390 w/open chamber heads

[Treblig]

Txstang84,

You make a lot of sense. I'll look around for an RPM, if I could just trade one of my bead blasted, clear coated Performers for an RPM it would be great!! Lucky for me I have lots of time. I still need to order the adapter plate and cut it down like "Mopartoya" did. I was hoping there would be a Christmas sale at one of the places that sells the TCI adapter.
If anyone wants to know why I settled on the TCI (yes, it is cheaper) but more importantly it's only 1/4" thick (at least that's what they told me when I called). The people that sell the Wilcap said that their adapter is 3/4". the thicker the adapter the more you move the trans back and the more you have to cut out of the upper trans brace/support.
If anyone reads this thread and has used either one of these adapters please verify the thickness (and let me know for sure) as it is very important when it comes to hacking up your MOPAR!!

Treblig

 

[340sFastback]

You don't need to mill the heads for what you are trying to do you will have to settle for 9.0 - 9.5 compression but that should be fine given your goals. But like Moper and others have said run a performer RPM intake manifold. The ports are better suited for what you are trying to do. Pay attention to what Moper said in his post, he has built a lot of 4" stroke engines and has tried a lot of different combos so he knows what works. I run the cast crank Scat stroker kit with dished Icon forged pistons and I am pushing well over 500 hp and its been together for quite a few years and it gets tested quite frequently....

 

[Treblig]

340sFastback...Nice Cuda Dude!!!

I'm leaning very heavy toward the RPM (now to find one for a good price). Then again, what's all this hullabaloo (sp) about A/C clearance using the RPM??? Great info on the Scat cast crank...makes me feel better about saving some money over the forged and still get good performance and reliability. Based on your testimony I'll probably go with the Cast Scat crank.

thanks,
Treblig

 

[Treblig]

After thinking about it for a while I came to the conclusion that I really have no reason to complain about the extra cost of the RPM. if I get a cast crank I'll save about $400.00 so even if I buy a good used RPM intake I'll still come out way ahead!!!
Nobody had any input about getting a custom cam from Hughes?? Is this also not necessary????
And nobody chimed in about getting the correct push rod length??

Treblig

 

[FrostyMopar]

Read this

http://www.moparmusclemagazine.com/techarticles/engine/mopp_0108_dyno_testing_small_block_intakes/

The RPM manifold is completely unnecessary to get 325 horsepower from a stroker.

You already have the performer and it's a good unit, capable of far exceeding your requirements.

It's really easy to get suckered in to spending a little more on performance parts you probably don't need.

Build a good short motor and everything else can be chopped and changed at a later stage.

Often times a 13 second engine can be turned into a 11 second engine with the same rotating assembly but new intake, cam and heads.

If and when you want more power later on, buy the RPM and put it on. (budget pending)

 

[Treblig]

Frosty_The _Punk,

Brilliant!! You're right, I can easily build it with the performer see how it runs then get a RPM , gasket match it and swap it out later. It will save me money now and give me time to save more for the RPM, If I even need it. Because if the engine has the omphhh I'm looking for using the Performer I'll leave it like that and have fun. Then later if I want more I can always switch.
340sFastback suggestion to use the cast crank has already saved me $400.00, that pays for a good portion of the pistons (it's almost like free pistons).
Now on a serious note...Will I rip the car apart with 4.10 gears and that low 200R4 1st gear????? I'm running a narrowed Chevy 10 bolt (new) posi with 30 spline 12 bolt axles so the rear should hold up. I would have used a Mopar rear but they are very rare around here (unless you're rich).

I wanted a good launch off the line, I can't imagine what 4.10s would do with the 200R4 first gear???


Treblig

 

[txstang84]

You can usually feel pretty secure purchasing stock length pushrods as long as nothing has drastically changed during your build like block and/or heads shaved more than about .040", longer valves, something like that...

That being said, IMO, pushrod length should be verified during engine mock up by checking the contact patch on the valve tip...

 

[txstang84]

If I were back in Abilene, I could sell you a B body 8 3/4 housing...but I'm not.

Regardless of what gears you put out back, you also need to think about chassis and suspension upgrades-the power you will have would be utterly useless (with exception to roasting the goodyears) without traction. Subframe ties are very nearly a requirement for an A body

 

[Treblig]

Yea, I could fabricate some subframe connectors pretty easy!! Piece of cake.

