Moparts
basic360 buildup
Posted By: volaredon
basic360 buildup - 01/11/15 02:46 AM
This engine is going into my son's 89 Ramcharger when done, the truck's TBI is going into the garbage with the computer, truck will have a carb (probably one of the 2, DemonSizzler prepped TQ's I have in the attic)
3 season driver, tow vehicle, best MPG I can get "for what it is" (a 4WD "brick")
I have a '76 360 in the machine shop now. (I tried talking the kid into a carb'd magnum 360 but he bought this motor 1st)
Looking at basically a stock 0.030" overbore rebuild on the short block. Crank fine, polished up "STD". "clean up" cut on the deck if needed.
I'm putting brand new EQ Magnum heads onto this LA block. already have the heads. stock-for Magnum sized valves (not 2.02's) Bought the 318-B (LA bolt pattern) heads direct from EQ, got the fully assembled ones.
Cam; I am looking at a COMP 260H with their nitride treatment.
Pistons will be Perfect Circle, Badger etc stock replacement style.
Intake; Edebrock, not sure if we will go with a "standard" performer or an RPM... I don't remember which one of these will allow use of the factory A/C (alum. compressor)
Not wanting to replace torque converter (trans is fresh as is converter
Will break in on manifolds, but will get headers shortly after.
sound like a pretty decently matched system? I have built a few motors over the years, most pretty much "stock"
this is my son's 1st engine build I am helping him through it and showing him some of the "tricks" I have learned since then, while we are at it w/o some of the past mistakes that I have made.
I have done 1 other mag head swap/ that, on a 83 318 in a 3/4 ton pickup, that one got a stock 360-2 cam put into it at that time,(same specs as a COMP 252 at 1/2 the price) on an unrebuilt 120K mile short block, and that combo really woke that engine up to a point of some people thinking I was lying about it being "only" a 318.
A COMP 260 has a lift of 0.440" I/E with stock 1.5 rockers and .460-something with the magnum 1.6s. I want increased torque and HP but do not want to worry about piston to valve interference.
Is there a similar spec'd cam (can be a different brand) to the 260H that will accomplish what we are after?
Posted By: aspenrt360
Re: basic360 buildup - 01/11/15 03:11 AM
I did a build very much like that with some parts I had kicking around. I ran a comp 270h it runs very well good power good economy too just make sure you check valve retainer to guide clearance. I had to trim mine a bit, no big expense but if you are to tight you will be sorry. have fun it will work nice
Posted By: volaredon
Re: basic360 buildup - 01/11/15 03:38 AM
you used Magnum heads? I'll have to look into the 270H vs the 260H.
I want as LITTLE interference issues as possible valve to piston, retainer to guide etc while still waking this motor up a bit from stock. I don't see this motor ever seeing 4500 on the tach, being in a truck.
Posted By: meus31
Re: basic360 buildup - 01/11/15 04:12 AM
Put a better piston in it to get 9.5 to 1 or so a stock 360 piston .080 thou down doesnt help gas milage or power.
Posted By: meus31
Re: basic360 buildup - 01/11/15 04:22 AM
My opinion is the comp xe250h would make the same power with better milage.
When I tested cams in an rv 360, I decided a Comp Cams 268AH-10 was about as ideal a cam as you could get for a low compression 360. Very nice low RPM torque and horsepower.
You can look up the article on Mopar Muscle websites tech articles.
Budget 360 camshaft testing.
Keith
Posted By: volaredon
Re: basic360 buildup - 01/11/15 05:43 AM
thanks for the replies guys keep em coming. How much CR am I looking to pick up with the Magnum heads, vs the stock 76 pass car 360-2bbl heads that I took off this motor? (all else being equal-- assume stock piston for now) I would love to get this motor to ~9-1/4 to 9-1/2:1 CR but not much more, I want it to still run on 87. If I were driving it I might be more willing to have to run 91; but with it being my son's truck, and with premium still being half a buck more a gallon (some stations even more) than 87, I don't want a motor that "has to" have the expensive stuff.
I will look into that cam for its specs as compared to what I was gonna run. I'm "NOT" saying I have to run a COMP brand cam, either.
Posted By: volaredon
Re: basic360 buildup - 01/14/15 04:51 AM
trying to bring back from about 5 pages buried;
On pistons; was looking at just stock type Badger or Silvolite.
but after suggestion above, I am thinking 9:1 flat tops with valve reliefs; that's 9:1 with stock smog heads I am thinking, with the Magnum heads (smaller chambers than the smog '76 era heads)I am thinking that it may be a a bit much for pump 87; do you guys agree?
and the machinist is telling me that if I go with anything "but" stock type replacements I'm gonna have the added expense of a balance job; It's the kid's 1st build and he's already wanting to go overboard, with me trying to tell him "hang on a a minute"
I want to teach him what I can about engine rebuilding on this one,
I want to build it up a bit while we are at it, but this is meant for daily driver duty in all but road salt season... so I don't want to overdo it. If I was building this motor for my volare I might do things a bit different than I am building it to go into a Ramcharger.
