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Dressing out a New Engine

Windy Bay

Contributing Member
I just had a new engine built, a 383 stroker (yes Rick I used D dish pistons) and I am looking at things like intake manifold, valve covers, Oil pan, and timing chain cover. Does the pan need to be anything special for marine. If I use aluminum is there a better way to protect it, so it doesn't look like crap in 2 years? same with the rest of the coverings ie valve covers and timing chain cover. I am considering aluminum and powder coating? If someone made stainless steel I would go that way, but I can't find SS. Input would be appreciated.
 
I just had a new engine built, a 383 stroker (yes Rick I used D dish pistons) and I am looking at things like intake manifold, valve covers, Oil pan, and timing chain cover. Does the pan need to be anything special for marine. If I use aluminum is there a better way to protect it, so it doesn't look like crap in 2 years? same with the rest of the coverings ie valve covers and timing chain cover. I am considering aluminum and powder coating? If someone made stainless steel I would go that way, but I can't find SS. Input would be appreciated.

The intake manifold will be specific to the cylinder head bolt angle. There was a change to the cylinder head/intake manifold bolt angle on the pre-Vortec engines.

The Vortec intake manifold will not fit onto the earlier cylinder heads.
Since you went with the D-dished pistons, I assume that you did NOT use the Vortec cylinder heads.

The timing chain cover will be determined by the type of camshaft.
Early flat tappet cam engine does not require any thrust button, whereas the roller cam set up does.


As for an oil pan, I'd go with one with a larger sump volume.

I just recently visited a company who does powder coating. It's quite an interesting process!
If you have anything powder coated, make dang sure that it is aggressively sandblasted prior.



.
 
I should have given all the details. I am replacing an aq271.
the new engine:
1990 gm Block 1 piece rear main
Scat steel 383 crankshaft
Gm 350/5.7 connecting rods W/HD 150,000 bolts
Keith Black KB 135 pistons
Marine Camshaft .480/.489 - 226/236 - 112 specs
Lifters Flat tappet hydralic
High Volume oil pump
HD double row timing set
brass freeze plugs
GM 76cc 1.60/2.02 cylinder heads w/hardened valve guides, seats
stainless steel swirl polished 1.60/2.02 valves
comp series valve springs .530 max lift
elgin hardened push rods
gm 1.5 ratio rocker arms, ball & nuts

So no on the vortec heads.

I would like to keep the intake manifold I have. BUT this engine that I am replacing is a salt water boat, and is not fresh water cooled. the manifold is GM part 14096242. When I googled this manifold it gets rave reviews. I am worried that any salt and other contaminants could cause me problems, as I am putting on fresh water cooling on the new engine. I am researching how I might clean the intake. I have had aluminum parts on a marine engine and after a couple of years they look like crap, and as anyone who uses a boat in salt water knows the steel, will rust fairly quickly. So I am researching alternatives to the dressing parts, ie valve covers and the other parts I mentioned. I am thinking about this oil pan, and maybe powder coating

https://www.summitracing.com/parts/mil-30907/overview/make/chevrolet.
I was thinking about these valve covers, but I need them in center bolt configuration. Haven't found anything in the way of timing gear cover, and still debating between aluminum and steel

https://www.amazon.com/Small-Raised...t=&hvlocphy=9033085&hvtargid=pla-803797542866
 
The KB 135 piston shows up as this:

Keith-Black-KB135-030-Dished-57-Rod-Chevy.jpg



Summit, Jegs and CNC MotorSports call out a dish volume of 18cc!

Your cylinder head chamber volume is 76cc.

[FONT=&quot]Throwing some realistic numbers into an on-line calculator (with a .043" quench dimension), this puts you in the neighborhood of 8.6:1 static compression ratio.


[/FONT]
I see no issues in using the
[FONT=Helvetica Neue, Helvetica, sans-serif] [/FONT]GM 14096242 cast iron intake with a Closed Cooling System. You can also use a Dual Plane Aluminum intake with the Closed Cooling System.

Haven't found anything in the way of timing gear cover, and still debating between aluminum and steel


Above you mention "HD double row timing set", as in chain/sprocket driven.
Are you now going with a gear driven cam?
[FONT=&quot]


.
[/FONT]
 
Dang it! I had a shop in portland do the work, and I am going to call them in the morning. I had to go out of town on Monday morning and I just got back. I was aiming more for 9.5 to 1 on the static C/R. I re read some of the threads here, and the place I think I messed up was with the cylinder head chamber volume. Before I started this endeavor I did a lot of reading here. I tried to find Dennis Moore's book, but unless you want to pay $800 dollars, that is a no go. I am working with this shop because I saw an ad for them advertising stroker motors. But they were using a dome piston. they advertised a 9.4:1 compression ratio, but that was with the domed pistons. they were advertising 420HP and 430ft lbs torque. It will be interesting to see if they will assist. Thanks again Rick. Seems I learn best when it cost me more!
 
