Engine build help 318

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DaveB
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Re: Engine build help 318

Post by DaveB »

No, you can put hydraulic roller lifters on a hydraulic flat tappet cam.
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Dave999
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Re: Engine build help 318

Post by Dave999 »

keep it simple

i think dave means you can't.... CAN'T not can

a Roller cam is a made from a different material everything it drives needs to be matched to avoid ware
you will need to do something about oil control at the lifter gallery pipe mallet drill potentially sleeve lifter bores
they are heavy and tall. springs retainers valve length angle of pushrods and clearance
they have a roller in an open section at the bottom that can expose the lifter bore oil hole and that results in no oil pressure. i.e in normal operation or if they bounce
you may not have space for the link rods and any alternative "keyed" or clip retained lifters need appropriate shaped sleeve for the key or mount for the clip
the lobe shape is very aggressive compared with flat tappet cams you need a lot of spring to control.
running roller lifters based on the above is a big investment in lifter, cam, springs, work on block, oil pump dizzy drive, potential fuel pump. etc etc

solid flat tappet or hydraulic flat tappet best in this case.
for an aggressive hydraulic which is a bit of a nonsense way of putting it (they can't be) you could think about anti- pump up or variable bleed lifters. potentially snake oil but loads swear by them.
A solid will need adjustable rockers


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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Cheers no rollers then :thumbright:

Heres the crank out of the UK engine . am happy to go again with this crank
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DaveB
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Re: Engine build help 318

Post by DaveB »

cant,cant not you can :lol:
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Three Questions ? :read2:

If a bore is oval ? --------------------------- What real problems will you have ?
If a bore tapers ? ----------------------------- What real problems will you have ?
If a bore is slightly worn over tolerances? -- What real problems will you have ?

Over the short term, with a non performance engine.

Not saying this is what I intend to do, but just wondered :-k
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Dave999
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Re: Engine build help 318

Post by Dave999 »

poorer ring seal and lower compression in all cases.

if its oval it will be oval in the thrust direction and more on one side than the other due to the offset of the pin in the piston
there is some ovaliaty anyway that is pulled into a circle by doing up the head bolts and main caps.. but you need to be pretty hot with the bore gauge to spot it and only really on a new or just machined block. on a old used one how can you tell if its this or just general ware

taper depends where, but if its to spec. at the bottom, and tapers to the top. Its tapered so you have too much clearance at the point where you really do need a good ring to wall seal.. however given that the combustion gases are at this point blasting down into the ring grooves the rings are probably slammed harder into the wall here than at the bottom. hence the taper and perhaps hence some kind of saving grace, ring pressure in the worn zone will be greater

slightly worn puts you in the category of just about every motor that has done real life mileage. not the end of the world . however if it took 100,000 mile to get this worn building it with new rings now means you will be building an engine with mileage life of something less than that, by quite a margin.

id suggest if you put the motor back together using all the same parts , except you got new pistons rings and rebore you'd probably building a higher powered longer lasting motor than

if you

built the motor with new bearings new cam of street/driver style new springs etc and stuck with the worn bore and new rings.

having a round bore is key, a big old worn BUT round bore is better than an oval one gives you options on getting up to the next size

you can get a re bore and hone. ideal if the bore is not round or is scored and damaged. it should be done with the main caps on and a torque plate bolted on in place of the cylinder head
however find a 318 torque plate.... :)

however again

if you can find a shop with a particular type (read expensive and robust) hone, who is willing to do it
they can hone to the next size up (like they do with 2 stroke barrels) maintaining to a large ish extent the general shape of the bore, its a slightly more forgiving process and can be used if you have no torque plate...

sling it in the mix and ask them to measure to see if viable you might end up with a rounder bore that way, just a bit bigger for new pistons.

ask anyone and they all say they got it re-bored, some at least won't know that it was just honed out, depends on the shop and the engineer and what questions they asked.

takes longer is more awkward in one way, but less time spent setting up 2 machines a minimum of 8 times each for a boring then hone

