Building a S̶t̶r̶o̶n̶g̶ ̶3̶5̶0̶ 383 for Frank the Tank…

[JimmyDuncan]

If you have access to Excel, it's a wonderful tool for just this type of situation.
Below is my Excel file for purchasing. The colored rows signify the components
that I wanted the machine shop to buy at that time.

Great. I'll try to fill it all out this weekend.

Maybe it don't matter, but are those heads straight plug or angled. They look
to be straight, but I can't tell for sure. Will they work with your headers?

If possible I would try to get the 7/16 inch studs in those heads or have you
already bought your rocker arms?

Yes, straight plug.... I am still trying to source headers locally... So, the headers will be made to fit the heads....

They don't appear to do 7/16 studs.... Is that worth doing after the fact? I haven't got rocker arms yet..

 

[JimmyDuncan]

I found some flow data on those heads:
Intake = .100 - 65, .200 - 137, .300 - 189, .400 - 224, .500 - 235, .600 - 234.
Exhaust = .100 - 62, .200 - 104, .300 - 140, .400 -160, .500 - 170, .600 - 174.

I would definitely do some port matching and bowl clean up and you'll flow a little bit more.
I was playing with DD2000 and that crane solid cam would do pretty good with those heads!

Great! Thanks. I think port matching and bowl clean up will be within my capabilities... I'll give it a go.. After I read up on how to..

Guesstimation of 401 hp @ 6000 and 415 tq @ 4500 with the crane solid. Pretty strong tq to be pulling Frank the Tank! You could gain about 3-4 hp if you retard it to 75lvc, but you would lose about 9 in tq. I ran it at 71 lvc for the 401hp/415tq.

That's not bad..... I was expecting a little more... But, that was before the budget got reined in I guess.... Nothing to sneeze at..

 

[busterrm]

I know your limited on budget but a roller would give some more power increases. You could run the CompCams Magnum 280 roller with 1.5 rockers with 2v pistons, retard the cam 4 degrees, gasket match the ports/clean up bowls and have about 450hp @ 5500 and 460tq at 4000. I am running that cam in my engine, but mine I had Compcams put it on a billeted core and I am running 1.6 rockers. I am running RHS 200cc heads and I will be around 500hp @ 6000 and lil above 500 tq @ 4500. I think you can get that cam on a regular core for about 285 - 300 bux US.

 

[87vette81big]

Before You Get All Hellbent On High Flow Cylinder Heads & Roller Cams You Need to Decide What You are Doing for Exhaust Jimmy.
I Think You Are Limited on Header Options for Frank The Tank.
You May Need to Use Factory Small Block Chevy Ram Horns.
Or Corvette SBC Ramhorn Exhaust Manifolds.

I have to use Exhaust manifolds on my Olds 425 V8 in my 1963 GP.

To pay somebody to build Custom headers that work costs $2,000-5,000 cash.
To buy The TIG Welder to build your own Headers costs $2,000-5,000 cash Too.

REALITY CAN SUCK ASS.
$

Least thought of is Headers to fit all applications.

Chevy Ram Horns Ok.
Olds 425 Exhaust manifolds I got coming Ok Very Good Too.

 

[87vette81big]

When limited to Exhaust manifolds spending a lot of $ on Top End is ????

 

[Indycars]

They don't appear to do 7/16 studs.... Is that worth doing after the fact? I haven't got rocker arms yet.

It's not a "have to thing", but it would reduce the flexing considerably of the stud
during valve lift. You also could get a stud girdle for your 3/8 studs. The ARP studs
run between $45 and $100. It say that it needs machine work, but I bet that's
because OEM use pressed in studs. You would need to talk with ARP to know for
sure which PN and and machine work needed.