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Dang it! I had a shop in portland do the work, and I am going to call them in the morning. I had to go out of town on Monday morning and I just got back. I was aiming more for 9.5 to 1 on the static C/R. I re read some of the threads here, and the place I think I messed up was with the cylinder head chamber volume. Before I started this endeavor I did a lot of reading here. I tried to find Dennis Moore's book, but unless you want to pay $800 dollars, that is a no go. I am working with this shop because I saw an ad for them advertising stroker motors. But they were using a dome piston. they advertised a 9.4:1 compression ratio,
Bear in mind, that most of these shops are building Auto engines, not marine cruiser engines. They often lack complete information in their ads, such as the piston profile and cylinder head chamber volume.


but that was with the domed pistons. they were advertising 420HP and 430ft lbs torque. It will be interesting to see if they will assist. Thanks again Rick.
Seems I learn best when it cost me more!
I agree....... that appears to be the case with many things.


Rick, More of a direct question would be is the 8.6 to 1 compression ratio too low?

I'm reluctant to make suggestions like that.
For me, yes..... that would be on the low side.
The static compression ratio refers to the sweep volume. The actual dynamic C/R will be lower, and is determined by the camshaft profile and how well the cylinder heads flow, etc.
(see hyperlink below)
By the way, this info is not necessarily for high performance only. You won't be building a Hot Rod engine!

https://www.enginebasics.com/Advanced%20Engine%20Tuning/Static%20vs%20Dynamic.html

As a general rule, when the quench dimension is kept tight, we can go a few points higher on the S C/R without any issues.
You want to take advantage of the additional .270" stroke in order to produce torque.
A tight quench allows for a greater ignition TA, causing the LPCP to occur closer to where it should be.




,
 
Rick, Thank you for the reply! The learning curve on building a VERY GOOD marine build is significant. I need to get this shop set straight, because of 2 things. This was advertised as a marine build, and when I picked up the engine they indicated that they were going to start using this piston as a more standard piston for their marine build. I shared quite a bit of information with them during the build process. I requested the D dish piston, not actually selecting the piston. And to be honest I don't know which piston I might of suggested. My passion is in the use of the boat for fishing, and boating. I am by no means the expert that some on here are. It takes time to learn, and for me part of learning is seeing where I went wrong and why. I have to rely on the shop and others for information. With most shops you get a deer in the headlights look when I start talking a good marine build. These guys want to get an engine built and out the door, so they can get paid. Even places like major companies, who I won't name supply hundreds of engines are using full dish pistons, and in the case of the shop I am using dome pistons for a marine build. It gets very frustrating.
 
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Rick, I have done some more research this am and have found some new info. First I was going from the builders original ad. This is not what I got! The pistons are KB135.040. But the heads are NOT 76CC. I got the casting number from the head which is 14102193, which comes up as a 64 CC head. One of the things that i read is that these may measure out to 65.3. Don't really know, but the manufacturer says 64cc? 14102193...87-up...305/350......1.94"/1.5" valv. so when I look at the specs on united engine machine for the exact piston, they say 9.7:1 c/r https://www.jegs.com/i/United-Engine-Machine/648/KB135.040/10002/-1. Better than 8.6: These according to what I read were TBI heads, and are not racing heads (Which I am not looking for anyway) better?
 
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Rick, I have done some more research this am and have found some new info. First I was going from the builders original ad. This is not what I got! The pistons are KB135.040.

That would be this one in a .040" over-bore:
shopping




But the heads are NOT 76CC. I got the casting number from the head which is 14102193, which comes up as a 64 CC head. One of the things that i read is that these may measure out to 65.3. Don't really know, but the manufacturer says 64cc? 14102193...87-up...305/350......1.94"/1.5" valv.
I'm not sure why the shop would select that cylinder head with the smaller int/exh valves for a Marine 6.3L build!

so when I look at the specs on united engine machine for the exact piston, they say 9.7:1 c/r https://www.jegs.com/i/United-Engine-Machine/648/KB135.040/10002/-1. Better than 8.6:
Yes, better than the previous 8.6:1!

