What cam to use in 340

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gliderider06

gliderider06

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I am currently planning my 340 build for 73 Duster. I will run a 727 (uncertain on converter)3.91 rear and intended fun street use. The 340 is a cast crank and will be bored .020" and a set of 2.02 J heads. I am estimating about 9.75 CR(using the summit calculator) If I don't sell my Eddy headed 318, I might use the heads on that motor. Either way, I will use an RPM intake and 750 holley and headers.
I have several cams to chose from already on the shelf and 2 I would think about buying.
I have a Comp 268 Xtreme 224/230*-.477/.480" 110cl
Erson highflow IH 228/228*-.472/.472 108cl
Erson TQ40 220/228*-.472/.472 110cl
These I don't have, but would buy. Comp nostalga cam 233/240- .474/.474" 110cl and
the famous Crane Cams powermax 222/234*-.467/.494 114cl
I will also be using 1.6 roller rockers, HEI ignition and 2-1/2" duals.
My main choices are the Crane and Comp Xtreme.
Of the ones I listed, what would you run and why?
Thanks folks!
 
If you don't mind buying one, I'd call someone to grind you a custom cam. It's really not that much more money and worth having a cam tailored to your combo in my humble opinion.
 
That Crane is always a good choice. Caint beat the good old Crane magic cam. But honestly, I think you have room for more duration than anything listed and that will equate to more power.
 
Hmmm... RRR That magic Crane cam was run in a 70 340 cuda in high school with 3.91's that ran high 12's all day long. What would you suggest if I were to buy something? I do realize what heads I use may change things somewhat; having smaller chambers and probabally flow a little better than the "J" heads.
 
gliderider06 said:
Hmmm... RRR That magic Crane cam was run in a 70 340 cuda in high school with 3.91's that ran high 12's all day long. What would you suggest if I were to buy something? I do realize what heads I use may change things somewhat; having smaller chambers and probabally flow a little better than the "J" heads.
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PM on the way, sir.
 
How do you want it to idle and sound and how far do you want to rev it?

My guess is that the comp xe268h is a very good choice for your app because it will have a bit of a lumpy idle and should rev to around 5500 rpm but will still pull strong on the bottom because of your gearing.

You will also need better springs than stock.

.
 
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barnett468 said:
How do you want it to idle and sound and how far do you want to rev it?

My guess is that the comp xe268h is a very good choice for your app because it will have a bit of a lumpy idle and should rev to around 5500 rpm but will still pull strong on the bottom because of your gearing.

You will also need better springs than stock.

.
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You might want to check out the Hughes Engines website. Dave Hughes has been specializing in Mopar engines for years and really knows what works for a particular application. Tell him what you need and he'll supply it or give you a custom grind.
 
lroman said:
You might want to check out the Hughes Engines website. Dave Hughes has been specializing in Mopar engines for years and really knows what works for a particular application. Tell him what you need and he'll supply it or give you a custom grind.
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Try Jim at Racer Brown for a custom grind on a 340 ....
 
call some custom grinders and I bet they say around 222-228 intake and 226-232 exhaust and 110 lsa. use the comp cam U have installed at 105*-107* and do some port blending on the J heads. 9.75 is no problem with pump gas
 
280/474 mopar purple cam. Have in my 360 goes good and strong. Then again a 9.5 3400-3600 converter and 3.55 gears help bring it all together!
 
Xe268h in that engine with a good tune up will make right at 335-350hp.
 
The Eddie heads will accept lifts to .600 or so. Aluminum heads need more compression, and 1.6 arms will jump the lift up 6%, and a cam around 270/276 with matching CRs will really haul . Hughes has some hi-lift fast-rate cams.There may be others.
 
AJ/FormS said:
The Eddie heads will accept lifts to .600 or so. Aluminum heads need more compression, and 1.6 arms will jump the lift up 6%, and a cam around 270/276 with matching CRs will really haul . Hughes has some hi-lift fast-rate cams.There may be others.
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I'm not a big fan of aluminum heads. Other than weight I see no advantage to running them. A good set of Iron Ram or similar iron heads when bowl ported and blended, some 2.02 intakes, and a good gasket match on the ports will give you all you need without spending the money or taking a compression lose. With me it's all 'bang for the buck'. I'm also very proficient with a die grinder. It's all a personal choice. I've read several times about someone being disappointed after spending the money for aluminum heads and not getting the performance they were expecting. I like to get the best results without draining my pocket book.
 
Yabut
It costs money to run .600 lift in the old LA heads.And it gets all too easy to make too much compression with iron, on a 360. Otherwise I agree. I wanted to run 87E10, so iron was out.And I wanted to run up near the .600 limit, so stockLAs were out. And I wanted to explore the "tight quench" theory,so again LAs were out. And the LA exhaust ports cost a lot of money to get up to speed. And back in 99 there were not a lot of options. The Eddies hit the market at just the right time, so I jumped in.
Running 87 has saved me thousands of dollars over 16 years. Tight Q and aluminum has let me run up to 11.3Scr. And a 230* hi-lift cam motorvates the old S to 93 in the eighth. I just bolted those heads on.
Today in 2016, there are plenty more options for sure. And I think I would try iron if I had it to do over; but at age 63, I think I am done with going fast. I'm thinking of resurrecting my 80Volare/slanty,lol.
 
My plans so far are to use my "J" heads unless the Edelbrock headed 318 I'm selling does not sell then I will rob most of that engine for the 340. As the cam goes I'm torn. I have gotten some great suggestions and a friend of mine is trying to convince me to go solid or even roller, but he is not the one spending the money to build it. I have some more figuring out to do.
 
Lunati voodoo 268 is another really good street cam

Old number was 60403.
 
