Engine build help 318

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Dave999
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Re: Engine build help 318

Post by Dave999 »

you don't have to do this but you can

if you take the freeze plugs out of both blocks you can measure or check the distance between the cylinders. (unless of course you have a Siamese block), the wrost you will find is they are both the same. smaller gap block has thicker cylinder walls. this tends to affect earlier blocks, they start off fat, and as feedback and warranty claims come in, or financials take their toll the wall thickness gets reduced to what "just works" the tooling is modified to save a couple of cents in molten iron per block.

or maybe its the reverse worn tooling = fatter walls and the last block made with that set of tooling is fatter in the cylinder wall. both theories get bandied about.

the factory did look for or create thicker walled blocks anyway for police motors etc so maybe the tolling for them just got used in the general mix after contract completed

fat wall thickness on the bore gives better results provided there has been no core shift.. look for consistency between the casting for the bores through the holes and if in doubt get it ultrasound tested to see how thick the walls are.

i have an early hemi 6 and a late hemi 6 early hemi 6 and i can't get a 10 mill spanner end between the bores late block it fits no problem, but i only found this out after i had built the thin wall block... i would have used the other one had i known at the time.

fat walled block in some cases from some engine plants = better bet for higher power motor. there is little rhyme or reason to it so worth checking

check also the bridges from the pan rails to the main bearing journals they vary a block with fatter less knarly better cast less casting flash is going to be a better bassis for a stroker. you are a prime position having 2 dismantled motors to use the best block for the stroker build


Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Dave999 wrote: Mon Dec 07, 20 3:58 pm 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

Dave
;) :-k
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Blue wrote: Mon Dec 07, 20 7:38 pm 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.
Your a bad man Blue :shock:


OMG loads of things to buy, spent 40 mins, looking through all the goodies. It was like playing gran turismo, but for real will all the mods you can get :plymouth:

Had a basket up to £8,500 + :pale: :?

Didt spend that just what I would have liked to buy
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

Dave999 wrote: Tue Dec 08, 20 12:14 pm you don't have to do this but you can

if you take the freeze plugs out of both blocks you can measure or check the distance between the cylinders. (unless of course you have a Siamese block), the wrost you will find is they are both the same. smaller gap block has thicker cylinder walls. this tends to affect earlier blocks, they start off fat, and as feedback and warranty claims come in, or financials take their toll the wall thickness gets reduced to what "just works" the tooling is modified to save a couple of cents in molten iron per block.

or maybe its the reverse worn tooling = fatter walls and the last block made with that set of tooling is fatter in the cylinder wall. both theories get bandied about.

the factory did look for or create thicker walled blocks anyway for police motors etc so maybe the tolling for them just got used in the general mix after contract completed

fat wall thickness on the bore gives better results provided there has been no core shift.. look for consistency between the casting for the bores through the holes and if in doubt get it ultrasound tested to see how thick the walls are.

i have an early hemi 6 and a late hemi 6 early hemi 6 and i can't get a 10 mill spanner end between the bores late block it fits no problem, but i only found this out after i had built the thin wall block... i would have used the other one had i known at the time.

fat walled block in some cases from some engine plants = better bet for higher power motor. there is little rhyme or reason to it so worth checking

check also the bridges from the pan rails to the main bearing journals they vary a block with fatter less knarly better cast less casting flash is going to be a better bassis for a stroker. you are a prime position having 2 dismantled motors to use the best block for the stroker build


Dave
:thumbright: Gona look at both
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

A few questions :-k


Should the flywheel have spring washers ? and or be locktighted ?


Will the water drain bolts in the block snap off? 8-[


How do I get a hydrollic lifter to spin?

Thanks :)
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Dave999
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Re: Engine build help 318

Post by Dave999 »

i used Chrysler flywheel and flex plate bolts

ricks mopars on ebay has NOS

i wire brushed the crank hub till it shines
i wire brushed the centre of the flywheel till it shines
promotes proper friction between the two

i bolted on flywheel no washers.

why? because the Chrysler bolts have what some people term a Cosworth Ring... obviously Chrysler didn't as cosworth probably didn't exist at the time

a Cosworth ring is a narrow ring area of removed material say 1/2 mm wide, either in a circle that bisects the bolt holes in the flywheel mounting face, it follows the PCD exactly, or it is removed from the back face of the bolt head on a big headed bolt.

the idea is that you reduce the surface area that the bolt clamps down to by removing some material from the interface between the two. which massively increases the pressure between bolt head and the thing to be clamped (pressure being force/area) thus the likelihood of the washer-less bolt coming undone is massively reduced. the higher the pressure the higher the friction between bolt head and what it is clamping. up to a point....go too far and it doesn't work

Chrysler flywheel bolts have a large head and you will find there is an area with material removed from the face of the head between the bolt shank and the outer perimeter of the head....same Principal remove half the surface area and provided the material is hard enough you double the friction between the 2 parts.

if you want to locktite. put in first 3 or 4 bolts dry, do up to torque . locktite the rest and put them in, up to torque then take out and loktite the first 3 or 4 . stops lokitite migrating between flywheel and crank boss, which ruins the friction between the two.


2) probably if you can get away without snapping something i.e not removing...its worth doing

3) the cam lobe is offset from the lifter bore, the lobe covers only 7/8 of the face, or maybe less. As the cam turns the lobe runs on lifter face off centre and turns the lifter. Cam lobe is also higher on 1 side than the other and lifter face has a slight dome, this all helps to 1) turn the lifter and 2) keep the cam driven back in the block.3) as a reaction to the opposite direction forces created by driving oil pump/dizzy

put a white stripe of paint on the rocker ends of your pushrods
start it with the rocker tins off
watch the pushrods turn when its running. pushrod only turns if lifter is turning
if all lifters turning the chances of cam wipe out during break in is massively reduced

a lifter that has the same area wiped by the cam lobe over and over again just gets chewed the face needs time to recover and the zddp in the oil needs time to fuze into the surface. think of it as like work hardening, you want consistency across the lifter face

you are looking for any stiff ones that do not turn. if a lifter does not turn, stop and find out why.

easier to do when building
put engine on stand
angle lifter bore down
put plastic or cardboard tray underneath

oil lifters drop into bore
few seconds later it should fall out the other end. don't let them clatter together pick em up before doing the next one

if not bottle brush the bejeesus out of the lifter bore. its sticky with varnish
or check for nicks or burrs lifter and bore entry or exit

Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
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Dave999
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Re: Engine build help 318

Post by Dave999 »

https://www.ebay.co.uk/itm/NOS-Mopar-Fl ... Sw8oFXyM2Z

pre loktited as well....Nice

you can pay a fortune for nice 12 point Nascar rated ARP but they have a flat head a NEED loktite and you are not supposed to use them more than x number of time

the chrysler stuff does the job.

Dave
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TIB3300
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Re: Engine build help 318

Post by TIB3300 »

As always thanks,


I have new information regarding the lifter.I will put up in my build post #-o
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Dave999
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Re: Engine build help 318

Post by Dave999 »

yeah i saw

nice find. saved the cam, with that

i never had a v8... these things pop up and catch you when you least expect it

Dave
The Greater Knapweed near the Mugwort by the Buckthorn tree is dying
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