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  #1  
Old 05-28-2002, 11:02 AM
freak007 freak007 is offline
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Default cam/compression advise...

ok,I am building a 360 for my 4wd truck,I have narrowed my cam choices down to 2,but I need the advise of those who are more experianced in this area...


the 2 cams I have chosen are:

Comp 203/219,.442/.462 lift,110* lobe seperation,-9 overlap

Crane 204/216,.427/.454 lift,112* lobe seperation,-14 overlap



which of these cam will make the most power under 4500 RPMS

also how much compression can I run with these and still run cheap(87 octane) gas?
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  #2  
Old 05-28-2002, 02:01 PM
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rumblefish360 rumblefish360 is offline
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I would guess cam #2. It looks like it should build more cyl. pressure due to over lap being longer. Run it at 8.5-1. You should be good.
Remember, I said guess.
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Old 05-28-2002, 02:18 PM
451Mopar 451Mopar is offline
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These are pretty mild cams, I would shoot for 9.0:1 compression.
It is allot easier to lower the compression ratio, than to increase it.

Remember, before 1970 a stock 318 had an "advertised" 9.2:1 compression and a really mild cam (240/248 duration, 0.375"/0.399" lift) and this was a "regular" fuel engine.

Why not the Hughes HE0914AL cam? 208/214 @ 0.050", 0.458"/0.470" lift 112 LSA. Power range of this cam is idle to 4,200 RPM.
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Old 05-29-2002, 07:51 AM
freak007 freak007 is offline
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the reason I did not concider the hughes cam was for several reasons,#1 cost,#2,many of you know I use DD2000 to compare various engine combos,the 208/214 had less low end torque,and and dropped below 400 LBS@4500,I am after a torquey engine for me 4wd,the only other cam that compared to the crane or comp was the MP260/268,I would still concider this one,but I have heard MP has some QC problems...
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  #5  
Old 05-29-2002, 08:02 AM
freak007 freak007 is offline
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451Mopar-how do you figure it is easier to lower compression than it is to raise it?to raise it all I have to do is yank my heads and shave them some more...
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Old 05-29-2002, 01:18 PM
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rumblefish360 rumblefish360 is offline
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It's easy to lower it via a thicker head gasket or a shim from MoPar that's .060 thick.
When you combine the .060 shim and a .039 gasket, you can go preety far. Total = .099
Need to go lower? Use a .054 gasket from Fel-Pro. Total = .114
It's quick and easy this way. No machine shop time. Just extra head and intake gaskets to take up the room.
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Old 05-29-2002, 02:08 PM
451Mopar 451Mopar is offline
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What I mean about the compression ratio is unless you machine everything, your compression usually ends up lower than you would think it should because the stock engine blocks are usually taller than spec, and the heads usually are larger CC than spec.

One of the Mopar Magazines Documented a 360 engine with the 8.5:1 pistons as having an actual compression ratio below 8.0:1 (it was in the 7's if I remember correctly.)

Also, it is easier to change compression ratios with different thickness head gaskets, mainly because the gaskets bore size is larger than the cylinder heads chamber size.
Besides gaskets thickness, if you polish the combustion chambers you will increase the head volume further reducing the compression ratio.

Can you E-Mail me your Desktop Dyno data file? I have DD2000, and would like to see how it compares to what I have.
I did a quick comparison of the two cams, and Desktop Dyno showed almost identical power/torque with either cam.
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  #8  
Old 05-30-2002, 09:08 AM
freak007 freak007 is offline
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ok,I will attach each combo i tried...
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  #9  
Old 05-30-2002, 09:26 AM
freak007 freak007 is offline
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451 what is your e-mail addy??
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  #10  
Old 05-30-2002, 10:38 AM
451Mopar 451Mopar is offline
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My E-Mail is j.grosso@ix.netcom.com
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  #11  
Old 05-30-2002, 01:51 PM
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Post Raising /Lowering Compression

My .02 cents. When you're adding gasket thicknesses to open chamber heads you have to be careful because you don't want your quench clearances too high. If you go past about .050-.060" you lose a lot of your squish & quench which hurts efficiency and invites detonation. This is only with open chamber heads. Turbulence makes a lot of difference here and the closer your clearances the more turbulence you'll have. BTW, I think cam #1 will make more power below 4500 rpm because it WILL make more cylinder pressure at low rpm than cam #2. The less overlap and duration will cause it to trap more of your intake charge than cam #2. These 2 cams will perform close to the same but #1 will give you a bit more grunt at low rpm, cam #2 will run a bit faster at high rpm(4500-5000). Wedgehead
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  #12  
Old 05-30-2002, 06:45 PM
451Mopar 451Mopar is offline
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If you are building a low compression 360 with flat top or dished pistons, the engine won't have any effictive quench (or squish) no matter what head gasket thicknessyou use. This is mainly because the stock 360 heads (unmilled) usually are about 0.080+" from the head surface to the chamber surface, and the pistons will likely be way below the block deck, so even with a zero deck flat top and a 0.020" steel gasket that's 0.100+" quench distance with unmilled heads.

The new Keith Black #372 "D-Cup" piston with a 0.085" quench dome is about the only way you can get good quench on a low compression 360 engine using stock iron heads.

