318 upgrade ?

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Blue
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Re: 318 upgrade ?

Post by Blue »

You will also need to find a machinist that will do the work for a less than insane price. I was told yesterday £600 is the going rate to rebore a V8 block and same again to balance the rotating assembly. There must still be people out there that do quality work for a good deal less than that surely?
“It’s good enough for Nancy”
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Pete
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Re: 318 upgrade ?

Post by Pete »

TIB3300 wrote: Tue Jan 28, 25 6:44 am
Pete wrote: Sun Jan 26, 25 7:04 pm If you just wanted to improve acceleration and was not too worried about at higher cruising speed, a set of Numerically Higher gears is probably the cheapest fix for livening up a car, as with all modifications and projects - it depends on the overall objective.
Thanks, :thumbright:
The proviso on this is that the Torque Convertor is sufficiently "Slippy" and will not stall too early and make it very unpleasant to drive - the same applies to any Camshaft change, they all need to be a match package...
Pete Wiseman; Cambridge.

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Stu
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Re: 318 upgrade ?

Post by Stu »

Blue wrote: Tue Jan 28, 25 4:46 pm I was told yesterday £600 is the going rate to rebore a V8 block and same again to balance the rotating assembly.
Wowch! :shock:
24 hours in a day, 24 beers in a case. Coincidence? I think not…

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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

Pete wrote: Tue Jan 28, 25 4:55 pm
TIB3300 wrote: Tue Jan 28, 25 6:44 am
Pete wrote: Sun Jan 26, 25 7:04 pm If you just wanted to improve acceleration and was not too worried about at higher cruising speed, a set of Numerically Higher gears is probably the cheapest fix for livening up a car, as with all modifications and projects - it depends on the overall objective.
Thanks, :thumbright:
The proviso on this is that the Torque Convertor is sufficiently "Slippy" and will not stall too early and make it very unpleasant to drive - the same applies to any Camshaft change, they all need to be a match package...
Am running manual Ford T5 :thumbright:
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

mygasser wrote: Tue Jan 28, 25 1:46 pm 7ltr would be 427/428 ish so 408 isn't near that at under 6.7ltr, lol. 40 over on the 318 with the 4" stroker gives 392 which is a vintage hemi size.
neil.
just remembered they do a 392 gen3 hemi in modern chargers/challengers too these days, playing on the vintage vibe.
OK a 6.7 sticker then ;)
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

Dave999 wrote: Tue Jan 28, 25 3:58 pm this is probably a bad idea......

you will need to find the crank out of a 360 that someone has discarded because they went with a new steel stroker crank
you will need 360 heads that someone has discarded because they went for nice ally heads

you will need to deal with the internal external balance issue and turn down the mains
etc etc etc
https://www.forabodiesonly.com/mopar/th ... eap.19556/
Dave
Thanks Dave

Food for thought and looks like an interesting read, I maybe back to ask questing. As I don't understand some of it 8-[
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

Blue wrote: Tue Jan 28, 25 4:46 pm You will also need to find a machinist that will do the work for a less than insane price. I was told yesterday £600 is the going rate to rebore a V8 block and same again to balance the rotating assembly. There must still be people out there that do quality work for a good deal less than that surely?
:-k :pale:
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Pete
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Re: 318 upgrade ?

Post by Pete »

TIB3300 wrote: Tue Jan 28, 25 7:41 pm
Pete wrote: Tue Jan 28, 25 4:55 pm
TIB3300 wrote: Tue Jan 28, 25 6:44 am

Thanks, :thumbright:
The proviso on this is that the Torque Convertor is sufficiently "Slippy" and will not stall too early and make it very unpleasant to drive - the same applies to any Camshaft change, they all need to be a match package...
Am running manual Ford T5 :thumbright:
Ahhh!!!

A good drive spoiled then?
Pete Wiseman; Cambridge.

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mygasser
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Re: 318 upgrade ?

Post by mygasser »

Dave999 wrote: Tue Jan 28, 25 3:58 pm this is probably a bad idea......

you will need to find the crank out of a 360 that someone has discarded because they went with a new steel stroker crank
you will need 360 heads that someone has discarded because they went for nice ally heads

you will need to deal with the internal external balance issue and turn down the mains

etc etc etc

https://www.forabodiesonly.com/mopar/th ... eap.19556/



Dave
your first sentence there was about right, lol. :thumbright:
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

Pete wrote: Tue Jan 28, 25 7:54 pm
TIB3300 wrote: Tue Jan 28, 25 7:41 pm
Pete wrote: Tue Jan 28, 25 4:55 pm The proviso on this is that the Torque Convertor is sufficiently "Slippy" and will not stall too early and make it very unpleasant to drive - the same applies to any Camshaft change, they all need to be a match package...
Am running manual Ford T5 :thumbright:
Ahhh!!!

