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Old 02-16-2014, 06:51 PM   #1
Unca
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engine work and theory crafting

Ok im looking at doing some engine work. atm 454, 850 holly dbl pumper, mechanical secondarys (worked over some...), aluminum intake, hei ignition, tri- y- headers, the cam chains a touch stretched, a few oil leaks and some general annoyance with the looks of things overall... im thinking new cam, rockers, freshen up the rings n bearing, look the heads over do some tweaking if needs be. so. the question....

what cam? think cruiser / toy.. some light to light play.. perhaps dust of a mustang or two... I don't mind a lopy idle but don't want a eternal headache should I decided to take her on a road trip of a couple hundred miles...
chain? or gear drive? .. I like a lil noise but they rob performance.
of course new rings n bearings, new oil pump. gaskets, freeze plugs n such.
upsize the carb some?... I REALLY miss my tune port tbh... carbs are fine but I did enjoy the tpi.
do I do away with the engine fan? go electric fan?
should a guy just go ahead n throw a 496 stroker in it?
forged... just in case..
I know atm I cant hook up the hp / torque ive got but as she grows I think a 4 link n coil overs, Detroit locker.... think heavy footed fun and a desire to smile now n then.
so.. input? thoughts? ideas?
I know budget... ugh. I could freshen her up, throw her back in say for a grand or so. cam n flat tappets.. minimum goodies..
a stroker adds another 1200 or so to it... machine shop$$$$????? im not sure on that one.. anyone have a general idea?

so... lets burn some time on a relaxing sunday evening n help me make a plan n spend some of my tax check...
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Old 02-16-2014, 10:21 PM   #2
68Timber
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Re: engine work and theory crafting

What cam is in it now?
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Old 02-16-2014, 11:18 PM   #3
Unca
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Re: engine work and theory crafting

small... aka too mild im not certain but id almost guess a "rv" cam mild idle smooth... bleh
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Old 02-17-2014, 12:21 AM   #4
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Re: engine work and theory crafting

I've heard good things about the Comp 268 in a mild 454. Do you know what compression ratio it's at?
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Old 02-17-2014, 08:17 AM   #5
Unca
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Re: engine work and theory crafting

Id guess low compressionit runs ok, itll smoke the tires quite nicely. but its no beast by any means, the block casting numbers show its a 73, heads are rectangular port. I looked at the 268 grind myself. the card and such seemed reasonable. anyone have personal experience? head work required? new springs? roller retrofit? flat tappet?
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Old 02-17-2014, 12:40 PM   #6
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Re: engine work and theory crafting

A friend of mine put a 268 in a coworkers 74 with a 454 a long time ago while doing a stock rebuild. I know they were real happy with it.
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Old 02-17-2014, 02:17 PM   #7
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Re: engine work and theory crafting

I would think the 850 double pumper would be fine.

I run one on my 1000 hp 555 cu in big block when I run the Nostalgia Classes. I run a Dominator in the "Open Comp" type classes.

As far as cylinder heads - the rectangular port heads should be plenty. Just clean 'em up and freshen: valve job, new seals, etc.

K
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Old 02-22-2014, 09:48 AM   #8
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Re: engine work and theory crafting

ok doing more research. looking at the following grinds...
the engine as it sits.

454 eldelbrock performer 2.0 intake. holley 850 dbl. pumper. headers.. 2.5 inch dual exhaust out the back. turbo 400 trans. 12 bolt rear.. i'm unsure of the gearing. id vote lowish like 3:42 / 3:55 ish...

a sunny day cruiser.. cruise nights a now n then couple hundred mile weekend trip some light to light fun in the sun beating down the local mustang crowd.. a smile for me to enjoy when I feel like burning up 50 bucks worth of tire...

xe268h "a street machine grind"

x4 270h "4 x 4 cam"

270h which sounds to me a little hotter / higher rpm performance cam.

im not anti a low rpm converter.. say 1500-2500 its not going to tow much if anything at all.. ( maybe my small family boat... 3500 pounds to the local lake...)
so lets hear some input, opinions... thoughts? experiences.... lay it on me.
the missus said I could have the cash for my goodies.. so lets build this.
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Old 02-23-2014, 10:41 AM   #9
Unca
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Re: engine work and theory crafting

I pulled the engine yesterday, got casting numbers and looked this over some. I have not disassembled it yet so no exact measurements as of yet. but the info I have is as follows.
block casting numbers.
K1 72
GM 101
conv
3999289
T110Trl
Hi per Pass F 8

in reading off the web. it seems its a decent block supposedly a good series as far as machined accurately.... any input or thoughts?

the heads..
14081045...
translation a "045" head?
open chambered 119 cc ...ish?
has the truck valves.. smaller?
input? thoughts ideas?
ill be tearing the engine down this afternoon so I guess its time to consider the mods or replacement of any issues known or found. so bbc guru's.. lay your knowledge upon me.
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Old 03-10-2014, 07:41 PM   #10
68Timber
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Re: engine work and theory crafting

What did you decide to do with it?
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Old 03-10-2014, 08:43 PM   #11
Unca
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Re: engine work and theory crafting

a bottom end rebuild, new pistons rings bearings, head work, 270h cam. a overall freshening up n some attitude...
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