Check into the SpeedPro hyperutectic pistons. I'm not 100 % positive but I believe the weight is similar to stock
They have decent valve reliefs and no special ring gap needed like KB hypers.
The. Cost is right on them also.
Keith
Posted By: urdustd
Re: basic360 buildup - 01/14/15 07:03 AM
There are two hyper pistons Speed Pro (Federal Mogul) makes. P/n 405p which has a compression height of 1.576 with a 0.070" recess and typically yields 8:1 or so compression and H116CP which has a compression height of 1.66 with 5cc valve reliefs. It will give 9.5 to 10:1 depending on head volume. This is the one I used. I have 10:1 compression and run 91 octane but can run 87 without too much issue. My engine made 397hp/435ft lbs with a mild hydraulic cam and Edelbrock heads. I didn't have to balance mine with this piston.
With factory heads it might require better fuel. Good luck with what you decide.
Posted By: aspenrt360
Re: basic360 buildup - 01/14/15 10:29 PM
just got a set of the 116 cp pistons in yesterday really good bang for the buck. not an al out race piston by any means but a good economy piston that puts compression into a 360, the main thing they are missing. I just weigh one they are so close to the stock piston weight you can just go ahead and run them.
Posted By: aspenrt360
Re: basic360 buildup - 01/14/15 10:32 PM
I got the set of pistons, pins, and clips for about $270. can't beat that price for the whole deal! they were at summit
Posted By: volaredon
Re: basic360 buildup - 01/15/15 01:32 AM
Quote:
just got a set of the 116 cp pistons in yesterday really good bang for the buck. not an al out race piston by any means but a good economy piston that puts compression into a 360, the main thing they are missing. I just weigh one they are so close to the stock piston weight you can just go ahead and run them.
thanks for the replies guys.
So what CR would the 116s have with EQ's "Magnum" heads? (62 or 63cc chambers) We will go with either Victor or Fel Pro "stock Replacement" Magnum engine head gaskets.
One other concept that has been getting alot of press all over is "quench" I guess more quench means more CR before better fuel is needed to prevent detonation. but I don't quite "get" how you get the quench and exactly what it is.
Posted By: volaredon
Re: basic360 buildup - 01/15/15 01:35 AM
also (I think it was them) Perfect Circle used to make a cast flat top (no dish) for a 360. I am wanting to see if they still do.
Why are 360's all equipped with dished pistons where 318s aren't? They handicapped the 360 right from the factory, I wouldnt understand why theyd want that either. (though I know most 318s are "in the hole" a bit too)
Posted By: cudadoug
Re: basic360 buildup - 01/15/15 06:50 PM
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just got a set of the 116 cp pistons in yesterday really good bang for the buck. not an al out race piston by any means but a good economy piston that puts compression into a 360, the main thing they are missing. I just weigh one they are so close to the stock piston weight you can just go ahead and run them.
thanks for the replies guys.
So what CR would the 116s have with EQ's "Magnum" heads? (62 or 63cc chambers) We will go with either Victor or Fel Pro "stock Replacement" Magnum engine head gaskets.
One other concept that has been getting alot of press all over is "quench" I guess more quench means more CR before better fuel is needed to prevent detonation. but I don't quite "get" how you get the quench and exactly what it is.
Depends on your deck height. That piston at "0" deck, with a .041 gasket and 63cc chamber calculates to 10.7:1
.050 in hole, calculates to 9.5:1
Posted By: cudadoug
Re: basic360 buildup - 01/15/15 06:57 PM
Quote:
also (I think it was them) Perfect Circle used to make a cast flat top (no dish) for a 360. I am wanting to see if they still do.
Why are 360's all equipped with dished pistons where 318s aren't? They handicapped the 360 right from the factory, I wouldnt understand why theyd want that either. (though I know most 318s are "in the hole" a bit too)
Yes, you can still get replacement, dished pistons for the 360 through any auto parts house.
Here's another option that's C H E A P. They're an ugly pistons but have proven to be rock solid relaibale in a build such as yours. I even know of one set in a motor that's gone high 11's now for going 4 years. I know of another set in a pulling truck AND had 40K+ street miles on it. Motor came down last year for a freshen...pistons/rings were A-Okay!
http://www.summitracing.com/parts/slp-h405cp30/overview/make/chrysler
Posted By: aspenrt360
Re: basic360 buildup - 01/15/15 09:18 PM
I put a set of those 405's in a truck motor they work well too. a bit less comp though depends on what you want to build. and if you want to do some bolt on upgrades down the road.