Dave
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Dave999
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Re: Engine build help 318

Post by Dave999 »

PS getting some bloc work done more or less means it will go through a parts washer..

something that in isolation will cost you money anyway, unless you like scrubbing with paraffin diesel or degreaser and a washing up brush for hours n hours :)

PS i have never found anyone with the "internet legend" a HOT TANK. health and safety seems to have removed oil drums filled with acid or alkali or some special heated cleaning pickle juice, from industrial areas... :)


people say in posts the internet wide "oh just get it hot tanked".....my question is always how? who? where?

PPS crank looks alright doesn't it, someone might have aggressively measured that rod journal with micrometer, doesn't look like anything to be too concerned about will p o l i sh
itself in use.

you can't write a word ending SH and a word starting IT without the swear filter getting in the way... its a a bit Bananarama!

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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Thanks Mr :thumbright:

been busy today over 160 measurements on the bores did everyone at least 3 time 3 1/2 hours sat on a stool in the garage even with heating still fkn frozen now. :(

This is what I have
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Re: Engine build help 318

Post by Dave999 »

Cylinder Bore (standard) 3.910"-3.912"
Cylinder Bore Out-of-Round(Max. allowable before reconditioning) .005"
Cylinder Bore Taper (Max. allowable before reconditioning) .010"

sorry still at work so haven't looked too hard its worn as you expected or was bored for a none standard piston that demanded greater clearance
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Dave999 wrote: Fri Dec 04, 20 7:04 pm Cylinder Bore (standard) 3.910"-3.912"
Cylinder Bore Out-of-Round(Max. allowable before reconditioning) .005"
Cylinder Bore Taper (Max. allowable before reconditioning) .010"

sorry still at work so haven't looked too hard its worn as you expected or was bored for a none standard piston that demanded greater clearance
:thumbright:
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Building a 318 stroker

Is there anything I need to know first ?

I can find places on the net, but I would like advice from you guys who have previous experience / confidence in a place
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Re: Engine build help 318

Post by Dave999 »

never built a stroker so will have to bow out on just these points

1) you will potentially need shorter pistons... or at least pistons with a revised pin position. you may want to think about rod ratio, can't have skirt hitting crank web ..... Buy a kit crank rods pistons with the hard work done is the easier option.
2) bottom end needs to be in great condition
£) this is no longer a rebuild this is an engine build.... be prepared to check everything doesn't hit everything else.... pistons to crank rod cap/ bolts to bits of block or bits of cam, valves to piston.




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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Dave999 wrote: Mon Dec 07, 20 10:40 am never built a stroker so will have to bow out on just these points

1) you will potentially need shorter pistons... or at least pistons with a revised pin position. you may want to think about rod ratio, can't have skirt hitting crank web ..... Buy a kit crank rods pistons with the hard work done is the easier option.
2) bottom end needs to be in great condition
£) this is no longer a rebuild this is an engine build.... be prepared to check everything doesn't hit everything else.... pistons to crank rod cap/ bolts to bits of block or bits of cam, valves to piston.

Dave
Thanks
Have decided to build two engines, a standard engine for now with new pistons and build a stroker over the next year or so,

Yes was going to buy a complete kit crank rods pistons :thumbright:
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Dave999
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Re: Engine build help 318

Post by Dave999 »

So if the block above is short term you could just hone it and put the pistons back in... see how it goes.

and the stroker in the other block will want proper bore and hone to get the best out of your investment.
be good idea actually to choose the block with the tallest deck to give you flexibility on the stroker build as its is going to be the keeper but i guess the one that really needs the rebore should be the one that gets it

the one above does needs one, but not as much as the previous one, and for minimal outlay you could build a motor that functions with it

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Blue
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Re: Engine build help 318

Post by Blue »

I've been using Hughes Engines for my small block needs for a few years now. That's where I'd be going for a stroker kit, there is a wealth of tech on thier site too.
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