Re: Big Block 383 Rebuild questions
[Re: cudaman1969]
#2155080
09/15/16 01:48 PM
09/15/16 01:48 PM
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Joined: Jan 2003
Posts: 75,125 A Banana Republic near you.
JohnRR
I Win
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I Win
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A Banana Republic near you.
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How good is the gas in Germany? 906 heads are fine, tons of race engines used these heads and did fine. Don't go over board on the cam, takes away drivability. Most here on Moparts will have you building a $50,000 race engine to putt around on the street. Keep it simple, you'll be fine with what you got. Good luck on your endeavor. Let us know how it works out. Mike Yes 906 heads are fine, but not with a piston that is speced to be used with a 516 sized/shape combustion chamber. Tons of race engines USED them because they were all they had to use, or the class specified them, otherwise they are a POOR choice, especially in a 383 that is hard to build compression in to begin with. I just did the math, 90cc head, .041 gasket that is in the kit he bought, a piston .087 in the hole on a blueprint block (1.848 ch), his block may be a little taller, 7.52 compression ...
running up my post count some more .
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Re: Big Block 383 Rebuild questions
[Re: JohnRR]
#2155138
09/15/16 03:19 PM
09/15/16 03:19 PM
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Joined: Jan 2004
Posts: 8,374 fredericksburg,va
cudaman1969
master
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master
Joined: Jan 2004
Posts: 8,374
fredericksburg,va
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How good is the gas in Germany? 906 heads are fine, tons of race engines used these heads and did fine. Don't go over board on the cam, takes away drivability. Most here on Moparts will have you building a $50,000 race engine to putt around on the street. Keep it simple, you'll be fine with what you got. Good luck on your endeavor. Let us know how it works out. Mike Yes 906 heads are fine, but not with a piston that is speced to be used with a 516 sized/shape combustion chamber. Tons of race engines USED them because they were all they had to use, or the class specified them, otherwise they are a POOR choice, especially in a 383 that is hard to build compression in to begin with. I just did the math, 90cc head, .041 gasket that is in the kit he bought, a piston .087 in the hole on a blueprint block (1.848 ch), his block may be a little taller, 7.52 compression ... He's got a 383 not a multi dollar blown Hemi. What he's got will make a good street engine for the money he's ALREADY spent. What ever we spend for the good heads here in the states, double that for him over there.
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Re: Big Block 383 Rebuild questions
[Re: FelixM1992]
#2155143
09/15/16 03:37 PM
09/15/16 03:37 PM
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Joined: Jan 2003
Posts: 75,125 A Banana Republic near you.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,125
A Banana Republic near you.
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I'm not saying he needs to spend millons on a head, it is what it is.
Are you ASSuMEing he has a super duper PORTED head off someones race engine? In stock form a 383, in a car weighing almost 4000 lbs, overcammed is going to be less than impressive, especially with 7.5 compression...
Hopefully joining that group SuperRob mentions will garner him some help , hopefully parts wise and finding a capable shop that can build that engine right.
running up my post count some more .
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Re: Big Block 383 Rebuild questions
[Re: FelixM1992]
#2155294
09/15/16 08:15 PM
09/15/16 08:15 PM
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Joined: Jan 2003
Posts: 20,968 A collage of whims
topside
Too Many Posts
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Too Many Posts
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Posts: 20,968
A collage of whims
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For a street 383 in a fairly heavy car, been there & done that, and here's what I'm thinking given what Felix has told us so far: You can either return the piston kit and get one with more compression from the same source, or look at 440source.com and see what they have. A cast piston will be fine but forged holds up better to detonation. Not knowing the octane ratings in the Fatherland, I wouldn't want to go more than 9.0:1 on an iron-head Wedge @ 91-92 octane. The Edelbrock cam is kinda short on lift, but IF you also need rocker arms, a 1.6 ratio would help that. Otherwise, look at more modern stuff like the various Comp Cams, Engle choices. Something in the 214-224 @ .050 and around .450-.480 lift will be mild enough for a stock converter at 9.0:1 CR. I've used as much as .504 lift at that duration with tall gears & stock converter and had very nice street manners. With old stock heads & block, a surface cut is likely needed for flat decks on both. Good machine work, balancing, and a good valve job go a long way; find a GOOD machine shop that's familiar with American engines and has an eye for details. There's maybe .5 CR there without going nuts. I like double springs on the valvetrain, and at least a windage tray. Use a dual-plane intake (look in the ads here for nice used), and a 650CFM carb would be adequate. The Eddy & Stealth heads I've used all needed a better valve job, and the springs & parts were OK.
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Re: Big Block 383 Rebuild questions
[Re: topside]
#2155607
09/16/16 11:18 AM
09/16/16 11:18 AM
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Joined: Dec 2005
Posts: 178 Hamburg - Germany
SuperRob
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member
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Hamburg - Germany
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Not knowing the octane ratings in the Fatherland, I wouldn't want to go more than 9.0:1 on an iron-head Wedge @ 91-92 octane. Gas stations max out at 95 octane (called ultimate102 over here).
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Re: Big Block 383 Rebuild questions
[Re: SuperRob]
#2155645
09/16/16 12:09 PM
09/16/16 12:09 PM
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Joined: Jan 2003
Posts: 75,125 A Banana Republic near you.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,125
A Banana Republic near you.
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Not knowing the octane ratings in the Fatherland, I wouldn't want to go more than 9.0:1 on an iron-head Wedge @ 91-92 octane. Gas stations max out at 95 octane (called ultimate102 over here). If he could find even a set of 516 heads over there those with a little porting and 1.74 valves that would be better than the 906's , but he would need to get a piston that is closer to zero. DO NOT HACK .087 off the deck to get those pistons at zero , it would be cheaper to just buy another set of pistons from summit and have them shipped over. Which wouldn't be a bad idea,in the long run that will save him money.
running up my post count some more .
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Re: Big Block 383 Rebuild questions
[Re: FelixM1992]
#2155688
09/16/16 01:29 PM
09/16/16 01:29 PM
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Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
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Posts: 36,041
Lincoln Nebraska
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i dont want a race engine i want a little more than the original engine was. I would go with a dual plane intake & a fairly small carb possibly one of the newer ones that all the metering systems are adjustable. Holler what parts you go with & how it turns out (if it meets your expectations)
live every 24 hour block of time like it's your last day on earth
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Re: Big Block 383 Rebuild questions
[Re: FelixM1992]
#2155742
09/16/16 02:29 PM
09/16/16 02:29 PM
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Joined: Jan 2003
Posts: 4,292 Morrow, OH
markz528
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Morrow, OH
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I just went through this on my 67 383. I bought KB pistons and on paper I was to be at 9.0:1 compression. Measured came in at 8.2:1 and I cried.
I fortunately was able to recover by milling the 915 heads 0.040 inches and that got me to around 8.9:1 (from what I recall - could be a tad less). But that was with a closed chamber head - the open 906 head puts you in a much worse position.
67 Coronet 500 9.610 @ 139.20 mph 67 Coronet 500 (street car) 14.82 @ 94 mph 69 GTX (clone) - build in progress......
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Re: Big Block 383 Rebuild questions
[Re: FelixM1992]
#2157547
09/19/16 05:07 PM
09/19/16 05:07 PM
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Joined: Aug 2013
Posts: 43 League City, TX
BlueGhost
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Posts: 43
League City, TX
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If you haven't rebuilt your heads yet, you might consider the Edelbrock E-Street heads. The 75cc e-streets, part # 5090, are around $1300, available trough Summit, and would bring compression up to 8.5:1.
1958 Plymouth Suburban
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