Tearing down the 318..suggestion

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qwk dust

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Well, Our plan for the little teen has been changing a little. Our plan was a very hot little street car with mostly strip set up. As time has passed we are trying to conserve money and depending on what we find when we pull the motor we may not be doing a full rebuild with the KB 167s etc for the time being. We had planned on the KB167 flat top pistons bored .030 over, 302 casting heads milled a little, pocket ported and gasket matched to both the header and 360 intake gaskets, an RPM air gap intake, street avenger 670 carb and a fairly large cam like maybe an XE274H or the like and Hooker headers with 2 1/2 dual exhaust. We have 3.90 gears and had not decided on a torque converter stall but did plan to add a higher stall TC to deal with a fairly big cam for a teen. A small 100hp N20 shot was also planned

We had not decided on the extent of the head work and I was going to try to do some of it myself. I really thought I wanted 1.88 1.60 valves although some of the comments and advise I have read of BJR suggests maybe keeping the 1.78 1.50s. I would spend some money on the heads and it may even be in the cards to get them up to Bobby if I could since he is not too far away.

Anyway, as the collection of parts has proceeded I got a new 670 street avenger in the box for $150, a new RPM Air Gap for $170 shipped and a new Comp Cams 268H cam kit for $200 shipped. (gotta love Craigslist). The cam is smaller than what we had planned but the deal was too good to pass up.

Questions: 1) Am I going to be unhappy with the cam? 2) given the gears and cam can I just use the stock torque converter for the time being? 3) What do you think about needing more head work? and 4)..generically, what would the best way to get the compression up some without taking the whole motor apart (if she checks out good with the stock pistions)..mill the heads a little or just go with a thin head gasket and wait until the full rebuild is in the cards?

We really wanted to build this little teen up to be close to 400hp but as it goes along it looks like maybe 325 give or take is where we are heading. Thanks and sorry for the long post
 
Darn. No thoughts or suggestions. I know the teen isn't the most popular build but for the time being we just thought it would be fun. Are we going in the wrong direction with the set up as it has morphed into?
 
Questions: 1) Am I going to be unhappy with the cam? 2) given the gears and cam can I just use the stock torque converter for the time being? 3) What do you think about needing more head work? and 4)..generically, what would the best way to get the compression up some without taking the whole motor apart (if she checks out good with the stock pistions)..mill the heads a little or just go with a thin head gasket and wait until the full rebuild is in the cards?

We really wanted to build this little teen up to be close to 400hp but as it goes along it looks like maybe 325 give or take is where we are heading. Thanks and sorry for the long post

A long post is hard for me to read though. This is my thrid time on it. My eyes can't handle long posts or threads. I gotta break'em down.

But, to comment on it...........

I'm not sure on the cam. Your happiness is an unknown to me so, making a change from the larger one to a smaller on, the question is. will you be happy with a downward bracket power band from the one listed above it?

You can use the stock conveter with decent results with the 268 cam. With the larger cam, it will lag a bit for best results.

Consult BJR on the amount of head needed.

On compresion, I'd wait for new pistons rather than mill the head. The lower ratio will still work OK with the 268 cam. Not so super with the larger XE.

If you build it the second way listed, you can still enjoy it with the bolt on parts and cam while amassing money for the proper bottom end build.
 
I think your cam will work fine with the 3.90 gears,
I kept the stock 2.93 gears for my 318 build.

I used #302 heads, stock valve size, stock pistons, and LD4B intake;
2.25" duals and stock exhaust manifolds.

Your cam should work nice with 3.50 to 3.90 gears. :)

Brand: COMP Cams
Product Line: COMP Cams High Energy Cam and Lifter Kits
Part Type: Camshaft and Lifter Kits
Part Number: CCA-CL20-212-2
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,500-5,500
Intake Duration at 050 inch Lift: 218
Exhaust Duration at 050 inch Lift: 218
Duration at 050 inch Lift: 218 int./218 exh.
Advertised Intake Duration: 268
Advertised Exhaust Duration: 268
Advertised Duration: 268 int./268 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.454 in.
Valve Lift with Factory Rocker Arm Ratio: 0.454 int./0.454 exh. lift
Lobe Separation (degrees): 110
Intake Valve Lash: 0.000 in.
Exhaust Valve Lash: 0.000 in.
Grind Number: CRS 268H-10



The cam I used.

Brand: Mopar Performance
Product Line: Mopar Performance Purple Camshaft Kits
Part Type: Camshaft and Lifter Kits
Part Number: DCC-4452759
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,200-5,200
Intake Duration at 050 inch Lift: 221
Exhaust Duration at 050 inch Lift: 228
Duration at 050 inch Lift: 221 int./228 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 268
Advertised Duration: 260 int./268 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.430 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.450 in.
Valve Lift with Factory Rocker Arm Ratio: 0.430 int./0.450 exh. lift
Lobe Separation (degrees): 110
 
Thanks for the thoughts folks.

Rumblefish...you are right....too long of a post. I have noticed long posts many time get less response. Sorry about making your eyes bleed..8).

Cavemanmoron, have you ever taken your set up out to the track? How does the cam sound? thanks again
 
No problem QD. The comp cam is a mello grind by compare to the Mopar graind. Ramp rate is also mello. It'll make good power, but that MP grind should really make it crisp.
 
No track time, but I can tell I have a lot more torque,
that I had with the stock cam.




Thanks for the thoughts folks.

Rumblefish...you are right....too long of a post. I have noticed long posts many time get less response. Sorry about making your eyes bleed..8).

Cavemanmoron, have you ever taken your set up out to the track? How does the cam sound? thanks again

You can listen here at Youtube./

http://www.youtube.com/watch?v=Ud8mci4rjFU
 
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