If you order from the manufacture, they could no doubt could put 7/16 inch studs in
for little additional cost. Or ask JEGs about supplying them with 7/16 inch studs.

http://www.summitracing.com/parts/arp-200-7202/overview/
http://www.summitracing.com/parts/arp-135-7102/overview/

 

[Grumpy]

while swapping from 3/8" to the larger 7/16" rocker studs makes sense,
its rather easy in many cases to skip that machine work and still greatly increase valve train rigidity.
with a rocker stud girdle and longer reach rocker nuts (just one option)

but with the mild cam used I suspect NEITHER options needed

http://www.summitracing.com/parts/pro-66950

http://www.summitracing.com/parts/sum-141010

 

[JimmyDuncan]

Before You Get All Hellbent On High Flow Cylinder Heads & Roller Cams You Need to Decide What You are Doing for Exhaust Jimmy.
I Think You Are Limited on Header Options for Frank The Tank.
You May Need to Use Factory Small Block Chevy Ram Horns.
Or Corvette SBC Ramhorn Exhaust Manifolds.

I have to use Exhaust manifolds on my Olds 425 V8 in my 1963 GP.

To pay somebody to build Custom headers that work costs $2,000-5,000 cash.
To buy The TIG Welder to build your own Headers costs $2,000-5,000 cash Too.

REALITY CAN SUCK ASS.
$

Least thought of is Headers to fit all applications.

Chevy Ram Horns Ok.
Olds 425 Exhaust manifolds I got coming Ok Very Good Too.

I'm seeing a few options from Hooker headers on ebay here in Oz Brian. So, there will be options.. I just need to find a good value set that are suitable...

 

[JimmyDuncan]

It's not a "have to thing", but it would reduce the flexing considerably of the stud
during valve lift. You also could get a stud girdle for your 3/8 studs. The ARP studs
run between $45 and $100. It say that it needs machine work, but I bet that's
because OEM use pressed in studs. You would need to talk with ARP to know for
sure which PN and and machine work needed.

If you order from the manufacture, they could no doubt could put 7/16 inch studs in
for little additional cost. Or ask JEGs about supplying them with 7/16 inch studs.

http://www.summitracing.com/parts/arp-200-7202/overview/
http://www.summitracing.com/parts/arp-135-7102/overview/

View attachment 7010

I'll do a bit more research.. Thanks Rick. But, as Grumpy mentions, maybe a rocker stud girdle, or potentially nothing will be required for my mild build..

 

[JimmyDuncan]

while swapping from 3/8" to the larger 7/16" rocker studs makes sense,
its rather easy in many cases to skip that machine work and still greatly increase valve train rigidity.
with a rocker stud girdle and longer reach rocker nuts (just one option)

but with the mild cam used I suspect NEITHER options needed

http://www.summitracing.com/parts/pro-66950

http://www.summitracing.com/parts/sum-141010

In you view Grumpy, what sort of hp or tq output would you say upgraded studs or a girdle be required? Is it something that can be added later if issues become apparent..?

 

[Grumpy]

its not horsepower, its the stress on the valve train, that makes a rocker stud girdle and its increased rigidity useful,
and thats more closely related to average stress levels, RPM and VALVE SPRING LOAD RATES
any time your occasionally exceeding 6000rpm or getting close too 330 lbs of open valve load rate Id strongly suggest screw in rocker studs
any time your intentionally exceeding 6000rpm and exceeding 350 lbs of open valve spring rate a rocker stud girdle might be a good idea.
and if your regularly exceeding 6500rpm and 400 lbs of open valve spring load rate its use is going to become almost mandatory

 

[JimmyDuncan]

its not horsepower, its the stress on the valve train, that makes a rocker stud girdle and its increased rigidity useful,
and thats more closely related to average stress levels, RPM and VALVE SPRING LOAD RATES
any time your occasionally exceeding 6000rpm or getting close too 330 lbs of open valve load rate Id strongly suggest screw in rocker studs
any time your intentionally exceeding 6000rpm and exceeding 350 lbs of open valve spring rate a rocker stud girdle might be a good idea.
and if your regularly exceeding 6500rpm and 400 lbs of open valve spring load rate its use is going to become almost mandatory

Ah yes, makes sense.

I don't anticipate revving the engine that high... often or ever.. With the build I'm working towards, how do I calculate how high the RPM and/or lbs of valve load might be when/if I do a few runs at the drags?

