Which heads wpuld be better?

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hmm and the price for all that doesnt even seem all that bad, if u lucky in finding some ofthat stuff in the junkyard that is not cracked or anything. would that on some weight reductions and tuning my suspession properly put me at the low 12 1/4 time im looking for?
 
I think so. However, like you said, finding a junk yrad engine thats in great shape will take some serious hunting and luck. Thats why I said when you do a good short block as opposed to making use of a seasoned one or the even rarer junkyard jewel.
I don't think you'll need a bigmech. cam and 4,56's to get there, but a well exacuted plan you'll need.
Lightening up the car is a great way to help.
 
see the 318 that is in my car now runs awesome, really quiet too, the only thing is it rocks back, not so much as it did before i changed the leaf springs, and i have no idea why it does this. even my dads friend who is a chevy guy said he has never heard a dodge start and run this good he could have been exaderating tho.
 
70Swinger said:
acctually im just in the planning stage lol, see wut kind of advice i get cuz im new to all this so i need al the help i can get, and i want to learn as much i can about it. So that maybe one day i could be the one giving advice for once ahah, i have a while yet. im gonig to need a new case thats for sure they dont sell any gear ratios on summit for a "741" case 8 3/4. I was orginally just going to go with the build up out of mopar muscle magazine but after i read more into it, it doesnt sound all that great. i want a 318 that i can race and be a street cruiser and survive.
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I´ve never seen anything steeper than 3.73 for a 741 case. It´s the weakest of the 8 3/4 units, not tough enough for racing, so nobody supports poor A-Body drivers... :sad2:
 
alfred340 said:
I´ve never seen anything steeper than 3.73 for a 741 case. It´s the weakest of the 8 3/4 units, not tough enough for racing, so nobody supports poor A-Body drivers... :sad2:
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really? i found a "741" case no posi with 3.91 gears in it. But yea i know its the weakest, its the only small pinion one, i want to find a "742", but it would be alot easyier to find a "489".
 
My 741 case has 4.10's from Richmond for the last 15 years.
Isn't there a way to instal 742 inside a 741 or something like that?
How much can you lighten up the car? Also, how much does it come in at now. This lightening program your after, hows the aftermarket for fiberglass parts?
 
i can get both bumpers, both valance panels, fenders, hood, deck lid. i think thats it. i have no idea about the building a 742 in a 741, if i found a 742 case would it fit where my 741 was?
 
Ya, all 8-3/4's will interchange in the housing.
Somewhere along the line there was a spline count change *I Think*
But would not worry about it.
 
Faulty ignition from plug to distrib.
Valves not closeing fully from debries or worn/broken valve spring or bent.
Poor fuel distirbution from dirty/worn carb.
The list could go on.
 
rumblefish360 said:
Faulty ignition from plug to distrib.
Valves not closeing fully from debries or worn/broken valve spring or bent.
Poor fuel distirbution from dirty/worn carb.
The list could go on.
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but having those wouldnt my car run rough? cuz my car runs liek a dream so quiet and smooth. i know my started has some worn teeth cuz the odd time that i go to start it, it grinds.
 
GotDart said:
Did you check for broken motor mounts?
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yes i did acctually, and they are fine. i have the motor mounts that have the bolt going right down the middle holding its all together, if that helps any ill try to describe it more if u need me too
 
70Swinger said:
these magnum heads are they wut alot of ppl refer to as swirl heads? and how big are the valves in this heads? and they will have better compression then the older 360 heads?

Thnx for the help guys i need as much as i can get.
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The magnum heads are 94 and later 318-360 heads. They have 1.92" intake and 1.62" exhaust valves, closed combistion chambers and 1.6 ratio rockers. They flow better then a stock X or J head and the closed chamber allows you to build for good quench wich will make the motor more efficient and have better torque and throttle response.

These are the heads from the Mopar Muscle article. They use KB pistons at zero deck and a .039" head gasket thickness to set quench distance. The heads were used with no porting, A comp Cams 280H cam and a M1 single plane intake. It made 400hp on Westechs dyno but is probably closer to 350-360hp in real life. I also think a Magnum RPM Air gap would be a better intake for this motor.
 
they also used a 273 forged crank, but that creates problems in automatic cars and thats wut my car is, so wut crank could i use? yea i was reading about the air gap manifold lastnight and i think thats the one im gunna go with
 
70 Swinger, we specialize in 'new-by's' Some good and knowledgable people on this board. I agree with Rumblefish on the heads..only thing I would ad is to have the valves back cut 30 degrees while you are at it. Any year J or U casting will work and install the 2.020 intake valves. Try to keep the compression around 10 to 1. Good luck there 70 Swinger and keep us posted. Terry.
 
