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Old 10-09-2001, 11:04 PM
meepmeep426 meepmeep426 is offline
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Default Building a big block- Ideas please

Im building a motor (383) for a '70 Fury 1 and want good all around performance.It will be used for daily use and occasional towing...Its a 30 over block with 10 to 1 pistons,Ive got 906 heads,factory HP cast exhaust manifolds,MP distributer and chrome box,and I have an early model edelbrock torker intake, and I have a stock Holley 4 BBL carb with vacume secondaries that came on early 70's big blocks. Tranny is a 727,2400 stall,and gears are 323 in rear. What cams should I consider and would this intake work,or should I use another type,as well as another carb choice.What has worked for you guys?
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Old 10-10-2001, 02:50 AM
Walkercolt Walkercolt is offline
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You want to tow what? With 10:1 pistons it'll knock itself to pieces except on 108-112 race gas. That's what old Gulf "No-Nox"was rated at. What you need for towing(I've got a small RV trailer behind a 5.2(318) auto Dakota) is grunt. You may be able to salvage your pistons with Fel-Pro thick head gaskets, they should give you a reasonable CR.You want a short duration no overlap "torquer cam", or an RV cam.With your high stall TC, you'll need a honking big trans. cooler. You also need a 3.55 rear end minimum if you want to tow anything above 5000lbs., and a good frame mount drawbar, and Eaz-Lift weight distributing hitch. Your current carb is as large as you'd want for towing, a bigger carb will be "mushy" on the bottom(not enough intake signal). I don't know how long the runners are on you intake, but for towing , the longer the better. Get that 14"x3" K&N air filter so you can get the air into the motor. Comp Cams, Hughes Engines, shoot any good cam place can give you specfic reccomendations, and you can always advance the cam a little for more low-end. Good Luck.
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Old 10-10-2001, 08:35 AM
meepmeep426 meepmeep426 is offline
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The camper is near 4000 lbs. and the boat I have in mind is about 3500....plus my kids cars ALWAYS need a tow...which all have tow tabs now,for conveinence sake.The intake should be a dual plane,with long runners,correct?Know of any one in perticular?AS for the compression,my stock 66 383 had 10 to 1 comp,and only pinged slightly on less than 91 octane...so I thought that 93 should be sufficiant.With my expirence,an RV cam runs out of breath low on the rpm scale,and I was hoping that theres one out there that someones used with a little more grunt.Oh,and I do have a big honkin trans cooler,but the stall converter was thrown into the equasion for Q & A,as I do have a stock converter to use.The hitch is a class 3,and weighes as much as my daughters car!
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Old 10-10-2001, 08:52 AM
Dr. Righteous Dr. Righteous is offline
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Default Intake, lower comp, short cam.....

The only thing I would add is forget about the single plane intake and go in favor of a stocker spread bore or a Edelbrock Performer or the like. IF, you can get ahold of a good ThermoQuad carb that is an ideal towing (or heavy) vehicle carb. It has a "midrange" step on the metering rods that helps with pulling. A 383 is a short stroke motor (shorter stroke than a 360) and it needs a bit of help on the low end. Also it sounds like you went with KB hypertec pistons in your engine. An excellent choice (that is what is in my 383) but for towing you need much lower compression or make sure your timing and distributor advance curve is in check. A 383 likes a slower advance unless you have tall gears behind it. A stocker cam should be fine for your application or one up with a Crane RV cam.
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Old 10-11-2001, 01:28 AM
Walkercolt Walkercolt is offline
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OK, an RV cam should be all bottom end and no top-end power, that's the whole idea for towing. If you've had any pinging problems, towing will make them a lot worse. You've got a pretty good "base engine", now just make the mods to tow better. I think most any good(modern) dual plane intake would be good.Surprisingly, an old cast iron stocker will work well for towing too. I can't hardly stress enough your rear axle needs a lower(higher numerically) ratio. With the 383, alot of Challengers were purchased with 4.10 Danas, not only for durability, but for the ratio.
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Old 10-11-2001, 10:05 AM
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Glen440 Glen440 is offline
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I think the 3.23 will work good. My friends towed their stock cars with stock 318 cop cars with 2.94-3.23 gears with no probs. The cars were just over 3000 and the trailers are around 1500pounds.
One even used a slant six for a while. I'm sure the 383 with a good RV cam will make more than enough torque.
I drove my 400 Volare to Florida (30 hours one way) and towed a boat back with it. Maybe weighed around 2500-3000 pounds.
I had the .484 cam and 2.94 gears. I never even made it into the cams powerband and the 400 never even knew it was towing anything. It even got the same gas mileage. It was funny cause I put more miles on my car in 2 days than alot get in a whole summer. The high comp may be an issue, and a dual plane intake is a must on a 383-400. I put a Torker intake on my 400 and it killed so much torque it wasn't funny.
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