Posted By: volaredon
Re: basic360 buildup - 01/16/15 02:08 AM
Quote:
Quote:
also (I think it was them) Perfect Circle used to make a cast flat top (no dish) for a 360. I am wanting to see if they still do.
Why are 360's all equipped with dished pistons where 318s aren't? They handicapped the 360 right from the factory, I wouldnt understand why theyd want that either. (though I know most 318s are "in the hole" a bit too)
Yes, you can still get replacement, dished pistons for the 360 through any auto parts house.
Here's another option that's C H E A P. They're an ugly pistons but have proven to be rock solid relaibale in a build such as yours. I even know of one set in a motor that's gone high 11's now for going 4 years. I know of another set in a pulling truck AND had 40K+ street miles on it. Motor came down last year for a freshen...pistons/rings were A-Okay!
http://www.summitracing.com/parts/slp-h405cp30/overview/make/chrysler
Yeah I know OEM style stock "dished" pistons are available everywhere "a dime a dozen", in the post where I asked that I was looking for a cast flat top (NOT dished)
Those ones you link to at summit are the ones I am looking into getting. Would I need a balance job to go with them vs the stock typed dished POS'?
Already have the Magnum heads on hand they are a definite to go onto this engine, looking for around 9:1 to 9-1/4 to 1 probably at most.
Definitely wanting a boost from the OEM sub-8:1
NOT wanting "cheap" for the sake of cheap nor bragging rights for "most expensive" 360 towing/4X4 motor but bottom line is BANG FOR THE BUCK...
Block at machine shop it has not yet bored as of 2 days ago/ was told to hold off on buying to be sure it'll clean up there; I wanted only 0.020 over but machinists claim 0.020 "harder to find" and pretty much insist on going 030 if any at all... so I have been shopping 30-over
Posted By: D-50
Re: basic360 buildup - 01/16/15 02:45 AM
I am pretty sure the 380 hp 360 magnum crate motor is 9-9.5 comp. I do not know what brand they are but you could look into that.
Posted By: volaredon
Re: basic360 buildup - 01/16/15 03:56 AM
Quote:
I am pretty sure the 380 hp 360 magnum crate motor is 9-9.5 comp. I do not know what brand they are but you could look into that.
that's exactly where I'd like this motor to wind up when all is said and done. no more though due to not wanting to be stuck running Premium.
Posted By: D-50
Re: basic360 buildup - 01/16/15 04:22 AM
I raced my 380 hp crate motor on 87 octane and ran a best of 7.27 @ 95 at 2950 lbs.
Posted By: cudadoug
Re: basic360 buildup - 01/16/15 04:23 AM
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also (I think it was them) Perfect Circle used to make a cast flat top (no dish) for a 360. I am wanting to see if they still do.
Why are 360's all equipped with dished pistons where 318s aren't? They handicapped the 360 right from the factory, I wouldnt understand why theyd want that either. (though I know most 318s are "in the hole" a bit too)
Yes, you can still get replacement, dished pistons for the 360 through any auto parts house.
Here's another option that's C H E A P. They're an ugly pistons but have proven to be rock solid relaibale in a build such as yours. I even know of one set in a motor that's gone high 11's now for going 4 years. I know of another set in a pulling truck AND had 40K+ street miles on it. Motor came down last year for a freshen...pistons/rings were A-Okay!
http://www.summitracing.com/parts/slp-h405cp30/overview/make/chrysler
Yeah I know OEM style stock "dished" pistons are available everywhere "a dime a dozen", in the post where I asked that I was looking for a cast flat top (NOT dished)
Those ones you link to at summit are the ones I am looking into getting. Would I need a balance job to go with them vs the stock typed dished POS'?
Already have the Magnum heads on hand they are a definite to go onto this engine, looking for around 9:1 to 9-1/4 to 1 probably at most.
Definitely wanting a boost from the OEM sub-8:1
NOT wanting "cheap" for the sake of cheap nor bragging rights for "most expensive" 360 towing/4X4 motor but bottom line is BANG FOR THE BUCK...
Block at machine shop it has not yet bored as of 2 days ago/ was told to hold off on buying to be sure it'll clean up there; I wanted only 0.020 over but machinists claim 0.020 "harder to find" and pretty much insist on going 030 if any at all... so I have been shopping 30-over
You'd have to compare published weights to know. But I would have it balanced regardless, as our forefathers at Mopar sometimes balanced on a "close enough" procedure. Balancing is always a good investment, IMHO.