:eek:fftheai:
70Swinger said:
any ideas wut would cause my engine to shake back and forth?
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How about timeing chain jumping a tooth? Sticky valve? Debrise not allowing it to close? Carb dirty? Crossed ignition wires? Broken tranny mount/rubber ripped/torn?

You claim it purs. Then you say it started to shake but still ran smooth.
It is hard to guess what the problem may be on line and I'm just offering a thought on it. OK, stabs in the dark. But it's dark were I'm at. (LOL :eek:fftheai:)
Check it anyway. Nothing to loose except a few min.'s time.

Also Adams suggestion on Magnum heads is very good if the X,J,U heads are not found. On a 3-8-teen, or any small block (In general) there likly to perform better due to the closed and reduced cc head chamber.
 
rumblefish360 said:
:Also Adams suggestion on Magnum heads is very good if the X,J,U heads are not found. On a 3-8-teen, or any small block (In general) there likly to perform better due to the closed and reduced cc head chamber.
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which will prefrom better the magnum heads or the X, J, U, heads? Where do megnum heads usually crack that way if i find a pair i can check,could jsut get magnum heads until i find X,J,U, heads, ill have to look around the wrecking yards here.
my carb is clean, my valve train does make some noise when its running, timming chain could be another possiblity ill have to check.
 
the magnums perform alot better, just take a look at shadydell's site for flow numbers. Plus is you buy the retro fit R/T heads from MP you can use your stock intake. R/T's flow stock what the best x,j head does ported.

Steve
 
R/T's flow stock what the best x,j head does ported.
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Only on the flow charts at sheadydell. Head flow varys alot from head to head. Ryan will tell you that. He'll also tell you the a X or J etc.. can be ported beyond his listed numbers. 270 cfm is possible without getting wacko. Of course this will depend on the actual head itself.
Also some R/T's tested at other places like Hughes for example flowed alot less than advertised.
If you can get a head cheap enuff, then it could be worth the dollors and sense over brand new heads. Of course this falls under all things pending. Where you want to be vs. money in pocket. What one is willing to spend vs. performance gained.
Dick Landy's shop had a demo on highly modified head that went over 300 cfm. However, in order to reach that level, I would call it above and beyond the call of duty and sanity to achieve.
Welding the port and moveing the port roof to the valve cover line with making a new roof with I think it was A-B puty or something like it...

Just do not ever race flow bench vs. flow bench.
The real deal is what you can get from a head on the same bench, same operater, same technique.
 
Rimblefish360, I agree with you on the flow benches, but also this has to be thought of, is the fact that the camshaft that is being used has to match the engine, along with the intake and exhaust, then also the valve size. Then whats the engine going to be used for, everyone wants big power but how many can really afford it. Little things go along way, the thing is which little things? Then which do the best for the engine used.
Also Rumblefish360 I've given it some very good thought about what we have talked about in past PMs, I'll sit down this week and come up with some ideas and sinerios as this is a off week so to speak on heads, I'll also put cams and compressions with it so it will work as stated. PM me if you like for your ideas, and we'll discuss them. I think that this would be very good for all.


BJR Racing
 
the fact that the camshaft that is being used has to match the engine, along with the intake and exhaust, then also the valve size. Then whats the engine going to be used for, everyone wants big power but how many can really afford it.
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This I know. Previous post was a in general thing. Not that I would do a Dick Landy mega mod on my heads or take my 318 and install a Comp cam 308D-R6 (Old base line 360 mech. S/S cam) and expect it to work. :wack:

I'll get back to you in a few days. My job is giving away money just for being there for the "Just incase." I'm sure to work many double shifts and a 24 hour run or two this week.
Gotta love winter for money. Get it while you can before it melts away. :thumblef:
 
i found a pair of magnum heads here, off of a 1994 318. I talked to the guy and he wants $300 canadian for the pair. Good price? do bran spanking new magnum heads bought form mopar performance, be better then rebuilt used magnum heads?
 
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