We cannot accurately calculate a Static Compression Ratio without all of the "knowns"!
If this piston's dish volume is 18cc, then that is only one of the "knowns".
You will also need to know the piston deck height, compressed head gasket thickness, etc. along with the other data.



These according to what I read were TBI heads, and are not racing heads (Which I am not looking for anyway) better?
We will see SBC cylinder heads in light castings and heaving castings.
You want to avoid the light castings.
These are typically identified by the scalloped areas along the lower side of the casting.
(examples only)

fetch
 
Rick and others reading this thread, I contacted the builder, and after research on their part, they guarantee 9.3 C/R. One thing that I am learning thru this process is that it can be complicated! There is not enough information readily available. I did more research on the heads, and it looks like from the information I have found these heads were a good choice, here is just on of the explanations of these heads that I found:

These heads were made from 1987-99 with 1.94 intake valves and 1.5 exhaust valves. Combustion chamber size is 65CC, which would offer you the ability to get a reasonable compression ratio with flat top or slightly domed pistons. I don't want to say that these heads have good flow characteristic other than they are noted as "swirl port" heads. There are no port volume statistics on them.

Swirl port heads were on trucks and boats mostly. The swirl port design was created to provide good fuel mixing and more swirl pattern as the flow enters the combustion chamber. This improves the fuel burn rate with a more complete combustion resulting in less unburnt fuel in the emissions. The focus here was on emissions but the same rules for port swirl apply to performance engines as well.

If you use these heads for a performance engine and do any modifications to them, I recommend you take them to a professional if you want any port work done. Hopefully they use a flow bench in the process because without incremental testing the swirl characteristics can be diminished.

Keep in mind that these head castings are likely thinner than most performance heads so you're limited on how much mterial you can remove to improve flow. Consider that an old 461 casting from the 60's weighs 47lbs bare (no valves, and rockers). If you weigh each of these heads and they come in less that that, then you are dealing with thinner casting walls.






I think alotta ppl get confused & get #'s twisted around.Ppl read or hear that swirl ports are no good for a high revving strip engine & then translate that into swirl ports are no good for anything.The 193's actually outflow Vortecs up to approx. 3500 rpm,then the Vortecs pass them & keep going.A set of stock 193's will normally run outta breath by 4500.Of course,other factors can vary that by a few 100 rpm. For an average street cruiser in the 300 to 330 HP range,they can be a good budget head.Before Vortecs came about,they were the best production iron head from GM to date,except for LT stuff.

I found this information in several places.
 
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Rick and others reading this thread, I contacted the builder, and after research on their part, they guarantee 9.3 C/R.
Are you not curious as to what Quench dimension are they shooting for?

One thing that I am learning thru this process is that it can be complicated! There is not enough information readily available.
Your shop should have all of the information that they need.
If not, perhaps this is not be the right shop to be building this engine for you!


I did more research on the heads, and it looks like from the information I have found these heads were a good choice, here is just on of the explanations of these heads that I found:

These heads were made from 1987-99 with 1.94 intake valves and 1.5 exhaust valves.
For a 6.3L Marine build, I wonder why the shop would suggest the small intake/exhaust valve diameter!


Combustion chamber size is 65CC, which would offer you the ability to get a reasonable compression ratio with flat top or slightly domed pistons.
Open up an On-Line static compression ratio calculator and plug in your knowns.
Flat top pistons with a 3.750" stroke and with 65cc combustion chambers comes out to be approx 11.4:1, of which is far too great for Marine use!


I don't want to say that these heads have good flow characteristic other than they are noted as "swirl port" heads. There are no port volume statistics on them.
I did some quick research myself.
The
general consensus for the #14102193 is:
.... production start date 1987
.... small valves @ 1.94 and 1.50
.... good for small displacement engine.
.... light casting.

.... good for up to 4,500 RPM only. (you won't be into this RPM range)
.... sometimes mistaken for the 14102183



Swirl port heads were on trucks and boats mostly. The swirl port design was created to provide good fuel mixing and more swirl pattern as the flow enters the combustion chamber. This improves the fuel burn rate with a more complete combustion resulting in less un-burned fuel in the emissions. The focus here was on emissions but the same rules for port swirl apply to performance engines as well.




If you use these heads for a performance engine and do any modifications to them, I recommend you take them to a professional if you want any port work done. Hopefully they use a flow bench in the process because without incremental testing the swirl characteristics can be diminished.

Keep in mind that these head castings are likely thinner than most performance heads so you're limited on how much mterial you can remove to improve flow. Consider that an old 461 casting from the 60's weighs 47lbs bare (no valves, and rockers). If you weigh each of these heads and they come in less that that, then you are dealing with thinner casting walls.


