318 upgrades
#120320
09/13/08 08:43 PM
09/13/08 08:43 PM
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Joined: Aug 2005
Posts: 132 Windsor, Ontario
project74
OP
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OP
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Joined: Aug 2005
Posts: 132
Windsor, Ontario
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Hi fellas. Time to upgrade a few things on the boat, ('70 Fury), and I just have a couple of quick ?'s. (Please hold the "build a 360" thing. With gas almost $6 a gallon here I'd like to be able to drive it The combo so far: -Bone stock 318. Comp ratio about 8.8:1 -Edelbrock LD4B intake -Fully rebuilt '88 302 casting heads,(unported), built to stock specs. Got a great deal on these and couldn't turn them down. Figure compression could boost to 9:1 and they gotta be better than the stock 675's on there now. -Carter AVS from a '70 383 A/T. Flow about 635 cfm. Now...how much lift can a new, stock '88 valve spring take? Keep it under .450 and I'll be ok? Also looking for cam recommendations. Thinking maybe a Comp 260H. Stock 904 trans and a 2.76 rear gear. Looking just to give it a bit more punch. The big block plans will have to hold till I win the lottery Thanks and awaiting your wisdom...
1970 Fury III, 318, 4 dr hardtop, aka "The Fridge"
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Re: 318 upgrades
[Re: project74]
#120321
09/13/08 09:34 PM
09/13/08 09:34 PM
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Joined: Sep 2004
Posts: 6,906 IL, Aurora
ademon
master
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master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
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keep the cam under 220@.050 you will have to check the max valve lift, use a 4 hole spacer under the carb to help the low end
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Re: 318 upgrades
[Re: gch]
#120324
09/14/08 12:04 AM
09/14/08 12:04 AM
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Joined: Nov 2003
Posts: 36,040 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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When you do switch heads you might measure your deck height so you can calculate your actual CR for reference but you are in the 7's now.
live every 24 hour block of time like it's your last day on earth
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Re: 318 upgrades
[Re: RapidRobert]
#120325
09/14/08 12:18 AM
09/14/08 12:18 AM
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Joined: Jan 2006
Posts: 3,535 Canuckville
68Cbarge
master
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master
Joined: Jan 2006
Posts: 3,535
Canuckville
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A heavy C with the combo recommended should run at least 3.23's for gears with a 28" tall tire (23570R15). Run 2-1/4" dual exhaust Dynomax Super Turbo muffs for good torque response and fuel economy.If not going with headers,use early Dakota Magnum logs or 360 logs. Recurve the distributor for advance to come in early to move the tank. You can get amazing fuel economy and performance by using a tuned Thermoquad carb. When you switch your heads,roller lifters and rockers can help MPG.So can electric cooling fans.The less parasitic drag,the better MPG. Also it is best to match the convertor to the suggested XE256 cam choice by going one step up in stall speed.
When set up properly with the right engine parts combination,24 MPG highway can be achieved. .
Last edited by 68Cbarge; 09/14/08 12:26 AM.
'68 Newport Custom Barge on a Budget!! BOAB 1973 Satellite WAGON! 318- 3 on the tree!! 2008 Chrysler 300c HEMI!
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Re: 318 upgrades
[Re: 68Cbarge]
#120326
09/14/08 01:53 AM
09/14/08 01:53 AM
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Anonymous
Unregistered
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Anonymous
Unregistered
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302s had HORRIBLE valve springs, a stock cammed 80s 318 floated at 4500-5000 RPM. Definitely invest in some beefed up springs.
Rocker arms too, those are pretty weak. Ask me how I know that.
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Re: 318 upgrades
#120327
09/14/08 02:03 AM
09/14/08 02:03 AM
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Joined: Aug 2005
Posts: 132 Windsor, Ontario
project74
OP
member
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OP
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Joined: Aug 2005
Posts: 132
Windsor, Ontario
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I'll actually be using the rockers and shafts from the '70 heads since they're in such good shape. As for gears, plans are to eventually go with 3.23's Rear is actually an 8.25 and yes it's original, believe it or not. I can't see compression being in the 7's, stock compression listed for a '70 teen is 8.8:1 in every piece of literature I've read. Might be down a bit but that much? Cylinder pressure is really good across the board.
1970 Fury III, 318, 4 dr hardtop, aka "The Fridge"
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Re: 318 upgrades
[Re: project74]
#120328
09/14/08 02:10 AM
09/14/08 02:10 AM
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Joined: Nov 2003
Posts: 36,040 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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I was thinking advertised was 8.2 or 8.4. At 8.8 I would agree.
live every 24 hour block of time like it's your last day on earth
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Re: 318 upgrades
#120330
09/14/08 06:12 PM
09/14/08 06:12 PM
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Joined: Jan 2005
Posts: 4,406 Michigan
MarkZ
Worthy
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Worthy
Joined: Jan 2005
Posts: 4,406
Michigan
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I know you stated to hold the 360 comments, but... In something as heavy as that Fury a motor with a little more displacement and power might actually yield the same mileage, if not better due to the fact it doesn't need to work as hard.
1987 Fifth Avenue - 512/518/D60
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Re: 318 upgrades
[Re: scratchnfotraction]
#120333
09/15/08 09:20 PM
09/15/08 09:20 PM
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Joined: Jan 2003
Posts: 16,123 Grand Haven, MI
patrick
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
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a big car like that I'd use a voodoo 60400 or com XE250, with comp 901 valve springs and stock locks/retainers.
1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!*** 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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Re: 318 upgrades
[Re: patrick]
#120334
09/16/08 01:50 AM
09/16/08 01:50 AM
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Joined: Aug 2005
Posts: 132 Windsor, Ontario
project74
OP
member
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OP
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Joined: Aug 2005
Posts: 132
Windsor, Ontario
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Yeah, I'm starting to look more at the torque heavy cams. This thing will almost never see 5000 rpm so great bottom and good mid is what I'm after. I can dig the whole 360 argument, hell I've even got one in the garage. Couple of the things that made up my mind though was the cost of a full rebuild for the 360 (which it needs) and that by the time I get the cam I'll be about $500 bucks in for the entire 4 brl/heads/cam thing which is what I can afford for the foreseeable future. As for turbos, superchargers and things...for that coin I'd just go BB
1970 Fury III, 318, 4 dr hardtop, aka "The Fridge"
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