360 engine build opinions - first engine build

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plymouthy

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My daughter and I are building her first engine; a 360 to install in our basically stock 73 duster (8-1/4 rear end). Our plans are to install it with a Mopar OD automatic Tranny. This will be a daily driver (dependable), with the occasional trip to the strip(performance). We want to build something with a HS student budget and a nice idle lope and fuel efficiency. So far we have a good solid engine ready to go to the machine shop. I would like suggestions on cams, pistons, rebuild kits, carb, manifold, heads, torque converter... Any help would be appreciated, I'll post pictures when we're done.
 
My daughter and I are building her first engine; a 360 to install in our basically stock 73 duster (8-1/4 rear end). Our plans are to install it with a Mopar OD automatic Tranny. This will be a daily driver (dependable), with the occasional trip to the strip(performance). We want to build something with a HS student budget and a nice idle lope and fuel efficiency. So far we have a good solid engine ready to go to the machine shop. I would like suggestions on cams, pistons, rebuild kits, carb, manifold, heads, torque converter... Any help would be appreciated, I'll post pictures when we're done.


Welcome!

Goggle up CamQuest from Comp Cams. It's a download you can use to see what various build options will net your horsepower and torque. You will need to know what compression,valve size,carb,vehicle weight,and intake. Then you can check different cams my Comp Cams to see what the motor will produce.
 
Economical builds would reuse as much stuff as possible.

Bore the engine .030 and use honing plates. KB 107 pistons will get the comp up. Shoot for around 9.5:1. Stay under .230 duration for driveability's sake. Pocket port and gasket match the heads. Upgrade the intake valves to 2.02. Backcut the exhaust valves.

Shop around for parts. Look at places like Summit, PAW.
 
Good, congrads!


We want to build something with a HS student budget and a nice idle lope and fuel efficiency.
OK, this is good. Budget known. Is your 360 a complete engine?
What parts are missing from the engine?

On a cam, you'll need to help here a little bit on the driving RPM range of the car. OR, a gear ratio and tire size would help. Once I know this, I'll recomend a cam.

I would like suggestions on cams, pistons, rebuild kits, carb, manifold, heads, torque converter...

On rebuild kits, click here; http://www.summitracing.com/ and then call them up direct. They will be happy to sub out parts for others in there kits. Like pistons and cam.

The intake and carb can varry alot. Your heads, the stock OE castings, are all you'll need. I would not go to a 2.02 valve. Just back cut what is there.

If your a little bit of a do it yourselfer, a parts washer and bench top blast cabinet are very nice additions to a home shop. So is a wire/grinding wheel.
 
My daughter and I are building her first engine; a 360 to install in our basically stock 73 duster (8-1/4 rear end). Our plans are to install it with a Mopar OD automatic Tranny. This will be a daily driver (dependable), with the occasional trip to the strip(performance). We want to build something with a HS student budget and a nice idle lope and fuel efficiency. So far we have a good solid engine ready to go to the machine shop. I would like suggestions on cams, pistons, rebuild kits, carb, manifold, heads, torque converter... Any help would be appreciated, I'll post pictures when we're done.

Please check out the great Mopar Supercharged 360 Small Block I have 4-Sale at the following:

http://www.forabodiesonly.com/mopar/showthread.php?t=32860
 
Good, congrads!


OK, this is good. Budget known. Is your 360 a complete engine?
What parts are missing from the engine?

Yes the engine is complete and I have a tired 318 in the car now with a 4bbl stock manifold.

On a cam, you'll need to help here a little bit on the driving RPM range of the car. OR, a gear ratio and tire size would help. Once I know this, I'll recomend a cam.
gear ratio I think is 3.23 open, tires are 15" cragars with 235 70 basic tires


On rebuild kits, click here; http://www.summitracing.com/ and then call them up direct. They will be happy to sub out parts for others in there kits. Like pistons and cam.

The intake and carb can varry alot. Your heads, the stock OE castings, are all you'll need. I would not go to a 2.02 valve. Just back cut what is there.

If your a little bit of a do it yourselfer, a parts washer and bench top blast cabinet are very nice additions to a home shop. So is a wire/grinding wheel.
I have all this in my little two car garage, just need to make more room to get the car in:profilel:
 
Kb107's, Comp XE268H, Performer RPM/LD340/Air Gap, 750 vac sec holley, good valve job with pocket porting, headers.

