Another 318 build, and questions. (LONG)

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66durgederp

"pull hard, itll come easy"
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so after discovering a nasty crack in my current 318's block, opportunity showed its face to build up an engine, why? because i can, and I want it done my way. however im trying to keep cost on the down low as much as possible without cutting corners. ive never truly built my own motor before for myself, (Ive only done diesels, DT466's, 7.3's, 671 and series 60 detroits) so naturally i have a few questions and inquiries. please critique my plan and pointers are muchly appreciated.

Ive acquired an assembled FRESH, never fired .030 over 77 vintage 318 block with .010 under cast crank, factory rods, and aftermarket aluminum pistons of unknown make. it was for a hotrod project and the guy went chevy instead, his loss. The price was right and i couldnt pass it up. i will disassemble the short block and have everything checked, since i dont trust other peoples work without knowing whats been done. so first off, have the block squared up, and have the mains checked for straightness, line bore if necessary. use the existing bearings granted everything checks out ok after plastigage-ing. I just put a new balancer on the existing engine 7 months ago, its a factory replacement unit from dorman. Ill be running it as well.

I will be running the 87 vintage 360 heads 1.88 intake 1.60 exh currently on my cracked mill. ill get the valves re-faced, seats reground, and guides checked. along with a home done mild port job via the sticky thread in the smallblock tech forum. so as for pistons, i was leaning towards Keith Black KB399-30's, 1.81 inch compression height, +6cc dome to keep the compression from the dumps (shooting for 9.5:1) and avoid extreme block/head machining. Moly rings, with .0065 top ring end gap. now these are hypereutectic pistons, i will NEVER be running the "go-juice" in this thing. im after a snorty, yet streetable engine, that makes respectable low end power. most of its run time will be in-town and some highway long range (100+ mile) trips, and the occasional weekend tire killing sessions. Are these pistons up to par for what im trying to accomplish? or would flat top forged units and lots of head/intake milling be a better option?

for a camshaft im leaning towards comp cams xtreme energy K20-223-3 kit, comes with adjustable dual roller timing set, springs, lifters, keepers, locks, valve guide seals. cam specs:
Basic Operating RPM Range: 1,600-5,800
Intake Duration at 050 inch Lift: 224
Exhaust Duration at 050 inch Lift: 230
Duration at 050 inch Lift: 224 int./230 exh.
Advertised Intake Duration: 268
Advertised Exhaust Duration: 280
Advertised Duration: 268 int./280 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.477 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.480 in.
Valve Lift with Factory Rocker Arm Ratio: 0.477 int./0.480 exh.
Lobe Separation (degrees): 110

The transmission ill be running is a lockup 904, with a pro-king 1800-1900 stall converter, and the rear end has 2.94's currently, may step up to 3.23's with the axle swap coming in the near future. for camshaft selections sake, is this unit excessive? is there anything super specific i should pay attention to? what specs will affect bottom end? Ive been told that while degreeing the cam, if its set 4 degrees retarded that will help out the lower end power. This true?

Ill run all the current tin-work from my existing engine, factory windage tray, oil pan, valve covers, timing cover, brand new water and fuel pumps yadda yadda yadda...

oil pump, melling high volume unit, or is that a bad idea with a factory 5qt pan? do these engines run into higher rpm oiling issues like ferd FE's? and if so, approx what rpm? ill maybe tap into 5000rpm but on extremely rare occasions. Will factory bottom end parts be stable at that rpm? when complimented with ARP knurled rod bolts and main cap studs?

intake manifold.....I have a "cop car" cast 4 barrel unit currently, it has a .75 inch higher carb flange than standard 4 barrel intakes, from what i can find thats the best info i have. 360 sized ports, to mach the heads. since im not racing, does anyone see a problem with this intake? or should i run an old eddie performer 318/360 manifold that i can get for el-cheapo? topping these off will be a 650 CFM holley 4175 spreadbore with a 1 inch phenolic spacer.

Exhaust manifolds: factory cast units, drivers side, 74 360 valiant manifold (they WILL fit in an early-a by the way) passengers side 360 center dump manifold from my 73 D100. im too much of a cheap *** to get dougs headers or spitfires right now, and probably for a long while. these "logs" will have to do. The exhaust system is 2.25 head pipes for the first 1.5 feet, then 2.5 inch all the way out to the diff. Ill have an "H" pipe put in later on, and tailpipes too.

