need some help with selecting cylinder head Mopar 408

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mopar_persson

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hey i need some help choosing heads for my (360) 408 stroker.

This is in the engine

probe 408 Flat Top -5.5cc - SRS Piston
scat 4" cast, crankshaft
scat I connecting rods
mopar purple cam P4120230
COMP Cams Pro Magnum rockers
edelbrock rpm airgap intake
holley 750 db

and the heads i am using now is, 360 G "4027596" with 1.88-inch intake valves, 1.600-inch valves at the exhaust, the heads is not ported.

I want to get so much hp as possible on this engine,
but I do not want to fuss with W-2 / W-5, heads.
What should I use for heads?? Edelbrock 340 rpm any good?

I am also considering changing camshaft if needed

excuse my english I'm from Sweden.
 
I've seen others on here recommend Edlebrocks and Indy/RHS X-heads for similar builds.
I bought a pair of Indy/RHS X-heads prepped by IMM engines, for a 340 build i am doing.
Hopefully others will chime in with more info for you.
Steve~
 
my 410 runs the RHS heads from Brian at IMM give him a call he also can put you on the right path with your cam , he built my LA with a roller cam and saved me all the hassles of break in and zinc , best phone call you can make in my opinion even if you buy something else in the end he will teach you a lot in very few words .
 
Not sure the pin height on that piston, but if it's close to zero deck, you're gonna have to watch where your compression ends up with aftermarket heads. What type of fuel do you use? I'm not familiar with the quality of pump gas in your area. The cam selection can bleed of some compression if need be.
 
What camshaft is that? I can't find the number.
The pistons - SRP is the manufacturer? You will find it easier to get a reasonable compression ratio with good quench if you use the 16.5cc dished piston.
 
moper said:
What camshaft is that? I can't find the number.
The pistons - SRP is the manufacturer? You will find it easier to get a reasonable compression ratio with good quench if you use the 16.5cc dished piston.
Click to expand...

Moper, i agree. I think this is what he has and they look like they would zero deck. I can see a pretty big number with a 62/65cc head.

http://www.campbellenterprises.com/parts.php?type=search&query=pro13746030

http://www.campbellenterprises.com/pistons/probe-pistons/probe-mopar-360-forged-stroker-pistons.htm

1.476
2.00
6.123
=9.599
 
OldmanRick said:
Not sure the pin height on that piston, but if it's close to zero deck, you're gonna have to watch where your compression ends up with aftermarket heads. What type of fuel do you use? I'm not familiar with the quality of pump gas in your area. The cam selection can bleed of some compression if need be.
Click to expand...

the pump gas i use is 98 octane
the cam is a P4120230 but when you order it the number is P4120231
http://www.summitracing.com/parts/dcc-4120231ac/overview/make/plymouth

(moper)
so i maybe need to change the pistons? :(
I have a pretty tight budget for the heads 2325 $ is the max i can afford right now.
 
I just recently bought some Edelbrock heads for my 318 that are on their way to Australia!

Forget the "Edelbrock vs RHS" pissing contest you read everywhere on this site. it doesn't apply to us.
Sending cast iron heads internationally isn't a very good idea coz of the weight. ($$$)

The bare version of the Edelbrock head is 60769 and can be bought from amazon for $573.89

[ame="http://www.amazon.com/gp/product/B0006300VU/ref=ox_sc_act_title_3?ie=UTF8&smid=ATVPDKIKX0DER"]Amazon.com: Edelbrock 60769 SBM Performer RPM Cylinder Head - Bare: Automotive[/ame]


It seems like there's a large import tax for importing into sweden.
You should be able to get these for about $1600-$1700 USD including all taxes and shipping cost.

Keep in mind these are for BARE heads, you will still need to buy valves, springs, retainers and collets and then there's machining etc.

Phone summit racing and get them to do a price match. don't buy from Amazon, they don't have any customer service and WON'T help you if your heads go missing/damaged.

I've had lots of good experiences with summit and their international shipping to Australia.

PS. that's cam's a bit tame for a 408. is it going to be for a daily driver?
 
I´ve bought a set of IMM Engines RHS X-Heads. Shipping was not too much to Europe since i used a container Import service. Brian shipped these heads to Florida. I think these are the best bang for the buck at the moment.

The Heads are ok, good quality, good work. But don´t expect "the most HP possible out of this engine" with these. Typically the Engines using these Heads are in the 450-490 HP Area, same about torque numbers (IMM has got some links on the Homepage to magazine articles, very informative).

If you want to go beyond, then the best bet would be a fully ported EDE Head if W-Series Heads are not an option.

Michael
 
True, sea freight is a cheaper option, but expect your heads to be available for pickup around easter by the time customs checks it out and all duties, taxes and fees are paid:tonqe:

The reason i mentioned the tax is because usually this is charged as a percentage of the item value + freight value combined.

Shipping to sweden should only be about $70 each, but the TAX is hundreds. this will almost definitely be the same whether you go air freight or sea freight.

In my case the Edelbrock heads cost around $80 each to ship via air freight.

Australia has no tax for items valued under $1000USD but we also have a pathetic postal service.

I'm in a rural area and my imported parts usually get to Australian shores in 3 business days then another 10-13 to get to my local post office which is a 50minute drive from the state's head post office in Melbourne..

This is the case regardless of whether I use USPS, or a courier company like UPS, FEDEX, DHL etc

(They just cost more and aren't any quicker)

We have arguably the most thorough and stringent customs in the world, and as a result extremely slow international mail on our end.

