What cam?

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sublimeswinger

SUBLIME Senior Member
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I have a 68 318. Im gonna put a eddy intake,probally a preformer,and a 750 eddy carb. I want to change the cam but want to keep the rest of the engine stock. What duration or cam would you guys suggest?What brand?Are Mopar purple,crane or eddy all the same?
 
You will also need to replace your valve springs, and it's a good time to stick some fresh valve seals on and a new timing set and fuel pump eccentric at the same time. I'd also caution you, always lean towards the smaller cam. You can very easily overcam that 318, making it at best a dog, and at worst bending valves or pushrods. I would install an XE262 Comp. I dont use MP cams unless I'm forced to for quality control, or should I say lack of quality control issues with them.
 
The 750 is going to be too much carb for a basically stock 318. You will be much happier with a 600 or even the 500. Just like the cam you are better off to error on the small side.

The Eddy performer cam will be OK definately not the performer rpm. The Comp XE262 would be a very good choice to.
 
like dgc333 said i also think that 750 is a little to much for a 318 used to drive a 318 with some cheap headers, a 600cfm edelbrock a edelbrock performer manifold and a compcams cam cant remeber wich one think it had 268degres of intake duration, it ran real good but the cam was a litle to big and didnt have so much torque would probably go for the XE262 like moper and dgc333 sugest if i did it again!
 
Sublime, look at Comp par tnumber 20-222-3. That's Comp's p/n for the cam named the XE262. Follow the recommendations for the 901-16 springs, and it may be cheaper to get the cam and lifter kit as opposed to parts seperately, which would be K20-222-3.
 
moper makes a good suggestion.
I would not use a Edelbrock cam. IMO, you can do better. Edelbrocks advertisment of matched componets is to make things easy for those not knowing alot about matching componets. Though not a bad choice for adding torque, theres better cams to suite the needs. Edelbrocks problem is to walk the thin line of not to much cam but enuff to make a nice improvment.
It's a catering to the mass' thing I think.

I am doing a Duster project now.
http://www.forabodiesonly.com/mopar/showthread.php?t=10508
It is powered by a stock '79, 318. This is a lower compression engine than earlier 318's. The low compresion is a minor problem. But it can be made worse by wrong cam choices.
Whats your gear ratio?

My choice is a Crane cam. It may not have as an aggressive lift as the Comp cams XE line, but it also has a wider centerline @ 112 to help build cylinder pressure. Theres not a big difference in 2*'s of lobe seperation, but every little bit helps.
The current specs are 272/284 advertised duration, (@.050 is 218/224 I believe) with .454/.480 lift. Also Crane springs that are for the cam. The rest of my build up, bolt on parts are a old Edelbrock LD4B (Dual plane) intake and a AVS (Small), headers. 904 trans and a 8-1/4 w/ 3.21 gears.

Later down the road, I will do a light mill of the heads for a better ratio that will work with the cam better. As well as a little prep work on the head.
 
Whats your gear ratio?

i will be installing a 8 3/4 rear with 323 gears.i would like to change these to 355 or 391 but im not sure when.This stuff gets exspensive.I want good tork off the line,spin tires when i want. I will be also installing a 727 tranny.I would much rather have a 904 i think , but im getting a good deal. I have decided not to put to much into this motor in hopes of upgrading to the 360/390 hp crate motor someday.
 
Rumble, why use an old manifold? are they better than the preformer?
You have always given me great advise/help and i really respect your opinion.
Thanks. Do you happen to know a part # for the crane?


Anyone else with suggestions?
 
LOL @ this. When I got my Dodge Magnum, the owner (1st and only to that point) had used the Perfromer package in full on the 318. I resold the intake with everything for a bolt on and go and glass beeded (Which I can do at work for free) for $125. That and a few other parts not needed then powered the DODGE project foward.

Since I'm now driving the Magnum, daily, I got board and needed a project. Loard knows what a pain it is to fix/restore a daily driver so I got the Duster and used the, yep, you guessed it. What is laying around the garge floor without an intake or carb.

There was also alot of buzz here awhile back on what to do to my 318 with the most popular answer of get a bigger engine, which isn't allways the best finacal thing for some people. So I started this "Rumblefishs duster" project thread. And decided to use the 318 and show what coulod be done with it.

Now this "On The Cheap Project" thread is just that with few brand new parts and alot of "Off My Shelf Parts" to make it go.
The intake was for it's time top notch and the ol'Direct Connection pointed the "OK" finger to that intake as "The One To Use For Your 273/318"
A buddy MoPar crazy guy I work with had one sitting. $60 and shes your.....I'll be right over I said.

Though I would prefurr a Performer and ThermoQuad combo just for the T-Q alone, theres no promise of better performance though I believe there would be. For surley in mileage, but then again, start chaing cams and......mileage goes down anyway.