Be a sound strong running engine with about 350hp and 390-400lb tq.

Here's that combo with 2.5" exhaust & dynomax mufflers IIRC
http://s16.photobucket.com/albums/b50/opkyle/?action=view&current=DemonontheRoad009.flv

I like that cam.
I thnik you may be a little low on the est h.p though.

Could see 400 h.p at the flywheel with that combo.Probably more torque too.

Hey Rumblefish. Why not a 2.02? Motor could use it imho. Just curiouse!
 
Needsaresto, Thats a dyno combo I believe they made just under 400ftlbs with it.

And Rob. Those are flowmasters not dynomax
 
Thanks Adam. Forgot which mufflers Kyle got. He was talking all sort of mufflers at the time.

The engine made 347hp and 395 tq on a dyno. Heads are the bottleneck. These were 587 casting with some bowl/runner clean up. I think it had some more HP available in the tune, but, didn't have time to mess with it. It's a good 1hp per C.I. combination. I think we are going to hook up an LM1 and RPM converter to the car to get the carb dialed in.

With a bigger camshaft, 400hp isn't out of the question. This engine needed to be a nice street piece and work with a max 2500 converter and 3.23-3.55 gears.
 
Hey Rumblefish. Why not a 2.02? Motor could use it imho. Just curiouse!

Doesn't need it with a small cam in a heavy (ish) car. A smaller valve will increase or keep the velocity up and fuel in a finer misty state for a better burn. (Even better with a quenched area) The OE poster said mileage.

A 2.02 will drop low end torque and not allow fuel to break up as much making a efficent burn less likely there by dropping mileage. The top end power difference will be small and the low end torqe advantage of a smaller cam will be given away.

This leeds to a softer/slower bottom end where street driving and mileage can go down the most. While at cruise, the RPM will still be low. The 2.02 will not come into play until later up in the RPM band.

Now, If I were doing this in a track only car, or without care for mileage, sure, a 2.02 would be employed and the heads would get ported out, which he will not need, and the list of changes would go on.
 
Now that I think about it, a nice stop light bandit would be somthing like this for my Duster;

4.30 gears, 3000 stall, 1-3/4 super comps, 2,02 heads milled for a quench area on a zero deck pistoned 360. Well ported. Thick T-Q gasket on top of the modded LD-340 for the 850 cfm carb or RPM and a 750AFB / 800AVS, S/S springs. As wide as they get rear tires. For a cam, I'm looking into doing a roller. Preety much from here on out, thats all I want to look at. No break in time and a crazy ramp and duration @ .050 is a norm by compare to a Hyd. or most solids.

Nice stop light bandit. Not what he asked for.

The Crane you see me list alot is what I have in my teen now and is capleable with the right gear and stall to runs 12's in a 360.
Mikel (SP) Beck has done it for awhile now. He also runs a OD tranny for traveling/street duty if need be.

That Crane I have run before in a teen w/a 4spd. I still was able to get 18 MPG's out of it and run 13's. (high)
 
I'm planning a build with similar objectives, here's what the plan is so far:

- mildly ported Magnum heads
- Hughes HEH2328AL or HEH1928AL cam, still haven't decided yet
- TTI headers
- Edelbrock RPM Air-Gap intake
- KB hypereutectic pistons, sized for ~10.5:1 compression
- Edelbrock Thunder AVS 650 cfm carb

I know 10.5:1 compression is rather high for an iron-headed pump-gas engine, but with some combustion chamber mods (edge-radiusing) I should get phenomenal combustion speed and detonation resistance, allowing me to run less timing advance and lower-octane gas (hopefully as low as 87-octane!!!). All these things, along with an OD 4-speed manual should hopefully get me at least in the mid-20's highway gas mileage.
 
I'm planning a build with similar objectives, here's what the plan is so far:

- mildly ported Magnum heads
- Hughes HEH2328AL or HEH1928AL cam, still haven't decided yet
- TTI headers
- Edelbrock RPM Air-Gap intake
- KB hypereutectic pistons, sized for ~10.5:1 compression
- Edelbrock Thunder AVS 650 cfm carb

I know 10.5:1 compression is rather high for an iron-headed pump-gas engine, but with some combustion chamber mods (edge-radiusing) I should get phenomenal combustion speed and detonation resistance, allowing me to run less timing advance and lower-octane gas (hopefully as low as 87-octane!!!). All these things, along with an OD 4-speed manual should hopefully get me at least in the mid-20's highway gas mileage.

