Street 383 recommendations

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TristanCuda67

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I have a 70 383 block factory pistons and 346 heads, was planning to put the small thumpr cam in it, and run an Edelbrock performer intake on top. This is going in my 67 barracuda fastback and was hoping to get some performance gains out of it but nothing crazy. Would this setup suffice to that and be streetable?
 
Yes but I’d run the RPM & ether bowl port the head or look at a set of new cylinder heads. The cylinder head can benefit from a little work. Valve job/bowl work. After that, an aluminum head may prove to be better and cheaper.

You didn’t mention what size Thumper. Just the small one.
The Edelbrock Performer is equal to the factory manifold.
The RPM fits under the hood. Use a Mancini Racing drop base air cleaner.
 
Summit 6401 cam and lifter kit and Edelbrock RPM or Holley Street dominator with a Holley 3310.
 
fishmens67 said:
That magic cam always worked well in a stock 383.
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I think it's the dead best street grind ever and that Summit cam is basically it. Almost makes me wanna find a 383. LOL
 
rumblefish360 said:
Yes but I’d run the RPM & ether bowl port the head or look at a set of new cylinder heads. The cylinder head can benefit from a little work. Valve job/bowl work. After that, an aluminum head may prove to be better and cheaper.

You didn’t mention what size Thumper. Just the small one.
The Edelbrock Performer is equal to the factory manifold.
The RPM fits under the hood. Use a Mancini Racing drop base air filter
Click to expand...

rumblefish360 said:
Yes but I’d run the RPM & ether bowl port the head or look at a set of new cylinder heads. The cylinder head can benefit from a little work. Valve job/bowl work. After that, an aluminum head may prove to be better and cheaper.

You didn’t mention what size Thumper. Just the small one.
The Edelbrock Performer is equal to the factory manifold.
The RPM fits under the hood. Use a Mancini Racing drop base air cleaner.
Click to expand...
The 227/241 thumpr cam is what I was thinking about
 
Yep if you’re going to use the stock heads do the bowl work and open them up under the valve follow up with a little port matching also.
Free hp!
 
I would run that summit cam long before any thumpr. But if sound is all you're looking for.....
 
RustyRatRod said:
I would run that summit cam long before any thumpr. But if sound is all you're looking for.....
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interesting that the summit cam and that thumpr are almost mirror image on specs. i'd love to see a back to back dyno on them.

anyway this is all a moot point. everybody knows 3/4 race cam is the correct answer here.
 
junkyardhero said:
interesting that the summit cam and that thumpr are almost mirror image on specs. i'd love to see a back to back dyno on them.

anyway this is all a moot point. everybody knows 3/4 race cam is the correct answer here.
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Dang right. lol
 
Isn't the biggest draw back on a 383, the pistons are way down in the hole?
 
TristanCuda67 said:
Yes, but hydraulic roller
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Did you guys miss this.:)

I believe the 346 heads came into existance for the 71' model year with a high 70's chamber and moved to a high 80's for 72/73. Not knowing where the compression ratio ends up, i'd look to stay mild on duration and whatever shelf HR's are available there should be plenty of lift. And no, i don't think a thumper is appropriate for this engine. jmo
 
Carnut68 said:
Isn't the biggest draw back on a 383, the pistons are way down in the hole?
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Not with the 383HP engines. They are close to zero deck height. Speed Pro still makes a forged 383HP piston, too.
 
Here's a bunch of 383 articles

273 said:
Indy EZ-1 Cylinder Heads and Mod Man Intake - Popular Hot Rodding Magazine

Stage VI Manifold Casting - Mopar Muscle Magazine

https://www.hotrod.com/articles/mopp-0210-porting-383-440-aluminum-replacement-heads/

Edelbrock Aluminum Big-Block Mopar Heads - Mopar Muscle Magazine

Dyno a 7.5:1 400? Sure, why not?

Engine Masters Ep. 3 Duels a Mopar 383 vs. Chevrolet 383 – Which Churns More Horsepower?

https://www.hotrod.com/articles/mopp-1205-383-big-block-engine-build/

The Mopar 383 - Engine Buildup - Hot Rod Magazine

Street/Strip 383 Mopar Big Block Build-up

The Story Behind Roadkill’s Crop 1970 Plymouth Duster 383

Chrysler 383 Engine Buildup From The Bottom Up - Mopar Muscle Magazine

Upgrading The 383 Magnum AVS Carb - Mopar Muscle Magazine

https://www.hotrod.com/articles/mopp-0209-383-engine-restore/

https://www.hotrod.com/articles/mopp-0112-rebuilt-resto-stock-383/

https://www.hotrod.com/articles/mopp-0009-how-to-build-a-blueprint-bottom-end/

https://www.hotrod.com/articles/mopp-0010-how-to-install-cams-heads-and-induction/
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I ran a 383 with that thumper cam, Performer RPM, and an 850 Holley dp, and it would snap your neck at go and pull like a sob.

It didn't sound any different to me.

I wouldn't be against swapping it out for that Summit cam, but with all the new cam/lifter horror stories out there lately, don't really want to roll the dice and fix something that isn't broke.

Got another 383 that I bought fully rebuilt with a Mopar 'purple' cam.

Is that a specific cam, or are there versions of it?
 
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