I'm having a problem with the computer the last 2 days. Just go to Crane cams or Summit/Jegs racing sites and do a search for Crane cams and match up the specs. I have apicture of the cam box with the specs in my thread.
 
sublimeswinger said:
Whats your gear ratio?

i will be installing a 8 3/4 rear with 323 gears.i would like to change these to 355 or 391 but im not sure when.This stuff gets exspensive.I want good tork off the line,spin tires when i want. I will be also installing a 727 tranny.I would much rather have a 904 i think , but im getting a good deal. I have decided not to put to much into this motor in hopes of upgrading to the 360/390 hp crate motor someday.

The above cams, Comp or Crane will deliver the power you'll need to do just that with 3.23's and a higher stall converter would be a real nice help in spinning tires or just simply, a better launch into you power band.

I myself would yeild @ 3.55's for street duty while driving the car often. 3.91 would just fine for the track with increased performance parts and mods. IE milled and ported heads, larger exhaust, set up suspension, sticky tires etc.... you know the drill.
 
I was curious about the comp 20-222-3 cam. My heads were rebuilt with Mopar dual spring valve springs. I also have new hyd. lifters. With the cam, is there any difference between the recommended springs with the cam or will mine work fine. Also, do you recommend their lifters. thx
 
Eric, What valve springs from MoPar do you have? There could be a huge difference in spring rates.
How's lifters? MoPars?
 
I can't find the info on the springs and lifters. The lifter box shows ha 2011. Is there a way that I can measure the springs to see what they are? This is little info, but I'll do some more measuring and see if I can see what rate the springs are.
 
You can measue there height and width unsprung as well as wire diameter. But the true measure of the spring will be in the amount of pounds the spring is at there installed height and near coil bind.
I'm not exactly sure were the best place to get a reading is.
Oerhaps an engine builder or racer would know this better.

The problem with this mystery spring is it could have to much pressure on the cam and wipe it out.
Not enuff and you would have valves floating. (Poor RPM ceiling)
 
I always prefer the stock 340 replacement cam for 90% of my 273-318 performance builds, has lots of low end grunt, great mid range+ good top end power....kim
 
I put 3.23 gears in my otherwise standard 318 plus the XE262H Comp cams set up. It made an immediate change without compromising the drivability of the car. These cams make power from 1200-5200rpm. Worked for me and I used all Comps matching parts inc timing gear.
 
I found the springs that were installed they are from Summit

DCC-4120249 $6.88
Estimated Ship Date: Monday
Application Warranty Show All

Brand: Mopar Performance Parts
Product Line: Mopar Performance Valve Springs
Number of Springs Per Valve: Single
Outside Diameter of Outer Spring (in): 1.497 in.
Damper Spring Included: Yes
Inside Diameter of Outer Spring (in): 1.078 in.
Inside Diameter of Inner Spring (in): 0.990 in.
Valve Spring Style: Standard
Coated: No
Quantity: Sold individually.

Valve Spring, Single, 1.497 in. Outside Diameter, .430-.500 in. Lift Range, .206 in. Wire Diameter, Each
 
Those MoPar springs have a rated lift of90 lbs. @ 1.67 spring height (Closed) and 230 lbs. @ 1.27 (Open)
The Comp 20-222-3 is the XE262H with a .462-.470 lift.
Comp recomends there 901 spring. (The -16 is amount of springs as in 16 for the V-8 engine.)
The spring specs as per catolog are;

1.494 outer spring w/damper
I.D. 1.040
spring seat load; 101 @ 1.650
open load; [email protected]
coil bind 1.160
rate/lbs/In. 353

By compare, the MoPar spring is approx. 12 lbs. light. It could be used though max performance would be with the Comp spring. The lighter spring would cause early rpm valve float. Now how much 12 lbs. will effect it's performance and rpm ceiling before valve float is something I can not answer.
 
OK I really need HELP NOW.


I talked to Summit about the comp cam kit k20-222-3

They said i will need to mill the heads so the springs will fit. WTF? Is this true?
I didnt want to take the heads off nor did i want to spend extra money (which i dont have) on them.

My springs measure 1 3/8 (i think) and he said i would have to have it milled for 1 1/2.

am i over reacting? is this a big deal? does he know what hes talking about?

p.s. He also said the mildon windage tray wont fit my stock pan....Is this true?

I want to order this stuff....any help would be appriciated A.S.A.P

Thanks
 
Machining the spring seat is comon practice with the after market cam company's springs.
Not so with the single MoPar spring. (249 spring on the 1st page)

I do not know about the windage tray.
 
Thats the proper spring to use. I don't know if the spring seat needs work for them to fit on the head.
 
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