifters go bad. Not flat, but bad as in they would no longer pump up. This was about 3 yrs. ago when comp was having lifter problems due to their US lifter mfg. being on strike and buying Chinese lifters. They have it all straightened out now but at the time I got tired of the junk lifters and pulled it out and put a Lunati in. As far as how I liked the cam it ran great and pulled strong to 6000+ and I even took it to 6500 a couple times and it was still pulling good. I had 4:10 gears and a 3000 stall at the time and serious traction issues so I don't know for sure what it'd run but I think it would have been right at 13 flat to possibly high 12's. My car is kinda heavy at 3660 with me in it. Definitely a good street cam. The idle was choppy but not radical by any means.

What setup did you have in your motor? Sounds close to what I have so far performance wise.
 
The xe274h is what I have. I like it a lot. Its in a 340/416, stock X heads (had to change the valve springs) and about 9.5:1 compression, headers, airgap/eddy 750, and a 4 speed. It sounds lumpy at idle but makes plenty of power from idle to at least 6000 rpm. Its a great street cam, especially with the stroker crank. If I were to spend any more time at the track, I think I would go up a step to the xe284 or maybe something from the high lift series.

I had the xe268 before the current setup in a stock 340 with the 340 exhaust manifolds and that ran really well also. Its a big imporvement over the stock cam.

Let me know if you have any specific questions.

What time was you 416 xe274H running at the track. What gears and rear tires did you have?

What did you old xe268 combo run?

So the 416 xe274H combo was noticablity lumpier than the 340 268 combo you ran before?
 
What setup did you have in your motor? Sounds close to what I have so far performance wise.

360 bored .030 and balanced. 9.8 to 1 compression. X heads I ported that flowed 251. Hooker 1-5/8 headers. Eddy Air-gap. 750 holley vac secondary. 3000 stall. 4:10 gears.
 
What time was you 416 xe274H running at the track. What gears and rear tires did you have?

What did you old xe268 combo run?

So the 416 xe274H combo was noticablity lumpier than the 340 268 combo you ran before?

The 416 xe274h went 12.8 @109 with 3.55 gears and 255/60 ET Streets. Hopefully it will go faster with a better launch. The tires were on rims that were too narrow and not working the best possible. This year, I'm going from 7"rims to 8", putting the original 3.91 back in and changing the Eddy 750 to a Holley 750dp.

The 340/ex268 was much closer to stock, including exhaust manifolds. With 245/60-14 street radials and the 3.55 gears it was going 14.5 @just about or under 100.

The ex274 setup is noticeably more lumpy but still very good at low rpms. I'm suppose a lot of that has to do with the longer stroke. The car has no power anything so vacuum is not really a consideration.
 
building a 340 bored .030 edlebrock aluminum heads, air gap manifold and comp cam 275 xtreme hi-lift cam .525 lift and edlebrock 650 carb Hope it does good. Hoping for choppy idle and lots of power
 
I have a XE284 in my 318 and it idled pretty crappy...
1971 Dodge Dart Swinger 318 exhaust vid with hooke

But that was a low compression 318 so with a decent 340 I think a 274 will idle pretty smooth, small amount of lope, and have good vacuum. Every combo is going to be a bit different. And you should definately go with the springs that Comp cams recommends for that cam, so that the spring rate matches the lobe pattern.
 
418 STROkER 10.2 comp, eddy heads, comp XE275XL, air gap with an edelbrock 750, TTI headers, right now I fighting with getting the timing/advance dialed in . It is definately a very angry engine with TONS of power and a very aggressive lope when I can get it to idle correctly.
 
A)

The 416 xe274h went 12.8 @109 with 3.55 gears and 255/60 ET Streets. Hopefully it will go faster with a better launch. The tires were on rims that were too narrow and not working the best possible. This year, I'm going from 7"rims to 8", putting the original 3.91 back in and changing the Eddy 750 to a Holley 750dp.

The 340/ex268 was much closer to stock, including exhaust manifolds. With 245/60-14 street radials and the 3.55 gears it was going 14.5 @just about or under 100.

The ex274 setup is noticeably more lumpy but still very good at low rpms. I'm suppose a lot of that has to do with the longer stroke. The car has no power anything so vacuum is not really a consideration.

B)

418 STROkER 10.2 comp, eddy heads, comp XE275XL, air gap with an edelbrock 750, TTI headers, right now I fighting with getting the timing/advance dialed in . It is definately a very angry engine with TONS of power and a very aggressive lope when I can get it to idle correctly.

Thank you both very much for posting your combos. Those seem very close to each other for comparing those two cams. Out of those two, I think the XE274H is more for me and the 408 stroker I'm envisioning. I have a vehicle for work, but other than that my Barracuda is my transportation. So it does get driven a lot. I'm going to go to the grocery store right now in it at 10:30pm.

684mulas, what compression are you running? Can you run crappy 91 octane gas in it.

684mulas and 418 STROkER what stoker kits or parts did you choose; what brand crank, rods, pistons?

Did you run the E-brock heads out of the box?
 
684mulas, what compression are you running? Can you run crappy 91 octane gas in it.

684mulas and 418 STROkER what stoker kits or parts did you choose; what brand crank, rods, pistons?

[/QUOTE]

The compression should be about 9.5:1 so it runs fine on pump gas. Basic Mopar electronic ignition too. I used the Scat forged crank with I beam rods and KB742 (think thats the #) pistons. Nothing too crazy because its primarily a street car. I wanted it to be dependable, drivable and still be able to go into the 12s. I also have a 3.23 setup for longer trips, like going to Carlisle.
 
Mine was built by SPEEDOMOTIVE, I know mine has diamond pistons, the heads were worked a little but could probably go a little further. I am trying to get it dynoed this week moybe next to see where it is at.

- 4340 FORGED 4.000" STROKER CRANKSHAFT
- FORGED 4340 6.123" H BEAM CONNECTING RODS
- FORGED DISH-TOP PISTONS
- JE PLASMA MOLY FILE-TO-FIT RING SET
- CLEVITE H SERIES MAIN & ROD BEARINGS

COMPRESSION RATIOS:
60cc = 10.3:1, 65cc = 9.8:1, 70cc = 9.5:1
 
684mulas, what compression are you running? Can you run crappy 91 octane gas in it.

684mulas and 418 STROkER what stoker kits or parts did you choose; what brand crank, rods, pistons?

The compression should be about 9.5:1 so it runs fine on pump gas. Basic Mopar electronic ignition too. I used the Scat forged crank with I beam rods and KB742 (think thats the #) pistons. Nothing too crazy because its primarily a street car. I wanted it to be dependable, drivable and still be able to go into the 12s. I also have a 3.23 setup for longer trips, like going to Carlisle.[/QUOTE]

What are you running your timing at? I have the basic mopar electronic ignition as well and I have been messing with different settings and haven't got it dialed in quite yet.
 
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