I used the older #232 (0.050) quench dome piston on my 360 and had to mill the heads and block to get the proper quench distance, but all the milling resulted in a 9.5:1 compression ratio, which is what I wanted anyhow
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Old 05-30-2002, 10:17 PM
451Mopar 451Mopar is offline
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freak007, I got the Dyno 2000 files.
The main difference(s) between my simulation files and yours is:
#1. Exhaust. You are selecting small tube headers with open exhaust, I selected small tube headers with mufflers.
#2. Heads. My head flow numbers are more conservitive than the ones you are using. I used real head flow numbers from the stock 360 heads, and added a small percent to that to account for the mild port work. Your selection of bowl ported heads would represent fairly good flowing / ported heads, expecially on the exhaust side.
#3. My simulation uses 9.5:1 compression, you use 9.0:1, but that is where my compression ended up being. I think the simulation only shows a small gain with the higher compression.
#4. I was going to use a Thermoquad, so my carb CFM was 780 cfm. Desktop dyno shows very little difference with the larger carb.
#5. I am runing 1.6:1 rocker arms so my valve lift is much more (0.489"/ 0.501" with the hughes 0914al cam. also the rocker ratio makes the cam "look" about 2-3 degrees larger @ 0.050" "at the valve".)

I will E-Mail you my Dyno 2000 file
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  #14  
Old 05-31-2002, 08:14 AM
freak007 freak007 is offline
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thanx for the help 451,I found your addy on your web site:P

1-when i build an exaust it loses <1% of its open pipe power

2-I am glad you have some "real"numbers,I couldn't find any

3-you say you run 9.5 compression,what feul does it use,what cam did you use,how do you like it?tell me everythingLOL

4-I did not use the TQ because I have always had trouble tuning a stock TQ,plus i can get a 650-700cfm holley for $250,less at the local swaps...

5-I am on a budjet,so unless i can get a GREAT deal on 1.6,or they make ALOT more torque,I will have to keep the 1.5s
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  #15  
Old 05-31-2002, 12:31 PM
451Mopar 451Mopar is offline
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The engine is on the engine stand. I was going to put it in a 1983 RamCharger 4x4 with 3.21:1 gears and 31" tires, that is why it was built for low end torque. I also live in the Denver, Colorado area (Mile High altitude) so running 9.5:1 compression at this altitude is not a problem, but I hope it would still run well on pump gas at lower altitude, but so far the engine has not been ran. The frame of the RamCharger was bent so I put the 318 back in it and sold it. The engine now will likely be put into my wifes 1969 Coronet 500. I have been thinking of having the engine dyno tested just to see what it actually does for power, but right now I don't have the money to do that.

The engine is a 360 bored 0.040" over (it wouldn't clean up at 0.030".) The crank was turned to clean it up also. Other block work was to align hone the main bearings, machine the deck surface to bring it into spec so the Keith black #232 pistons were 0.002" below the deck. The bore honing was done with Torque plates too. The rods were fitted with ARP rod bolts and resized. The rod ends were narrowed (required with the KB #232 pistons.)
The rods, pistons, and crank were ballanced with a new dampner and the special 360 B&M Flexplate.
The oiling system uses a Melling High Volume pump, factory type windage tray and factory truck oil pan and pickup (soon to be replaced with a car pan/pickup so the engine will fit in the Coronet.) A new Mopar oil pump drive, I also used ARP main studs on the main bearing caps, except under the oil pump.
The heads are just the 360 heads from AeroHead with 2.02"/1.60" valves that I ported at home. Because the KB#232 pistons are a "Quench" design with a 0.050" quench pad, I had to mill the heads about 0.040+" to get the correct quench distance of about 0.000" with out a head gasket. I'm using the fel-pro head gaskets that ae about 0.040", do that sets up my quench distance. I also used ARP head studs (more overkill parts on this engine.)
My intake is the Edelbrock Performer with EGR, and the Thermoquad carb mainly because I wanted to see if it would pass emissions in the 1983 RamCharger.
The cam is the Hughes HE0914AL, with the hughes lifters, springs and retainers. I found out the AeroHead retainers will not work with the Hughes valve springs.
The rockers are the Crane gold 1.6:1 aluminum roller tip rockers, with the recommended crane pushrods. I found that I had to slightly shim the rocker shafts to gewt the correct geometry with this setup. I used the Mopar billit aluminum rocker shaft hold downs on the rocker shafts (more overkill.)
The timming chain is just a Cloyes double roller, a Mopar moly coated fuel pump eccentric, Carter High Volume fuel pump, and the Mopar High Volume water pump finish off the front of the engine. I bought some Dynomax truck headers for this, but since the truck is gone I'll sell them to you if you need some.
I also bought two of the large case Dynomax "Hemi" super turbo mufflers (quieter than the redular turbo mufflers), and since I was looking for good emmissions, I bought two Dynomax "Super Converters", 3-way Catlatic converters with Air tube.)
The ignition is just the Old Mopar Electronic conversion setup with the small chrome Jacobs coil and Jacobs plug wires.

Price wise, this was a fairly expensive engine because all the stock bolts were replaced with ARP fastners. I did not re-use hardly any orifinal parts on the engine. The block, rods, and crank are about the only remaining original parts.
Some things that added to the cost that may not be needed are the fore mentioned ARP bolts/studs (except the rod bolts should be used), the Catalatic (sp) converters, the EGR version of the intake, The Mopar Rocker hold downs, water pump, fuel pump eccentric. That would save over $500 on the buildup right there.
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  #16  
Old 06-02-2002, 09:50 AM
freak007 freak007 is offline
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hmm...sounds like a solid buildup,but DD says the file you sent is invalid,do you want to try again please??


I am currenty working on getting a 360 to replace the 318 that is currently in there,but I am still interested in your headers,what do you want for them?how much would shipping be to zip code 55744?


another question:the transmision recently startyed leaking/slipping,my 2wd has a rebuilt 727 with 2000 miles on it,can I unbolt the tailshaft an put the t-case on there to put it in my 4 wd??
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  #17  
Old 06-04-2002, 09:45 AM
freak007 freak007 is offline
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'ello??
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