Summit 408 Short Block??

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Hmmm... I am not following the argument for flat top pistons here for the Edelbrock Performer heads. The 60179 head is not that far from the X/J head; the 'open' raised area is .060" deep on the 60179 as opposed to the .090" depth typical in the X/J heads. With a standard Felpro head gaskets, the total depth is almost identical. So I am not quite seeing that you can't use the 60179's....What am I missing ???

BTW if the 'domed' piston in a BPC4080 short block assy is a KB356, then the raised dome sticks about .075" out of an undecked LA block. With a 60179 and a standard Felpro head gasket, then you end up with around .045" clearance, and you'll have quench. But if the decks are cleaned up, it will be less. Perhaps the open chamber warning is to allow for some serious decking in the machining? (But heck, even X/J heads can have problems with too much decking.)

And the KB416's have no dome on the pistons. TNT, what heads are you looking at using? Just curious...
 
I worked with Mike at MRL Performance remotely (email and phone). Mike asked what I wanted out of the 408 and supervised the purchasing of all the components which I bought from MRL. I took my block to the local machine shop and had it all done up new to .030 and ready for the new Forged internal balanced Scat kit, Solid Roller VooDoo cam and Mikes Solid roller lifters. My heads will be here soon which were also purchased from MRL Performance.

IMG_3522 by Alexl5280, on Flickr

IMG_3521 by Alexl5280, on Flickr
 
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T-N-T said:
Ported RHS LA heads.
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Gotcha.... a true closed chamber head. And a popular one I would imagine. I can see where the 416 and that head and a thin head gasket would make a nice street combination. I think it would still have quench with a closed head and a 1121G head gasket with that small raised pad on top..... is this right?
 
nm9stheham said:
Gotcha.... a true closed chamber head. And a popular one I would imagine. I can see where the 416 and that head and a thin head gasket would make a nice street combination. I think it would still have quench with a closed head and a 1121G head gasket with that small raised pad on top..... is this right?
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Exactly.
It would have a good amount of quench, the dish portion matches the chamber shape nicely. It's either those pistons or forged Icon 745's. I'm just going for a healthy torque motor that will run on pump gas. I'll probably use Cometic head gaskets though.

If I build it myself odds are it will wind up with a forged crank & pistons along with some h-rods. I actually have a stock bore '72 360 sitting out in the garage. I should just have it machined and build it. My back wouldn't be too happy if I do though.
 
Nm9stheman

While the 1 Edelbrock head has a .060 relief in it, I would not call that an open chambered head, though it was designed for clearance with the domed stock positive deck height piston of the 340, what would make you think that the next dome would clear?

Different manufacturer(s) with different dome designs at different heights with different ..... The list goes on.

The way I normally build my engines is with a zero deck piston. Quench and to a small degree, compression ratio can be adjusted with the head gasket.

IF the build requires a low compression then a zero deck height may not be employed.
IF the build requires a better than 11-1 compression ratio & head milling for a smaller chamber doesn't cut it, then a domed slug is looked at. Not to start with. Or be hindered by.

I do realize that a MLS gasket can be order to suite.... Most cases, but not all cases. And that would depend on the flexabilty of the build, owner, targeted performance, etc....

Sometimes a domed slug is fine. High compression and a W2 headed race type engine come to mind. High octane or E-85 or alcohol.

I do not see A bennifit to this route on a street engine using pump swill.

I just want to know where the slug sits in the hole (and hope it is a zero deck for my taste or dished for a lower more pump gas friendly ratio.)& how many CC's the Pistons valve reliefs are. This way I know what I'm getting into. And where I might end up with as far as a compression ratio goes.

Just need to know. I'd flip out if I purchased such a part and assumed something that doesn't pan out. Then where do I stand? A piston way positive and it renders my closed chambered heads useless?!?!
 
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340sFastback said:
The 408 short block with the dished 20.5 cc pistons will work with closed chamber heads. Does not say if the pistons are zero decked or not:

HPE-SP57 - ATK 408 Chrysler Stroker Shortblock Engine FORGED Internals
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Not a LA block, can't use LA heads.
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T-N-T said:
Not a LA block, can't use LA heads.
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I agree. Even more so that I have a bunch of LA heads.

BUT

The remaining head selection is;
Any Magnum style head.
Stock heads - R/T - MP had a cross over head as well. Not sure if that would work.
EQ/RHS
Edelbrocks RPM
W2/TD machine rockers with oil through pushrods. I'm not sure if there is another manufacturer that has oil through pushrod to the rockers.

Not a bad selection of heads at all. Not one bit.
 
rumblefish360 said:
I agree. Even more so that I have a bunch of LA heads.

BUT

The remaining head selection is;
Any Magnum style head.
Stock heads - R/T - MP had a cross over head as well. Not sure if that would work.
EQ/RHS
Edelbrocks RPM
W2/TD machine rockers with oil through pushrods. I'm not sure if there is another manufacturer that has oil through pushrod to the rockers.

Not a bad selection of heads at all. Not one bit.
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Rumble, that was pretty much my thoughts as well. I'm still awaiting a piston PN, or further clarification on the note...but with the edelbrock RPM on the table..that suits 90% of the market needs in my opinion.