In stock form, the J heads can run 13's without to much effort and into the 12's & 11's properly ported. Running faster than an 11 with a OEM head will require a fully ported head and a very light eight car. Not to mention some other parts that are probably not so desires me for the street.

I like my Edelbrock heads. They made it easier to perform at higher levels quicker than a OEM head.

Bang for the buck wise, a lot depends on what your doing with the car, what you can do rather than pay someone with and the abilty to wisely use what you have to the best possible outcome.

A ported OEM head that can go 250 cfm has the abilty to make an easy 450hp and the power to run quickly. Lighter weight cars run quicker than heavier ones.

Off the soap box now.....
 
a solid roller is a complete waste of money on iron heads . the entire point of a solid roller is to be able to make a very aggressive profile that opens the valves extremely quickly and unless you have heads that flow a ton of air, you will not be able to optimize the benefits of one . the key to hp is in air flow . if you don't mind adjusting valves and having a noisy engine, you could run a flat tappet solid cam and save yourself around $400.00 . if the heads are not ported, you might be able to find someone that will do some basic bowl blending and valve guide profiling for around $700.00 . this will include regrinding the valves and seats . they can check the guides at the same time . if the springs are stock you will need new springs for around $120.00.

if you like to rev the engine and dont already have an intake, i would run an air gap instead of an rpm.

if you use a solid flat tappet cam, i would use the howards cams lifters with the oil hole in the bottom.
.
 
Of the choices given, I like the XE268. Big cams like high compression. Generally speaking aluminum heads are better for high compression as they will tolerate more heat before detonation occurs. If it were me and this was my #1 car, I'd pull the Eddys off the 318 and use 'em on this motor.
 
AJ/FormS said:
Yabut
It costs money to run .600 lift in the old LA heads.And it gets all too easy to make too much compression with iron, on a 360. Otherwise I agree. I wanted to run 87E10, so iron was out.And I wanted to run up near the .600 limit, so stockLAs were out. And I wanted to explore the "tight quench" theory,so again LAs were out. And the LA exhaust ports cost a lot of money to get up to speed. And back in 99 there were not a lot of options. The Eddies hit the market at just the right time, so I jumped in.
Running 87 has saved me thousands of dollars over 16 years. Tight Q and aluminum has let me run up to 11.3Scr. And a 230* hi-lift cam motorvates the old S to 93 in the eighth. I just bolted those heads on.
Today in 2016, there are plenty more options for sure. And I think I would try iron if I had it to do over; but at age 63, I think I am done with going fast. I'm thinking of resurrecting my 80Volare/slanty,lol.
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You may have misread me. You're referencing the LA heads. I got rid of any LA heads I had in the 90's. Ever since the Magnum heads were introduced. From everything I've always read, the Magnums will outflow the LA heads right out of the box eventhough they have the smaller intake valve. The discovery of the cracking of the valve seats led to the development of the EQ (Iron Ram), RHS, FA and other aftermarket iron heads. The light port work , gasket matching, and 2.02 intakes was what I was referring to. Of course the pushrods and rockers are part of the swap. The minor drawback is the limited intake manifold selection. They're out there. You just have to search them out. The racing heads are a whole different story. Now you're talking the W series heads or Brodix or B1-BA heads. Want port work ? Cha Ching.....there goes the budget. Big cams, heads, special valve gear, intakes, headers, fuel systems....etc.?? Did someone say turbos ??? You know where I'm goin' here. It never ends. How much do you want to spend ?? You mentioned you're 63. Congratulations, we both made it past 60. I'll be 69 in 2 weeks. Now retired with the car fever still glowing bright. You completely understand what I'm talking about. Too bad you couldn't see the big grin on my face when you mentioned the old 225 slant six. I grew up in a racing family. Motorcycles, snowmobiles, cars. Love engines. Spent 4 year in USAF. Worked with 2 stroke, 4 stroke, rotary, radial, opposed, and diesel. Worked in alternative fuels while running an engine development dyno at the Ford Research/Engineering Center. Whew....I'm getting carried away here. I guess I'm talking too much. TMI. I'm getting older and have a garage full of car stuff. My 2 boys take no interest in the car culture. I'm just trying to get rid of as much as I can in case the Creator pulls the plug on me early. I don't want to leave them a big mess to deal with. I don't want my parts ending up at the scrap metal yard either. Nice talkin' to ya eh.
 
I don't know how much a Magnum head can handle as far as lift is concerned in stock or worked over form. As cast, be it Magnum or LA head, once the porter takes over, it is all a wash on what is better or not since the combo of the engine and intended purpose of the engine and what the builder takes advantage of is another story.

IF I was to do another iron headed engine, it would be one of two ways.
Dead stock/very mild hop up or a W2 to go make some power with. That's it.

Glideriders build meets mild hop up. With or without porting the iron. It's on track to be a nice power plant.
 
Ironman
Sheesh this thread is hard for me to follow. I was responding to your post, thinking you were the OP;gliderider;
who is thinking of going Js,that he's already got, instead of the Eddies that he also already has. If I was stuck in that place, with the short block not yet built, The Eddies and 11/1 would be a no-brainer for me.
The highest point in Deleware is 447 ft, so let her buck.
Sorry for my confusion.

My 2 boys take no interest in the car culture. I'm just trying to get rid of as much as I can in case the Creator pulls the plug on me early. I don't want to leave them a big mess to deal with. I don't want my parts ending up at the scrap metal yard either. Nice talkin' to ya eh.
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This I also can relate to('cept just one son). We should all get together and build/buy a large centrally located warehouse , and deliver all our stuff there. I could sure use the room around here. Then hire a couple of guys to refurbish the stuff and sell it all. For me it's not so much about the money, as finding a home for it before the Creator comes for me.
 
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