As for the push rods, I already have two pairs of stock rods. And even though I've read a lot about decking the block down to zero deck height I don't think I need the extra cost for my torque monster...???

'mI also very aware of checking the scrub on the valve tips using weak springs.

Treblig

 

[txstang84]

Zero decking isn't always a requirement, and it's really only important if you're building an engine to take full advantage of quench...which, from what I can tell, you're not. That being said, not squaring up the decks is just a little bit lazy. It's typical for these engines to not have square or flush decks, and that can lead to issues later.

 

[Abodybomber]

Now on a serious note...Will I rip the car apart with 4.10 gears and that low 200R4 1st gear????? I'm running a narrowed Chevy 10 bolt (new) posi with 30 spline 12 bolt axles so the rear should hold up. I would have used a Mopar rear but they are very rare around here (unless you're rich).
No ,usually gears relax the load on everything. Transmission brakes/drag slicks kill parts/transmissions. Trade off for quick dragstrip times. Pretty car,had a 67 notch,same color.

 

[Treblig]

thanks Abodybomber, I love my Barracuda!! Makes no sense...I'm a Chevy guy through and through but ever since I saw the "Hemi Under Glass" many, many years ago I fell in love.
That was one wild ride!!!

No trans brake or slicks for me but if a Mustang revs its' engine when I'm sitting at a light....WATCH OUT!!!

treblig

 

[Treblig]

Ok so the final (maybe semi-final) analysis is :

Cast scat 4" stroker crank
ferrea 2.02/1.6 SS valves
SIR6123 forged steel rods
mildly ported 2176 Performer ( to be replaced with RPM if necessary)
Ported heads and gasket match
92-02 Mag truck exhaust (340 on driver's side) already installed
2 1/2 twice pipes with cross over already installed
Edelbrock 1406 600CFM carb
4.10 gears (RRR)
200R4 (with shift kit and other mods)
sub-frame connectors
adjustable rockers
custom cam
stock push rods
Chevy 10 bolt posi (already installed)
stock converter
596 open chamber heads (ported) CC the heads
TCI adapter

I want to thank everyone who participated. I should be good for now until something else pops up!!


treblig

 

[dirty white boy]

pistons??

 

[70aarcuda]

change out the 5140 Eagle SIR rods for the 4340 Scat I beam rods... a lot better rod at about the same price..

 

[Treblig]

Dirty White Boy,

I can't order the pistons until I know my combustion chamber CCs. The compression height on the piston is determined by chamber volume (and deck height) for the compression ratio I'm aiming for 9.5 to 1 (I think??).

70aarcuda,
I owned a '70 Cuda (440 6 pack, silver glitter shaker hood) for about 1 week back in 1975. I bought from the original owner (25K miles, just like new) who didn't like the amount of power it had. Purchased it for 3K and (LIKE A BIG DUMMY) I sold it the next week for $3500.00. Somebody kill me!!!!! That car was PERFECT!!!!!

I already have the rods (SIR) but I appreciate the input. I got the rods basically brand new for $200.00 from someone who had given up on a project (Mopar). Remember, I'm building a torque monster so no high RPMs needed (5500 and below).

Treblig in Tex

 

[txstang84]

The compression height on the piston is determined by chamber volume (and deck height) for the compression ratio I'm aiming for 9.5 to 1 (I think??).

Unless I misunderstood you, I think you mean to say the amount of dish in the piston...the CH of any piston is the measurement from the pin bore center to the crown of the piston (dome/dish notwithstanding).

And if you're looking to make a specific compression ratio, yes, you would do well to figure out what your chambers measure out to, what kind of head gaskets you will use, and then you can take the actual block deck height measurement into consideration to figure out which over-the-shelf pistons you want to purchase...unless of course you're wanting to go custom.

 

[moper]

On the pushrods - do not assume the stock ones will work. Even if you're not square decking (which I totally disagree with) the differences in factory machining even side to side, plus the work on the heads, plus the necessity of setting the proper preload with the rockers - you will need to measure for the right length (or lengths depending on how messed up the deck is) and then order them. Pushrods are always the last parts I order.

 

[txstang84]

moper, you totally disagree with square decking-why? Would it not establish proper geometry in the block, and valvetrain? Perhaps I misunderstand the concept

 

[Treblig]

txstang84, you got it! and yes I'll try for off the shelf pistons...one can hope??