I'll be in touch when i know more. I have been slammed all day, but i do have a call in to BP.
 
rumblefish360 said:
I agree. Even more so that I have a bunch of LA heads.

BUT

The remaining head selection is;
Any Magnum style head.
Stock heads - R/T - MP had a cross over head as well. Not sure if that would work.
EQ/RHS
Edelbrocks RPM
W2/TD machine rockers with oil through pushrods. I'm not sure if there is another manufacturer that has oil through pushrod to the rockers.

Not a bad selection of heads at all. Not one bit.
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It still rules out LA replacement heads like RHS and Edelbrock RPM, their LA heads need the LA oil passage for rocker shaft. So I'm still SOL....


Johnny Pace said:
Rumble, that was pretty much my thoughts as well. I'm still awaiting a piston PN, or further clarification on the note...but with the edelbrock RPM on the table..that suits 90% of the market needs in my opinion.

I'll be in touch when i know more. I have been slammed all day, but i do have a call in to BP.
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Only if you buy the Eddy LA version without closed chambers for the BPC short block or use Eddy RPM Magnum or RHS mag head on the ATK short block.

The closed chamber non 340 clearanced LA heads like Rumblefish posted below are well over 10% of the market.

rumblefish360 said:
HOLD ON THERE JOHNNY!

Edelbrock heads are considered closed chambered heads. 65 & 63cc's. The 63cc head being the popular model. 65cc head for OE pistoned 340's with positive deck heights.

An example of an open chambered head is an X,O, etc letter heads, most every 360/340 head I ever crossed is an open chambered head. I'll re check my 308's, though I think there open.

W2's are a open chambered 70/72cc head chamber. Not all of them though. Some were as small as 65cc, 55cc & 47cc. I do not know of another aftermarket head that is considered an open chamber. Except the W2 70/72cc models. (Most popular by the way.)

The W5, 7, 8, 9 all had chambers ranging from 63 down to 51.

Since it is stated via the manufacture company of the create short block that it must use an open chambered head, this leaves any decent performance head OUT in the cold.

While we do have a few here that use a OE head on top of a 400+ cube engine, IMO, I can't see why and think no one in there right mind would use one. Except for towing? In all fairness to the OE head, it will port out right fine, just sadly short to allow the 408 to shine.

As I mentioned earlier, knowing what slug is used, where it sits in the cylinder (how far down in the hole or not) and the dome amount and height is a need to know issue.
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It all boils down to the pistons the BPC LA block uses. If they won't work with aftermarket LA closed chamber heads that will rule out 75% or more of the aftermarket LA heads that are available.
 
I love how every link connects me to a different female name to chat with, then suggests I buy a Chevy engine.
 
KnuckleDuster said:
I love how every link connects me to a different female name to chat with, then suggests I buy a Chevy engine.
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Yes, ignore the chat service. If you exit it once it should stop coming up for that session. Sorry, it annoys me also. Im doing what I can to support the mopar hobby. Wouldn't be here if I wasn't....working with vendors to come up with custom short block offerings hopefully shows my dedication. :)
 
Wasn't meant to be a jab, I thought I was being funny.
I actually have been investigating BP engines for a while for a friend, and if the customer service supports any mishaps, they look like a screaming deal!
 
KnuckleDuster said:
Wasn't meant to be a jab, I thought I was being funny.
I actually have been investigating BP engines for a while for a friend, and if the customer service supports any mishaps, they look like a screaming deal!
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Haha no you're good. I was jabbing myself also! The chat relay is pretty laughable. Agreed.

Id love to tell you about my experiences with blueprints warranty, but the fact of the matter is I haven't had to warranty one in probably 5 years. I do speak to their manager regularly though, and they are great and stand behind their products. Good people. I wouldn't hesitate to run one any day.
 
So are the following statements true?
A) The "open chamber" Eddy LA heads are #60175 & #60179.
B) The "closed chamber" Eddy LA heads are #60775 & #60779.
C) A Blueprint short block with forged crank & forged pistons, with internal balance, could also be supplied for use with either of the above heads.
 
69_340_GTS said:
So are the following statements true?
A) The "open chamber" Eddy LA heads are #60175 & #60179.
B) The "closed chamber" Eddy LA heads are #60775 & #60779.
C) A Blueprint short block with forged crank & forged pistons, with internal balance, could also be supplied for use with either of the above heads.
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C is incorrect. The blueprint short block is not forged and is external balance. Although I can match either head to it.

The ATK I offer is forged and internal...but...its a magnum. So you are buying magnum heads at that point.

I suppose if you are set on forged, internal bal, and LA...im out of options.
 
Johnny Pace said:
C is incorrect. The blueprint short block is not forged and is external balance. Although I can match either head to it.

The ATK I offer is forged and internal...but...its a magnum. So you are buying magnum heads at that point.

I suppose if you are set on forged, internal bal, and LA...im out of options.
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Thanks Johnny. ATK shows a "ATK SP64 Chrysler 408CI Stroker Short Block -20.5cc Dish Pistons A Block Forged Crank Kit" on their web site. You don't sell that one?
 
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