Is it about choosing to limit the revs, or would the engine and drive line setup have a natural limit on what it could get to RPMwise?

 

[Grumpy]

with the parts youve listed I feel rather confident that power will peak and start to fall off at a bit lower than 5800 rpm so while you'll have good useful power in a use-able rpm power band, I think the fact that both the transmissions likely shift points, with most valve body control kits ,and your cams some what limited duration will make it rather obvious that 6000 rpm is most likely the upper limit

 

[87vette81big]

If you run a Flat Tappet Hydraulic camshaft then a Stud Girdle is not really required .
Optional.
Many fit poorly onto cylinder heads other than Brodix.
The studs are not always drilled and tapped inline right angle square.

If you have lots of $$$$ shaft rockers & Rolker cam it.

 

[JimmyDuncan]

If you run a Flat Tappet Hydraulic camshaft then a Stud Girdle is not really required .
Optional.
Many fit poorly onto cylinder heads other than Brodix.
The studs are not always drilled and tapped inline right angle square.

If you have lots of $$$$ shaft rockers & Rolker cam it.

Thanks for the input Brian. Concerning to hear that the studs may not be square in the first place... I guess you get what you pay for in some cases... and/or some companies just do things better..

I have very few $$$$.... I'm going to likely go with a flat tappet... just need to gather info on whether solid or hydraulic...

Hey Brian, just out of interest, what do you reckon a diff made by your hands, to handle a 400-450hp 383 in a Impala cost, shipped to Oz...?

 

[87vette81big]

A Roller Camshaft will not Give You A Magic 707- 780 HP Hellcat Power Alone.

A Street Friendly Hydraulic Flat Tapet Vs Roller Stree Cam will deliver similar results.
GO ISKENDERIAN FLAT TAPPET HYDRAULIC CAMSHAFT.
BEST THERE IS.

I am not sure what a Fank The Tank Rear Diff would cost to ship to Oz this morning .
Pretty sure $400-450 bucks.
I have sold items and shipped to Germany.
NOS GM 1969-70 RAIV LIFTERS & VALVESPRINGS.
IT WAS A $1,000.00 PAY DAY FOR ME.

 

[busterrm]

Hey Jimmy, try to find a set of 1 3/4 tube headers, you'll get some more hp/tq with that crane solid flat tappet cam. Retard it 4 degrees and you'll get about 418hp @ 6000 and about 414tq at 4500, that's estimate via DD2000.

 

[JimmyDuncan]

Hey Jimmy, try to find a set of 1 3/4 tube headers, you'll get some more hp/tq with that crane solid flat tappet cam. Retard it 4 degrees and you'll get about 418hp @ 6000 and about 414tq at 4500, that's estimate via DD2000.

A scan of Summit and a few other sites makes me think 1 3/4 full length headers for a SBC Impala are going to be hard to find..... lots of 1 5/8 about at good prices..... A few 1 3/4 "mid length" pipes for 4 x the price... I wonder if there are setups that are sold for other vehicles that will fit... ?

Using David Vizard's graph below, and the flow data you found for the Promaxx heads, I get a exhaust flow at max lift (.500?) of 170cfm. I'd be the green line, maybe purple, which are for best street use/street strip.. I get somewhere between 1.5" and 1.625" diameter exhaust pipe..? Does that mean that I could use 1 5/8" pipes? In saying that though, he mentions in the text that 1 5/8 is good for 200-375hp... So 400hp likely needs more huh?

I found some flow data on those heads:
Intake = .100 - 65, .200 - 137, .300 - 189, .400 - 224, .500 - 235, .600 - 234.
Exhaust = .100 - 62, .200 - 104, .300 - 140, .400 -160, .500 - 170, .600 - 174.

 

[87vette81big]

Small Block Chevies Prefer Full Length Long Tube Headers.

 

[JimmyDuncan]

Small Block Chevies Prefer Full Length Long Tube Headers.

Yep, that's why I didn't think the $650 mid length 1 3/4 pipes would be a good idea...