A good drive spoiled then?
Oh! no. I love the manual, one of the must have's was manual when I built it :thumbright:


.
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

mygasser wrote: Tue Jan 28, 25 8:31 pm
Dave999 wrote: Tue Jan 28, 25 3:58 pm this is probably a bad idea......

you will need to find the crank out of a 360 that someone has discarded because they went with a new steel stroker crank
you will need 360 heads that someone has discarded because they went for nice ally heads
you will need to deal with the internal external balance issue and turn down the mains
etc etc etc
https://www.forabodiesonly.com/mopar/th ... eap.19556/
Dave
your first sentence there was about right, lol. :thumbright:
Why? :read2: :lol:
mygasser
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Re: 318 upgrade ?

Post by mygasser »

TIB3300 wrote: Wed Jan 29, 25 9:23 am
mygasser wrote: Tue Jan 28, 25 8:31 pm
Dave999 wrote: Tue Jan 28, 25 3:58 pm this is probably a bad idea......

you will need to find the crank out of a 360 that someone has discarded because they went with a new steel stroker crank
you will need 360 heads that someone has discarded because they went for nice ally heads
you will need to deal with the internal external balance issue and turn down the mains
etc etc etc
https://www.forabodiesonly.com/mopar/th ... eap.19556/
Dave
your first sentence there was about right, lol. :thumbright:
Why? :read2: :lol:
''this is probably a bad idea....''
agreed as the cost and work involved would be too much compared to other 'better' options.
neil.
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Dave999
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Re: 318 upgrade ?

Post by Dave999 »

you are building a 349 in a 318 block
using a cast crank
the 318 block when compared with 340 and 360 is a little less robust.
and you will have to machine the 360 crank on the mains to make it fit, which takes the 360 crank main journals past...way, way past a "normal" regrind to make good.
more or less the same casting so not the end of the world BUT... Walter P chrysler would be upset

mains
2.810 for 360
2.500 for 318

ideally you'd just buy a 360 or fit a 318 stroker crank (universally accepted sensible step forward)

BUT in a situation where you had a 318 block and you had a 360 crank and heads (all things that are cast off buy people who want to go faster) you can build a 350 motor where the pistons stick right out the top of the bore..but not so far as to cause top ring problems
but likely to put you in the 11:1 - 12.5:1 static CR position, depends how tall your pistons are
meaning very close attention to dynamic compression ratio will be needed when you choose the cam so you don't make a big pinging pinger
E5 fuel and a good ignition system necessary.

you use the 360 heads because you get bigger valves better flow and the chamber is huge in comparison to the 318 so the pistons do not hit the head

its the kind of thing you would do if there was no aftermarket parts and you didn't live in the country of origin for the motor....

you do it because you want to and everyone says its a bad idea because there are more sensible ways these days to achieve your aims

its on a Par with say

building a 4 inch bore POLY 318
a performance 273
an aussie hemi 6 :)
a turbo FI slant 6

i.e you do it because its what you have and the idea of buying a different engine to throw much of it away apart from the block doesn't appeal.

you'd end up with a piston to deck configuration similar to the aussie RT Hemi 6 and some 340 motors where the piston surface is level or just proud of the gasket surface...

mine stick up further, that was n't the intention but i had to work with what i had. I had to cut the perimeter of the pistons and make sure the little dome edge was nicely smoothed....works fine but moves you away from the universally accepted way of doing it right...

expensive disaster or genius.... hard to tell until you try

keep in mind its easy to build a standard 318 with the pistons level with the deck, buy the wrong cam and make a detonating pinging mess. some thought to cam choice, in respect to overlap and duration when static CR is established, is very necessary
work out your current deck height before you take it all apart. how far different from the deck is the piston crown at top of stroke. you know all the rest. standard piston pin centre to top, standard rod length + stroke add them together with the + or - value you get between piston top and deck and you have deck height

you will need it regardless of what you build


Dave
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

Thanks Neil and Dave
Like I said

IF? :-k
I was to build a 318 with a bit more oomph !! ;)
I will copy all the input and information

Again thank you all :thumbright:
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TIB3300
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Re: 318 upgrade ?

Post by TIB3300 »

Just like to thank you again and the Mopar Muscle Association UK


I know I don't come on here too much and I don't even have a MOPAR, but I seem to get help and information from you guys :thumbright:

Hope you all have a great summer and you never know? I may meet some of you guys ?
Tony B
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