Posted By: aspenrt360
Re: basic360 buildup - 01/17/15 07:10 PM
so I went to the weapons shop at work and weighed a stock bore 360 oe piston and a speed pro h 116 cp that is 30 over and they are really close less than a gram difference. the pin is close too. I am going to use some arp bolts on rebuilt stock 360 rods and run it. I think if you are not buzzing the crap out of it you would be fine. for sure it is always better to balance but they are so close.
Posted By: volaredon
Re: basic360 buildup - 01/17/15 09:08 PM
Quote:
so I went to the weapons shop at work and weighed a stock bore 360 oe piston and a speed pro h 116 cp that is 30 over and they are really close less than a gram difference. the pin is close too. I am going to use some arp bolts on rebuilt stock 360 rods and run it. I think if you are not buzzing the crap out of it you would be fine. for sure it is always better to balance but they are so close.
thanks that helps a bunch.
I m thinking hard about the 405CP's....
Posted By: volaredon
Re: basic360 buildup - 01/20/15 05:44 AM
ok; according to Summit the H 405 CP in 0.030 over lists at 584 grams. According to a '78, an 83 and an 87 FSM, the 360 pistons are advertised at exactly the same. Maybe I will not need a balance?
this motor will probably never see the high side of 4K RPM....
Posted By: volaredon
Re: basic360 buildup - 01/24/15 04:49 PM
OK; got the 405CP's. Also got the block and crank back from machine work yesterday. WOW has machine work gone UP Yikes.
For $438 I used to be able to get block, crank, AND HEADS done at the machine shop... we bought new heads so the machine shop didn't have to do any head work, and I am putting the cam bearings in myself this time even,,, I wasnt expecting them to charge me to remove the old ones, as I thought the "hot tank" operation would essentially dissolve them!
Granted, I don't put brand new heads on every build/ but with scouring Ebay for all the new parts (everything so far comingincheaper than Jegs/Summit but the same brands of parts I'd be gettin from them) it looks like we'll be into this build for around $2k, maybe a bit more by the time I get my 4 bbl intake (have a couple of carbs here to choose from already) and the cam, lifters and Tchain; I am spending the extra money to have the cam nitrided before it leaves the COMP factory, to help fight today's low zinc oil....
Posted By: volaredon
EQ head questions - 01/24/15 04:56 PM
Adding up the lift of a COMP 260H cam (.440") only with the Magnum heads' 1.6 rocker ratio that .440 lift, becomes .467;
Does anyone here see where I would have issues at that level of valve lift with valvespring retainer bind? Would I need to shave the valve spring towers on the heads
also what are the springs that come with the "assembled" EQ 318-B heads? I got these right from EQ via atheir Ebay site, not from Hughes or a Cleawater Cylinder Head type place.
Posted By: cudadoug
Re: EQ head questions - 01/26/15 11:40 PM
Quote:
Adding up the lift of a COMP 260H cam (.440") only with the Magnum heads' 1.6 rocker ratio that .440 lift, becomes .467;
Does anyone here see where I would have issues at that level of valve lift with valvespring retainer bind? Would I need to shave the valve spring towers on the heads
also what are the springs that come with the "assembled" EQ 318-B heads? I got these right from EQ via atheir Ebay site, not from Hughes or a Cleawater Cylinder Head type place.
Retainer to guide clearance on the magnum heads is usually good to .520 lift.
Posted By: dogdays
Re: EQ head questions - 01/27/15 12:31 AM
For the minimal amount of time and effort, not to mention money, that it costs to cut down the guides, I'd say do it and forget it.
On my 302 heads I used a $40 or so cutter with the proper pilot size and kept the stock OD of the guides at 0.625 so I could use the stock seals. It took me less than 15 minutes from beginning to end. I was surprised at how easy it was.
One piece of advice, don't drop the cutter down onto the guide, I chipped a carbide tooth doing that. So, I had to do a little extra cleanup.
R.
Posted By: GO_Fish
Re: EQ head questions - 01/27/15 06:53 AM
Don,
Late to the conversation here. I installed Mag heads on my low mileage '74 360 LA short block (from a van). Dished stock pistons, about .10" (!?!) in the hole. Shaved my Mag heads .020" and got the calculated compression up to 9:1 with the dished pistons. No knocks on 87 octane, has run a best 13.59 in my A body barracuda (no pro tune, I'm sure it has more left). If you installed flat tops without shaving your Mag heads, I'd guess you'd also be in the 9 to 9.5:1 range, which should work well with pump gas and Mag heads. Make sure to get an accurate weight on the truck, and match your cam and torque converter for best results right from the start.