What areas of the combustion chamber gets edge radiusing? What do you use to radius the edges?
 
Pretty much all of them, but mostly the edges touching the quench areas. I'm still not sure of what to use to radius them yet, I have to ask the guy that "invented" it on another forum.
 
The idea is to smooth out any ruff edges or sharp edges to prevent hot spots that my casue pre-ignition.

You'll also might want to look into thermo coatings on the piston tops (Crown) and cylinder head chamber.

P.S. I'd go for the bigger cam myself and use a slightly thicker gasket. Just don't loose the quench effect. It is important in this type of set up.
If, IMO, you use the thermo coatings on the piston and cyl. head chamber, you might, MIGHT very well get away with 87. Otherwise, you'll need 89. And have the timing set to where you want it.

Do not retard timing to suite octane goals. This is a big power robber!!!!
 
The idea is to smooth out any ruff edges or sharp edges to prevent hot spots that my casue pre-ignition.

You'll also might want to look into thermo coatings on the piston tops (Crown) and cylinder head chamber.

P.S. I'd go for the bigger cam myself and use a slightly thicker gasket. Just don't loose the quench effect. It is important in this type of set up.
If, IMO, you use the thermo coatings on the piston and cyl. head chamber, you might, MIGHT very well get away with 87. Otherwise, you'll need 89. And have the timing set to where you want it.

Do not retard timing to suite octane goals. This is a big power robber!!!!

The point of edge-radiusing is not only to just smooth sharp edges, but to make a noticeable "radius" that helps pull the flame front into the quench area, making better use of the entire bore. Also, I'm not talking about retarding timing to quell detonation; I mean I won't need as much overall timing advance to make max power because combustion will be quicker and more complete, adding even more detonation resistance because there will be less time for "bad" things to happen in the combustion chamber.
 
I figured I would just mention that, not to you directly, but as an in general for all. I think that you know where your going with this.
Do not be insulted, sorry if I did so, didn't mean to do that.
Again, sorry.
 
I figured I would just mention that, not to you directly, but as an in general for all. I think that you know where your going with this.
Do not be insulted, sorry if I did so, didn't mean to do that.
Again, sorry.

Oh, no, that's okay, I knew you meant no harm. Just tryin' to make myself clear, that's all :-D
 
MOPE... Singh isnt a member on any site I know of...lol. You talk to the few who use his ideas. They are called Singh grooves for a reason.. a radius is a rounded edge. The groove is a directional surface feature, and the technology is 80s vintage. Nothing new. You're doing what a lot of guys here and elsehere do. What did your friend tell you do do about the piston and your choice in machinist?

back on topic... I am 100% with Needsaresto. K.I.S.S. You will get much mroe power from great machining and stock parts, than big dollar parts and skimping to have the money for them. Cool Dad/daughter build too. I like teh XE268 cam, or the larger Summit brand (Crane...)
 
Thanks Adam. Forgot which mufflers Kyle got. He was talking all sort of mufflers at the time.

The engine made 347hp and 395 tq on a dyno. Heads are the bottleneck. These were 587 casting with some bowl/runner clean up. I think it had some more HP available in the tune, but, didn't have time to mess with it. It's a good 1hp per C.I. combination. I think we are going to hook up an LM1 and RPM converter to the car to get the carb dialed in.

With a bigger camshaft, 400hp isn't out of the question. This engine needed to be a nice street piece and work with a max 2500 converter and 3.23-3.55 gears.


Just for kicks I did a little digging in my magazine library. Mopar muscle did a build over 4 issues back in 2000. 280H cam, smog heads ported out, stock bottom end with fed mogul 116 hyper pistons for 10:1.Torker II single pane?! intake,prolly looking to boost h.p #'s with it.Made over 400lb's of torque and 395 h.p

Also found a build with a stock 360 and stock magnums which made over 400 h.p .Again a bigger cam.

So yes I have to agree 400 h.p is easy, but fuel mileage would drop.

With the price of gas being so stupid, I think it's time to switch to an electric motor and load the trunk with batteries.
 
