Are there off-the-shelf heads that do not require additional work?

[lefty o]

afr195 or something else of similar quality/size will easily do 450hp.

[77cruiser]

I'd be tempted to use these.

http://www.high-performance-engines.com ... c70185.htm

[af2]

RHS 235 have been good!
Ferrea valves and nextec springs with Yella terra rockers.

[lefty o]

RHS 235 have been good!
Ferrea valves and nextec springs with Yella terra rockers.

you dont think a 235 might be just a tad big for a 450ish hp 350?

[Newold1]

For that power level of 450HP out of a nice 355 with the correct cam, intake manifold, 750cfm carb and headers on pump gas my call is the ProMaxx Maxx series 225cc head with 2.08 intake complete ready to run out of the box for $950 a pair is the set to buy. Correct cam , intake and carb are critical to make this right but that is necessary which ever heads are used regardless of brand. JMHO

[V Remian]

Edelbrock Performer would be my choice.

[rfoll]

GMPP Fast burn heads would work well, but I can't speak to the condition as delivered.

[randy331]

For that power level of 450HP out of a nice 355 with the correct cam, intake manifold, 750cfm carb and headers on pump gas my call is the ProMaxx Maxx series 225cc head with 2.08 intake complete ready to run out of the box for $950 a pair is the set to buy. Correct cam , intake and carb are critical to make this right but that is necessary which ever heads are used regardless of brand. JMHO

RHS 235 have been good!
Ferrea valves and nextec springs with Yella terra rockers.

Too big x 2.

Randy

[Newold1]

Yah Randy I think you might be right really don't need those big cc's to get to 450Hp at that build. I resubmit the ProMaxx Maxx 200cc 64 cc head with a 2.02 intake with 270 cfm @.550 lift and $970 a pair out of the box will get him there. Great price for a nice quality and performing cylinder head.

[randy331]

Yah Randy I think you might be right really don't need those big cc's to get to 450Hp at that build.

It's not just you don't need it, but you'll most likely be worse off with that size (225cc).

He has 355 cubes and stated low 6000s rpm limit.

How big of CSA works at that rpm ?

Randy

[steve cowan]

I calculate
355 ci @ 6000rpm needs a MCSA 1.95"
Intake runner size 175-180 cc approx
240 cfm
250 fps average if you can get it
What do you think randy

Steve C

[randy331]

I calculate
355 ci @ 6000rpm needs a MCSA 1.95"
Intake runner size 175-180 cc approx
240 cfm
250 fps average if you can get it
What do you think randy

Steve C

What are using to figure that ?

Randy

[Old as Dirt]

Profiler 210cc around 550.00 ea. bare, 2.08 valve job.. would be my choice.. Valves, springs, retainers and locks to suit your combo..

[Mark O'Neal]

The definition of "bolt-on" is "you don't have to weld it"

[steve cowan]

I calculate
355 ci @ 6000rpm needs a MCSA 1.95"
Intake runner size 175-180 cc approx
240 cfm
250 fps average if you can get it
What do you think randy

Steve C

What are using to figure that ?

Randy

hi randy,
for a approx starting point i use
MIN CSA - bore x bore x stroke x rpm x 0.00353 (math constant) / 613.8 fps ( 0.55 mach x 1116fps)
eg - 355 ci @ 6000 rpm
4.030 x 4.030 x 3.48 x 6000 x 0.00353 = 1197 / 613.8 = 1.95'' csa
port volume cc
min csa x 5.45'' (average intake manifold runner length approx) x 16.387 (math constant)
1.95 x 5.45 x 16.387 = 174 cc approx
then i put the parameters into engine pro software
355ci
4.030 bore
3.48'' stroke
5.7'' rod
10.5:1 comp
cylinder head 240 cfm @ 600 approx
2.02 int
1.54 -1.6 '' exh
150 cfm exh 63% of intake
242 roller cam 600 lift
449 hp @ 6200 rpm
419 lb/ft @ 5000RPM
205 psi cranking pressure
cam LSA and ICL as we know is a debatable subject and i dont have the knowledge to have an informed opinion
so i will leave it alone
i dont take engine pro as gospal but i think it is a starting point for people as myself with limited skill set.
randy,
if i am out in left field please feel free for constructive feedback as i would like to know all your speed secrets

steve c