Ignition: MSD 6A, recurved and phased stock type distributor, 34 degrees total advance, all in by 1800-2100 rpm. NGK GR4 V-powers, 8mm wires and a MSD Blaster coil.

gaskets. good ol fel-pro, however for head gaskets, is it advantageous to run mopar performance or cometic multi layered steel units over fel-pro permatorqe gaskets? do i really need steel head gaskets with iron heads? or would that be an un-needed expense?

Theres the basic run-down for whats been rattling around in my head :evil3: critiques, recommendations, and pointers are more than welcome. many thanks!!
 
That cam should work well, I think if you degree the cam to have more down low you will lose top end power which is where the 318 comes to life. with some converter I don't think you won't need any more downstairs. I also think a stock oil pump would suffice. You don't need MLS head gaskets, it would be a huge waste of money on this motor, stock felpro will do the job fine. I'm not a big fan of stock iron 4 barrel manifolds. Some do work okay but you could get a lighter aluminum one that performs better.
 
better check your ring gap clearance.. .0065 is a death wish on a hyper piston...it is more like the 3.94 x .0065 = .026
 
Running clearances and top ring gap on KB pistons are a bit different than OEM specs. Honor the KB specs.

I'd degree the cam per the cam card, no need to advance.

Since you're running a lockup, why not a higher stall RPM? 2300-2500 wouldn't be unreasonable.

No need for HV oil pump, factory LA engine oil system just fine. Put that money towards windage tray.

That intake has the advantage of being free if you already own one. Performer RPM would be my choice. Same with carb. I wouldn't go out of my way to run a 4175.

Otherwise seems reasonable. Down the road you would benefit from headers, but the cost.
 
If you can find a copy of the February 2009 issue of Hot Rod Magazine Steve Dulcich built a 400 HP 'teen using parts that are very simular to what you are proposing. This would be good reading for your build.
Bob
 
gracias! i read up on both of those builds, makes me feel better about what i planned on. however now im wanting to lean towards the existing flat tops and milling my open chamber later 360 4323345 casting heads .040 to .050 (8 to 10cc's, 69 to 64 roughly) to keep compression up, granted the slugs arent el-cheapos, if theyre no-name units then im going to get KB167's. ive read up on domed units, they get hotter because theres more material to withold heat, makes sense, and can be no bueno, i figure if i can shy away from it, its one less thing to worry about.

On the flip side, my lovely open chamber heads arent worth a hoot to deliver any sort of quench, wich makes zero-decking essentially useless, and im not planning on going through numerous sets of "302" or magnum heads trying to find a set that isnt cracked, been there sunk that boat, and im not forking out 1200 bucks for new RHS units, im too damn cheap, scottish, and "poe"....so now im back to the domed KB399's and minimal machining of my current heads to keep compression up....but with no quench-face in the head....it will be much more prone to detonation issues right? How in the world did ma-mopar keep detonation to a minimum with zero-quench heads without dumping the pistons a mile in the hole?! ugh....this shtuff is confuzzling and is driving me nuts....HELP!!!...please!!

Im going to stick with the XE268 cam, seems to be a real snotty runner, exactly what im after. I always run 91 in my rigs, so 9.5ish (9.1 minimum) should be fine right? if not i have some close friends who work at the local airport....i have access to 112 low-lead for 4.19 a gallon.....dual fuel system? yes yes?
 
1st,no on the H/ V oil pump,way yes on Mopar part number 3690715.
You need"quench", a spot that gives the engine,anti detonation properties.The deck clearance, .038 to .48.This works on all domestic v8's.Study some on it,you won't need Av - Gas. Nice combo,lose the domes.....
 
You won't need anything to avoid detonation with 9.5:1.

If you want 400hp you willl NEED a single plane intake and some port work.

Despite the magazine articles findings, a 400hp 318 is actually really really difficult and expensive to build with factory iron heads.

(mine made 352hp but by all rights *should* probably equal or surpass those in the magazine builds.)

KB399's are good but be careful with the ring gaps. And if you DO get detonation for even a few seconds they're history in the making

The XE268 will run out of puff about 5400RPM but make really nice streetable torque.
 
