340 build .30 over

[19scamp72]

Hey guys im wodering what ya think of my first build
1972 scamp
1969 340 block
X heads
.30 keith black pistons 10:5:1
Comp thumpr cam kit
Specs
Intake at.50 227
Exh 241
With factory valve train
486 lift intake
473 exhaust
Pro comp 1.6 roller rockers
High pressure oil pump
Doug headers TTI exhaust
Mopar perforamce intake with channel cut out
4150 holley 750 cfm

Trans

727
2800 stall
323 gears
Sure grip posi
Reverse manual valve body

What will i roughly make hp wise and qm, getting excited for my first mopar build

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[moparlover]

beautiful!

 

[19scamp72]

beautiful!

Thanks lets have some.guestimates on hp anyone?

 

[Kevin D.]

Whats the story on 3 and 4 throw on the crank? Just wondering,Kevin.

 

[19scamp72]

Thats factory casting! I thought it was welds... but machine shop said its how it was casted from.factory

 

[K.O. SWINGER]

I think its nice match of parts and will run great but with your cam and the short stroke of the 340 A 355 to 410 rear gear would make it shine ...345 rock you will love it!

 

[GEO]

Looks like a similar build I had in my dart before the current one , If I remember right dest top dyno had it at about 390hp and 420 fl. lbs of torgue

 

[K.O. SWINGER]

390 is a very good guess

 

[swinger340]

Ill guess 375ish HP (possibly closer to 400 depending on head work) . Looks like a sweet combo. Not sure what you had before, but that will definitely put a smile on your face. I have always liked the quick revving little 340s.

 

[19scamp72]

Had a 318 all bone stock i bought the car never drove it with 318.. started my 340 build right away! Cant wait for for spring! Im hoping at least 375 hp... prob going with a 391 gear one day.
Like i said my first mopar my father who recently passed away always loved his mopars i sold my 1966 beaumont and put a mopar in his garage. Hehe he will be cruising with me hanging on my rear veiw! He always swore by his 340s i guess ill find out why!

 

[K.O. SWINGER]

Had a 318 all bone stock i bought the car never drove it with 318.. started my 340 build right away! Cant wait for for spring! Im hoping at least 375 hp... prob going with a 391 gear one day.
Like i said my first mopar my father who recently passed away always loved his mopars i sold my 1966 beaumont and put a mopar in his garage. Hehe he will be cruising with me hanging on my rear veiw! He always swore by his 340s i guess ill find out why!

very cool!

 

[NC Engine Builder]

Nice build, but is that compression a actuall measured ratio, or a "advertised" ratio based on the pistons? a true 10.5 with open chamber X heads is gonna be on the verge of detonation with this crap they call gasoline these days.

 

[RustyRatRod]

377 HP @ 5500 and 382 LB FT @ 4500.

 

[EL5DEMON340]

If those are the cheap pro comp Chinese rockers your going to be on here in a few months asking why the rocker seized. Go with the stock stamped rockers!!

 

[19scamp72]

Nice build, but is that compression a actuall measured ratio, or a "advertised" ratio based on the pistons? a true 10.5 with open chamber X heads is gonna be on the verge of detonation with this crap they call gasoline these days.

I cant recall 100 percent on the conpression it may be 10:2:1 almost sure thats what they said stock is 10:5

 

[19scamp72]

377 HP @ 5500 and 382 LB FT @ 4500.

Thanks rusty, should be fun to drive!

 

[NC Engine Builder]

I cant recall 100 percent on the conpression it may be 10:2:1 almost sure thats what they said stock is 10:5

Find out before you put the heads on, or you will be back later on wanting to know how to fix your detonation problems........ and on a related note, if you have to retard your timing to prevent detonation, you will be losing power and throttle response.....

 

[19scamp72]

The guy who told me exactly what to buy has build lots Of 340s im not to worried. Thanks for the input.

 

[mopar410]

I have a similar setup except I have 650 hp I beam scat rods and a little different cam.Anyway I have stock 1.88 valve heads and my calculations come out to be 10.1ish:1.worst case would be you have to run airplane fuel or an equivalent.

 

[19scamp72]

Hope not!

 

[EL5DEMON340]

The guy who told me exactly what to buy has build lots Of 340s im not to worried. Thanks for the input.

He told you to buy pro comp rockers?

 

[swinger340]

Hope not!

You will be fine. I have a 10.2:1 J headed 340 w mp .284/.484 cam runs just fine on 89-91

 

[19scamp72]

He told you to buy pro comp rockers?

Got them cheap... and they work better for spring clearance other rockers that were more expensive wouldnt clear my springs.

 

[RustyRatRod]

Don't run aviation fuel. It has additives to deal with altitude that will ruin an automotive engine.

 

[19scamp72]

No if i need race fuel, i can get proper fuel off my brother, might do a track run with advanced timing and race fuel one or 2 times for fun.