Just for kicks I did a little digging in my magazine library. Mopar muscle did a build over 4 issues back in 2000. 280H cam, smog heads ported out, stock bottom end with fed mogul 116 hyper pistons for 10:1.Torker II single pane?! intake,prolly looking to boost h.p #'s with it.Made over 400lb's of torque and 395 h.p

Also found a build with a stock 360 and stock magnums which made over 400 h.p .Again a bigger cam.

So yes I have to agree 400 h.p is easy, but fuel mileage would drop.

With the price of gas being so stupid, I think it's time to switch to an electric motor and load the trunk with batteries.

Sounds like more porting, single plane, bigger cam. I'd expect more power out of that than the one that we did.

If those were dyno'd at westech, that may be where the increase came from. I've seen an engine that made ~450 on westtech's pump, make 415 on another. I bet that 360 build that was done for my friend would dyno in the 370-380 range at WT. Unfortunately, dynos are a lot like flow benchs, no two are exactly alike.

To add, the dyno that was lower on power, has been closer, as in, almost spot on to the MPH/weight calculators for multiple engines. It was also very close to the camquest and DD numbers, too. I'll believe the numbers of the "conservative" dyno. Dyno numbers are sometimes like having to listen to two guys brag about their johnson. Bigger is better and yours ain't big enough. :)

Moper and needsaresto are right too... keep it simple, 107's, xe268H. Hard combo to beat for a street car. If you chase HP, your doing yourself a disservice. Build for intended use.
 
MOPE... Singh isnt a member on any site I know of...lol. You talk to the few who use his ideas. They are called Singh grooves for a reason.. a radius is a rounded edge. The groove is a directional surface feature, and the technology is 80s vintage. Nothing new. You're doing what a lot of guys here and elsehere do. What did your friend tell you do do about the piston and your choice in machinist?

back on topic... I am 100% with Needsaresto. K.I.S.S. You will get much mroe power from great machining and stock parts, than big dollar parts and skimping to have the money for them. Cool Dad/daughter build too. I like teh XE268 cam, or the larger Summit brand (Crane...)

These aren't Singh grooves I'm talking about. It's simply rounding the edges of the combustion chambers a bunch. The guy who "came up" with it is "dana44" on the allpar.com forum. In fact, he says that Singh grooves actually might not work as well as serious rounding of the chamber edges and gives a big explanation why he thinks so (has to do with turbulence and how it may actually mess up complete combustion).
 
I'm not sure what your taking about. I know the Singh thing. I think the best you can do for a chamber is coat the piston tops and cylinder head chamber that has been smoothed out. (Zero gap rings are a great plus.)
 
I think this will give a pretty good explanation of what I'm trying to get at. I quote this from a thread on the allpar.com forum entitled "dana's edging", and this is a post by dana44 talking about his theory on edging and other things like singh grooves, arguing with another member (mpgmike). He is talking about engines in general also, not just old Mopar V-8's.

"Mike, when we talked, I thought I explained that you were going to the trouble to port a set of heads to improve the flow from carb/TB to the combustion chamber, and by putting grooves inside the combustion chamber, you were upsetting a flow balance of making things as smooth and streamlined as possible, which is the goal of porting a head. I also talked about the carbide burr cutter texture which makes little cups about the size of a grain of rice which takes the fuel and air and causes a ripple which takes and keeps the fuel/air suspended at low and medium rpm levels, upper rpm levels don't matter because velocity itself takes care of suspension and we agreed on that. We talked about the fact I thought the grooves took away from the flow because it causes a hard chatter and actually catches the fuel and forces it to attach to the lynz grooves cut into the head port itself, I knew there were some things that weren't right so I guess I am saying, yes, there is a problem.