I think your combo sounds pretty good. If you wanna save money Id go with a nice used aluminum dual plane intake and a cheap set of used headers. With some mild head work on your combo it would be a nice cruiser and have some balls to boot. Just make sure your ring gap is right and your good....
 
many thanks, im really digging this input!!! ok so i did some serious reading up on quench (sometime when abodybomber posted about it, thanks haha) and dynamic compression ratio to determine the required octane. My current heads average 74cc chamber volume un-milled but can be as high as 77....i WILL cc out my heads when i rip this monster apart. So thats what im running with for spec's sake, and a fel-pro head gasket 4.18 bore and .039 compressed, and XE268's intake spec, closes 60 degrees after bottom dead center, and zero-decked, @3000ft above sea level. with the KB399's my dynamic compression is 7.37:1 and static is approx. 9.7:1, with KB167's dynamic is 6.36:1 and static is approx 8.45:1.

seems to be and general majority here are against domes, thats great, now my main brainfart is, how do i "build" quench into this thing with my existing heads? Does anyone know if these things can be milled a reasonable distance to move the cast-in "quench pad" within .040" without some fancy razoo head gasket? or is this a lost cause? If it is a lost cause, any ideas what i can expect for downfalls or issues? if any? And zero decking would be useless at that point, right?

Second question, since im running the largest chambered 360 heads, i can have them milled .040" to remove approx 8cc's, or .050" to remove 10cc's, removing 8cc would take the static to approx 8.9:1 or 9.19:1 (depending on what my heads CC out at)

Removing .050" would take it anywhere from 9.09:1 or 9.4:1 static and 6.88:1 or 7.13:1 dynamic.Ill be running hydraulic lifters for simplicitys sake, and if i do have the heads milled that much, any recommendations on kickass do-it-yourself pushrod kits?
 
I talked to the machine shops here around town and the general concensus on building quench into my particular combo will take some serious milling and very deeeeep pockets....so ive come to the realization that ill have to do without, and after reading up on numerous open-chamber head builds on 340's and 360's i guess its not a HUGE deal for a weekend cruiser/daily driver granted decent fuel is used, or so im told. (i run 91 in all my stuff)

so, heres what ive come up with after jockeying around numbers for a better part of my day. the heads i have (345's) cc out on average around 74cc's, so thats what i did my baseline computing with, that and ill be using fel-pro head gaskets, 4.18 bore and .039 thick when compressed. Im going to use the KB167's because they have been proven to be a great unit in many builds, and the price is right. If i have my current block (.030" over) zero decked with kb167's, and mill .030" off the heads, removing approx 6cc's, setting the head volume at 68cc's, then my static will be around 9:1, and dynamic will be around 6.81:1.

OR i could go nuts and have .060" milled off the heads, removing approx 12cc's, taking my heads to about 62cc's, and that would put my static compression at 9.6:1, and dynamic compression to 7.32:1. that i could be completely happy with.

main new question in point here that i have now is.....now much can be milled from the heads after the approximate .012 is milled from the deck to zero deck, before it starts to require custom pushrods? some sources ive found say .060", some say .030".....
 
If you have not bought head gaskets,check out Mr Gasket 1121g's .Compressed,.028 thousands.
 
If you have not bought head gaskets,check out Mr Gasket 1121g's .Compressed,.028 thousands.

i did check those out actually! but then it occurred to me, if .040 quench is ideal, i know my engine will NOT have quench, but there IS that little area where the heads will hang over the cylinders on the very edge of the bore, and if i zero deck this monster (i know its useless without quench, but if i want to swap some RHS or eddie heads later on i can build it with quench if i want to) then i will only have .028 clearance on the very edge of the pistons, and that tight of clearance has me a bit scared, so i opted for the fel-pros....just to be safe. Id really hate to have a piston kiss the head. but thank you Abodybomber!

Also, would anyone out there have a program that can determine the octane rating for a certain engine combination? I cant seem to find one and im thinking its for good reason, seems the general answer ive seen is "it depends on the engine" well i have pretty rock steady plan for what i want to do, specs and everything, but cant find a program or way to get a general idea...ill be running 9.42:1 static and dynamic with a comp XE268 will be around 7.14:1 at approx 137.03 dynamic cranking pressure. open chamber iron heads @ 64cc's...this seems to be whats killing me but i have to make do with what i have. would a 180 degree t-stat be better for this combo? ive heard too many horror stories about kb hypers and detonation killing them and now im freaking out...haha
 
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