Moper, the push rods will be ordered after a mock-up build with (fake) adjustable push rods and light valve springs. I'm not assuming anything but I do have adjustable rockers which should make up for minor differences. If the valve stem scrub isn't correct then I'll have to get new push rods...correct????

txstang84, trying my best to build a 390 torque monster (strictly a street car with no drag racing). As such, do I really need to deck the block?? I can deck the block, I have the money but do I need to for my purposes (street sleeper), no high RPM & 200R4?

Treblig in Tex

 

[txstang84]

This is what I'm trying to figure out with moper.

it's been my understanding and experience that decking a block prior to boring is a good idea--even if it's not zero decked to blueprint spec, just evening out the deck measurement side to side is a good idea since factory tolerances were often...lackluster...0.004" here or there could lead to warpage and ill sealing head gaskets.

Perhaps though, that's why he disagrees with square decking a block; possibly he's seen it in the past where square decking actually caused ill sealing gaskets...or possibly it's because using a boring bar that doesn't index off the pan rail can actually cause cylinders not properly machined after decking...that's what I'm tryin to figure out.

 

[Treblig]

Yes Txstang84, It is a good practice to deck a block when building a HP engine. Buy I'm not shooting for a HP engine, just a simple torque monster with no high RPM capability (6000 and below).
I can't see a big benefit to spending money on decking the block, it's not a bad idea but it may not be what I need for what I am building.
I'm going to use this car to take my little girl to school each morning then blow somebody away on the trip home!!!

Treblig

 

[RustyRatRod]

Everything is related off the crank center line in an engine. Square decking = good.

 

[64 SRT8 Dart]

Just a little note about the Performer 318/360 intake....the ports match up perfectly with 318 2bbl intake gaskets. Felpro # 1243 2.08 x 1.05 ports.

You may want to get a F/p# 1213 w/ 2.27 x 1.16 port and see how it matches to the intake and your heads, possibly matching both intake and head ports close to eachother with it if you do any gasket matching.

I'm running the Performer on my 318 and matched my 318 2bbl heads to the 1243 gasket, there was a HUGE difference between the 2bbl gaskets and my 2bbl heads. See pics.

P.S. I didn't do anything to the intake, again, as now it all matches up perfect, nice smooth transitions and everything!!....already test fitted everything to the block.

 

[txstang84]

Yes Txstang84, It is a good practice to deck a block when building a HP engine. Buy I'm not shooting for a HP engine, just a simple torque monster with no high RPM capability (6000 and below).
I can't see a big benefit to spending money on decking the block, it's not a bad idea but it may not be what I need for what I am building.
I'm going to use this car to take my little girl to school each morning then blow somebody away on the trip home!!!

Treblig

Have you ever heard, or used the saying "consistency is key"? I'm not telling you it's a necessity, specifically, I said--and this is only MY opinion, so it and $1.50 might buy you a cup of coffee at a 7-Eleven...

Zero decking isn't always a requirement, and it's really only important if you're building an engine to take full advantage of quench...which, from what I can tell, you're not. That being said, not squaring up the decks is just a little bit lazy. It's typical for these engines to not have square or flush decks, and that can lead to issues later.

I'm not trying to build your engine or machine it for you-you asked for general opinions, and I submitted mine. You can obviously feel free to disregard it as just another guy using buzz terms or talkin' out his *** because he's read too many issues of "Hot Rod" or "Popular Hot Rodding" or whatever publication floats your proverbial boat, all I am saying is that making consistent measurements--even if they're not blueprint specs--creates consistent measurement inside the engine...consistency is directly related to longevity, reliability, and efficiency.

Even if you don't zero deck the engine, at least get a clean up cut so the gasket has a good surface to mate to and things like pushrod preload and compression ratio are consistent from one bank of cylinders to the other.

I understand you're not shooting for an "HP" engine, but I doubt severely you're looking to pour money into a fun investment that may have more compression on one side (however minute it may be) or more valve lift on the other. Opinion typically insinuates you're asking someone what they'd do if it were theirs. If I were building a 390 with my own parts, I'd lay down the extra $125 it costs to deck the block-if not zero, certainly equalized, but that's just my .02...and I'm still curious of the rationale behind not square decking a block for the same reasons I mentioned above...