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Author
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Topic: Destroked Engines?
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69 Sportsroof
Gearhead Posts: 2124
From: Valley, Alabama, USA
Registered: Mar 2002
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posted 01-09-2005 12:21 PM
   
Had a guy ask me if I had heard of folks destroking 351w's down to a 331. Told him nope but you can stroke a 302 to 331. Anyone ever heard of this? What would be the reasoning behind it?
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69 Sportsroof
Gearhead Posts: 2124
From: Valley, Alabama, USA
Registered: Mar 2002
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posted 01-11-2005 12:49 PM
Anybody heard of this or he just some dumb chevy guy?
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SteveLaRiviere
Administrator Posts: 44935
From: Saco, Maine
Registered: May 99
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posted 01-11-2005 01:08 PM
Yes, they do this. Usually to get an engine to get within a certain engine size in classes like Trans Am for example.------------------
'70 Mustang Mach 1 351C 4V/FMX/3.25 Open
'70 Mustang Convertible 250 I6/3 speed/2.79 Open
'72 Mustang Sprint Hardtop 351C 4V/FMX/4.30 Trac Loc
'94 F-150 XL 5.8L/E4OD/3.55 Limited Slip
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Scott (69Mach)
Gearhead Posts: 787
From: Walnut Creek, CA USA
Registered: Jun 99
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posted 01-11-2005 01:09 PM
I know a Chevy guy that did it to his 350. Don't remember why exactly, but he liked the result. Must wind faster...
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indyphil
Gearhead Posts: 2690
From: Senoia, G.A. USA
Registered: Jul 2002
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posted 01-11-2005 01:36 PM
If your going to go crazy with boost it might help keep the crank in one piece (a forged 331 crank will hold on at higher loads and RPMS than a 351 or longer), you get the stronger 351 block, and you can use a really long rod/stroke ratio. Seems like it would only make sense for staying under a Cubic inch limit, or if you were going to make massive boost to compensate for the lost cubic inches and structural limits were your main concern. ------------------
'68 coupe, '66 289 C code
engine, edel 600cfm carb, performer intake, dual exhaust http://www.geocities.com/ottouk_77/68mustang.htm
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lonewolf
Gearhead Posts: 308
From: Colorado; M&M #3117
Registered: Jul 2003
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posted 01-11-2005 02:37 PM
You see this quite a bit here (Colorado). I asked a guy once and he indicated it was the combination of large bore/short stroke/long rod but I can't remember exactly why he said he did it.Cheers, Rick
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Moneymaker
Administrator Posts: 26813
From: Lyons, IL, USA
Registered: May 99
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posted 01-11-2005 03:46 PM
Big bore/short stroke is for high RPM big port head deals.I had a Boss 302 destroker deal in my old Modified Eliminator Mustang.
294 inches and 10k + RPM.  ------------------
Alex Denysenko
Co-Administrator and Moderator NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA & SS/MA National Record Holder '00,'01,'02,'03,& '04
First SS/MA in the TENS!
IHRA division 5 Superstock Champion
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28 The Barry of BarrysGrrl Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"
www.moneymakerracing.com
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Dubz
Gearhead Posts: 1890
From: Manitoba Canada
Registered: Oct 2002
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posted 01-11-2005 04:36 PM
heard of it before, but the only time i've heard of someone doing it was on a twin turbo big block so they could get some more rpms out of it.
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Rustang
Gearhead Posts: 805
From: Clarion PA
Registered: Nov 2000
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posted 01-11-2005 04:40 PM
quote:
Originally posted by Moneymaker:
Big bore/short stroke is for high RPM big port head deals.I had a Boss 302 destroker deal in my old Modified Eliminator Mustang.
294 inches and 10k + RPM.
Alex, do you know Jim Ivanuik? He used to race some stuff like that in Modified Production.
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69 Sportsroof
Gearhead Posts: 2124
From: Valley, Alabama, USA
Registered: Mar 2002
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posted 01-11-2005 08:54 PM
Oh well. Guess you learn something new every day. Thanks!
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Moneymaker
Administrator Posts: 26813
From: Lyons, IL, USA
Registered: May 99
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posted 01-11-2005 09:19 PM
The name sounds somewhat familiar.------------------
Alex Denysenko
Co-Administrator and Moderator NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA & SS/MA National Record Holder '00,'01,'02,'03,& '04
First SS/MA in the TENS!
IHRA division 5 Superstock Champion
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28 The Barry of BarrysGrrl Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"
www.moneymakerracing.com
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Rustang
Gearhead Posts: 805
From: Clarion PA
Registered: Nov 2000
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posted 01-12-2005 12:40 PM
Just curious, alex. He's a pretty respected engine builder in the Pittsburgh area and I think he got his start running Cleveland stuff in MP in the seventies. When I can afford it, that's where I usually take my stuff. 
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Rustang
Gearhead Posts: 805
From: Clarion PA
Registered: Nov 2000
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posted 01-12-2005 12:42 PM
Just curious, alex. He's a pretty respected engine builder in the Pittsburgh area and I think he got his start running Cleveland stuff in MP in the seventies. When I can afford it, that's where I usually take my stuff.
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Dusty Kiser
Gearhead Posts: 180
From: Bethel,Oh USA
Registered: Mar 2002
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posted 01-15-2005 10:15 PM
quote:
Originally posted by Moneymaker:
Big bore/short stroke is for high RPM big port head deals.I had a Boss 302 destroker deal in my old Modified Eliminator Mustang.
294 inches and 10k + RPM.
Those little Bosses were bad to the bone. Roush was getting 2.3hp/cu.in. with a destroker. Bob Corn was a Ford engineer who ran a coupe like yours Alex, with two inline autolites on a Cross Boss. His motto was, Build for power and screw torque! If you need torque, gear it! He was pulling a 6.5 gear with 29in tires.
The Chevvy guys went to destrokers because they didn't have enough head to feed a big motor. Ault and James had a 287 in a split window Vette that was strong in the days before the aftermarket heads came out for the Chevs. C.J. Batten welded some heads and they used the big Crower eight port injectors to dominate F/G and local modified eliminator racing.
We built a destroked Boss 429 for a late model stock car that had a cu.in. to weight limit. By running 385 inches we could race 300lb lighter.It pulled like hell from 5000 to 8500rpm. The heavy valve train was hell on parts, though. We broke Crower lifters and Holman Moody valves. Have you ever seen what that danged sodium does to aluminum?
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Moneymaker
Administrator Posts: 26813
From: Lyons, IL, USA
Registered: May 99
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posted 01-15-2005 10:20 PM
Bob Corn was my hero when I was a kid just getting serious abouot this sh*t. ------------------
Alex Denysenko
Co-Administrator and Moderator NHRA/IHRA/SRA member and licensed Superstock driver
NHRA and IHRA SS/LA & SS/MA National Record Holder '00,'01,'02,'03,'04 &'05
First SS/MA in the TENS!
IHRA division 5 Superstock Champion
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28 The Barry of BarrysGrrl Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"
www.moneymakerracing.com
IP: Logged |
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