With that said, if you recall the original engine you did this on, a slant 6, and later a motor home V8, they were both carbureted engines and once the lynz were cut at the base of the carburetor underneath, it then had to travel roughly 7-9 inches through the intake before it came to the back side of the intake valve and into the head. Plenty of time for the fuel to stabilize within the air and be super atomized. With fuel injection, literally, the fuel is being shot into a torment of the intake port and it is literally sticking to the lynz noted by the yellow tinge of the intake runner where the injector is, not normal color as a regular head, the black garbage is from a bad port that does not flow properly and the fuel is puddling and getting cooked or coked on the dead flow spots of the stock ports. It is atomizing, but it is atomizing not because it is in a slip stream, it is atomizing because of the ripples of the wall, which saves you a whole lot of money and time in doing lynz that isn't doing any better than a good port job with the proper carbide burr surface. You would actually get the same results if you used an 60grit sanding disk believe it or not. Something that may help, believe it or not, is if the ports are prepared properly, but the intake itself has the lynz given the air itself needs to be turbulent to catch the fuel and it would be patternized to flow smoother once the fuel is injected into it. In other words, the lynz are too late for them to properly work in my estimation, which is why you aren't building 90mpg 2.2/2.5 engines out there. If the lynz did work that way, that would be the standard and it isn't, is it?

I have no qualms of you edging combustion chambers, but the singh grooves are messing up the flow potential of being able to burn a lower octane fuel with edging and still produce more power than before with even lower (slightly) compression, and from every test I saw and have read, singh grooves do nothing whatsoever to increase horsepower or torque, they in many cases dropped slightly or nothing at all. The only reason I can see that the cylinder temperature is reduced is because the flame is actually being blown out or pushed away from the opposite side of the cylinder and thus not burning as hot. Do it with the 2.2 with the 2.5 pistons on an 89 and above common block (I may have this wrong....there is a combination of the common 2.2/2.5 where you can get a 2.2 with 12:1 compression by the combination of piston/rod/newer block or something, good deal), but the grooves are forcing a bad woosh that is trying to be alleviated through the edging. Anyway, edge a head properly with the high compression and you will have great mileage, a couple mpg to 5mpg or more better than a stock engine and an additional 35hp on a stock everything else, no problem, might be more, haven't been able to do it myself, might get the time after this deployment in the spring. The goal is to have a higher compression engine that runs on the cheapest fuel, retains at least or better gas mileage and has better performance and even sounds better than stock.

In other words, each and every little thing, porting, edging, singh grooves and lynz are all good things by themselves, but porting and edging are the same and the lynz and singh grooves take away from what porting and edging does, namely improving the flow from point A (intake to behind the intake valve) to point B (inside the combustion chamber, so think of edging as combustion chamber porting) then out the exhaust. Shoving air through a ridged tube and then put it into a combustion chamber that has been hacked up, is that good flow conditions, flame travelling all over the place without a controlled pattern (I think not).

Since I did not nor do I intend to patent my technology, you can still use it, can't stop you from doing it, but too many combinations are ruining the soup. Singh grooves, blowing out the flame, prevents it from allowing the flame to travel all the way across the piston and cylinder head. If I wanted an engine with a burn pattern on the piston that is only 3 inches on a 4 inch piston, I would get a 3 inch bore block. In other words, limiting the flame travel from making it all the way across the piston is a waste of bore, (and the bragging that the exhaust gasses are cooler, no kidding, blowing out a flame partway will do that, kind of like an oversized dome piston with the sparkplug not being able to reach the other side because it is too tall thus producing less power because only 20percent of the piston area is burning) grooves do that by the wooshes whent he piston makes TDC and forces everything out of the quench area. The only thing really saving it and actually making power is the edging, which is allowing the exploded gas wedge into the quench area (small after edging thank god) and put force all the way against the piston top, causing, you guessed it, more hp and torque naturally. Why do you think the guy that used to run 30psi gets the same results with 20psi now? Flow potential, not lynz or grooves, but I already gave that promise. It also now makes a smaller engine sound like a larger enigne because on a head that hasn't been edged, about 70percent of the piston is being exploded on, after edging, the potential is there for 90-97percent, meaning there is a gain in the explosion/combustion, thus a larger piston utilized. Get it?

Sorry about it being so long, others may enjoy, hope you learn from it or will at least try a head without lynz or grooves first, then compare it afterwards with them (hard to do it the other way around). I have a couple guys that have asked me to port their heads after my return in the spring, might even retire and do it professionally. I know I have a couple motorcycle shops asking me to work for them, engines only, might just do it. Already got the tools.

I see it as taking a pretty well ported head and then taking a rasp to the ports and a hatchet to the combustion chambers. Kind of defeated all that good work."

Things like "powre lynz" that dana44 is referring to are grooves cut into the intake ports to supposedly help keep fuel suspended.
 
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