I'll stop ranting now, I promise
 
Also if you choose to go for RHS cylinder heads, make sure your comp rockers will work with them.

there have been cases of some heads that have an issue with some brands aftermarket roller rockers. (not all heads and not all brands)

http://www.forabodiesonly.com/mopar/showthread.php?t=174593&highlight=RHS+rocker+geometry

These forums have plenty of highly reputable engine builders/machinists who can point you in the right direction in determining this

I personally could only recommend machinists/engine builders I've had work done with inside Australia.
 
mopar_persson said:
the pump gas i use is 98 octane
the cam is a P4120230 but when you order it the number is P4120231
http://www.summitracing.com/parts/dcc-4120231ac/overview/make/plymouth

(moper)
so i maybe need to change the pistons? :(
I have a pretty tight budget for the heads 2325 $ is the max i can afford right now.
Click to expand...


$2325US? That's not bad.
Your 98 octane is the equilvilent of our 93. It's not that good...lol. The flat top pistons will make the static ratio too high, and honestly - that cam is too small to work with any pump fuel 4" stroker. What I would suggest is to modify your plans like this:
Replace the pistons with SRP dished - 16.5cc, D shape, set to be proud (above the deck) .005".
Run Out-of-the-box RPMs with the 63cc advertised chambers. They ar $1500 plus frieght, and all you'll need is to have the valve job checked and the springs replaced to match your camshaft. You will also need the ARP bolt package for them. I would think that will be close to $2300US in total.
Run the Fel Pro Performance .039 compressed head gaskets (recommended by Edelbrock).
Run a camshaft of at least 240° @ .050, preferrably something around 245° and lift around .530. Something like the XE284H or my perenial favorite the Crane H302-2 would do it for a hydraulic - or the solid MP P4120655 (although I'd consider any MP design to be the last possible choice... there's so much better out there.)

That's what I'd do.
 
Respectfully, I would recommend against buying assembled Edelbrock heads if you're going to throw the valve springs away and get a reputable local machine shop to check/re-grind the seats.

Especially when you're paying heavy import tax on parts and labor you're not even going to make use of.
 
The rating system of the U.S.A. vs the European methods vs. .......
 
I think what we're getting at is with his current piston, aftermarket chambers will put him well over 11 to 1, and that may be a stretch with pump fuel. Even with alum. heads, depending on cam timing.
 
wouldn't it be a lot cheaper to masssage the chambers to 70cc and use a .060" head gasket?

With a zero deck that would make about 10.5:1
 
frosty_the_punk said:
wouldn't it be a lot cheaper to masssage the chambers to 70cc and use a .060" head gasket?

With a zero deck that would make about 10.5:1
Click to expand...

Yes......not quite as efficient as a small chamber & dish in my opinion, but yes.

I just wanted to bring attention to compression in this thread so he didn't end up having to cam the bottom end out of it to get the dynamic comp. in line. The beauty of the 408 is the torque it makes between 2500 and 5000 rpms. Even with better heads, if you have to pull lower end torque out by camming up for pump fuel, you'd end up compromising the overall average power output by just moving it upstairs making the mod less cost effective in my opinion. Hope that makes sense.....:D.
 
98 octane is pretty good compared to what we have here. You should be able to run more than the 10-1 limit we use with alum heads and 91 octane gas. I am guessing that you could run 11-1 with alum heads.

I would suggest contacting some of the engine builders here and discussing a set of Eddys that they buy bare and then set up for your cam and compression. They should be able to make the paperwork seem like the heads were cheaper than the actual cost to help with the VAT, and you will get the springs / valve travel you need for your combo.
 
the problem with fudging item values for tax purposes is that insurance is based on the same evaluation.

Risky!
 
frosty_the_punk said:
Also if you choose to go for RHS cylinder heads, make sure your comp rockers will work with them.
Click to expand...

Rocker and retainer/spring interference is an issue with ede heads too. Happens on stock x/j heads as well.
 
mopar_persson said:
hey i need some help choosing heads for my (360) 408 stroker.

This is in the engine

probe 408 Flat Top -5.5cc - SRS Piston
scat 4" cast, crankshaft
scat I connecting rods
mopar purple cam P4120230
COMP Cams Pro Magnum rockers
edelbrock rpm airgap intake
holley 750 db

and the heads i am using now is, 360 G "4027596" with 1.88-inch intake valves, 1.600-inch valves at the exhaust, the heads is not ported.

I want to get so much hp as possible on this engine,
but I do not want to fuss with W-2 / W-5, heads.
What should I use for heads?? Edelbrock 340 rpm any good?

I am also considering changing camshaft if needed

excuse my english I'm from Sweden.
Click to expand...

Surprised nobody else caught this, but if you do go Eddy, then don't get the 340 version.
And Moper is spot on about the octane ratings over here, our premium 98 octane is about the same as your 93.
 
Do t guess or assume, YES!!! 11-1 is totallllly doable with aluminum heads!
BEEN THERE DONE THAT AND STILL DOING IT NOW!!!!
With a very very similar cam!

The air wolf heads are promising but you will have to look carefully at there specs before you purchase them. Look at more than just the flow ratings. Port window size and valve size.
 
i would stay away from the 340rpm heads,why you might ask? i have a set and it was a stupid buy,should have gone for closed chambers and payed alitle more to get pistons that where at zero deck instead. regular rpmheads works good.just calculate your true compressionratio and you will figure it out if it works or not:)

have a look in the ads on http://www.nitroz.se/ i bet i have seen some RPM heads and also Indy X heads not that long ago over there and sometimes you are lucky with moparstuff that is put up there since it may not sell for a fairly long time:) i would look for you but right now my blonde thingy i live with needs a hand with something..
 
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