I think alotta ppl get confused & get #'s twisted around. Ppl read or hear that swirl ports are no good for a high revving strip engine & then translate that into swirl ports are no good for anything. The 193's actually outflow Vortecs up to approx. 3500 rpm,then the Vortecs pass them & keep going. A set of stock 193's will normally run outta breath by 4500. Of course, other factors can vary that by a few 100 rpm. For an average street cruiser in the 300 to 330 HP range,they can be a good budget head. Before Vortecs came about, they were the best production iron head from GM to date,except for LT stuff.

I found this information in several places.

I find it interesting that these Hot Rod guys change from one cylinder head to another (as to see what differences they make), but NEVER do you hear them talking about changing piston profile to accommodate the different cylinder head chamber volumes!
 
On the Third Generation hot rod forum, a member responds to a question re; the difference between the 14102187 and 14102193 castings :

The 187s are 305 swirlies, and the 193s are 350 swirlies. I can't imagine either being "better" than the other for anything, although one probably would be worse than the other, in any given application. They even weigh about the same, so their effectiveness in anchoring a boat would be about equal, and you'll get about the same for them at the scrap yard (which is what you need to do with both sets).


Another member says:

[FONT=Verdana, geneva, lucida, lucida grande, arial, helvetica, sans-serif]Although it may appear dim, new light has been shed on swirl port heads. When ported they can produce decent flow numbers for low RPM motors. In stock from the 187's outflow the 416/081's on the exhaust side but do not on the intake side. The jury is still out on which side is better to err on. A few people have flow benched these heads in ported and non ported stages and discussions of each are covered in some of these following threads. The decision is up to you weather or not you want to use them. You will never get the same performance out of a a swirl port head as compared to a properly ported set of 416 or 081 heads. However, when untouched those heads (416's and 081's) are only marginally better. Tuning and cam selection are keys to making power with these heads. Dewey is running 14.5's with his untouched stock 187 heads. You need to choose a cam that works well with the low RPM flow advantages of these heads. Read the following and judge for your self. More and more track data is starting to come up which is changing all previous attitudes on swirl port heads. I was a huge skeptic until I started seeing this data and looking at peoples track times with proper chip tuning. I have not made a formal decision on which heads I would choose for a TBI application. I honestly have been shocked by the results some people are seeing and it is hard to ignore their recorded flow/track time results. If you have no money at all and cannot fully take advantage of a 416/081 head, then the swirl ports can be used. You limit the future potential with swirl port heads when compared to other GM castings. However, if you have a low RPM motor it may be a viable consideration.

[/FONT][FONT=Verdana, geneva, lucida, lucida grande, arial, helvetica, sans-serif]Another member posts: [/FONT][FONT=Verdana, geneva, lucida, lucida grande, arial, helvetica, sans-serif]

[/FONT]they give great torque up to 4500 rpm but die after that.


On the HotRodders forum, I found this:

65.3cc combustion chamber
1.94 intake and 1.50 exhaust
This cylinder head is not a performance oriented cylinder head. It is classified as a high swirl head that was intended for good bottom end torque and fuel economy. The intake runner is restrictive because it has a ramp cast into the bottom of the bowl to promote high swirl.

 
Rick, thanks for sticking in with me. Intrestingly enough I sent the following e mail when I started this trek. this was a copy and paste from here on one of the threads:


hi this might help with what I am trying to accomplish thanks




I am looking at building out an extra 350 I have to a 383. This will upgrade the current 350 I have mated to Volvo dp drive. This is going in a 28' cruiser so I am concerned about detonation.
Your concern is very valid, and is exactly why you will want to steer clear of the GM Full Dished pistons for this build.


The GM style F/D piston cannot possibly create a Q/E (quench effect) within the combustion chamber.
A good Q/E build will greatly reduce the liklihood of Detonation!

It's often a hard sell to those who do not understand it, or who are not willing to educate themselves on it.

And why GM and many rebuilders continue using the Full Dished piston......, is beyond me! :mad:

Size the piston dished volume to complement the volume in the cylinder head chamber, and there ya go!
With the correct piston p/n, this creates no change to C/R and no other mods are necessary!
For a few beans more, it can be done easily and correctly, and we reduce Detonation potential! :cool:


George, as to what we're talking about, you'd have to do a search re; Quench Effect or Squish Effect, and related this to Marine!
It's all about what's occuring underneath the wedge, and the potential for Detonation in our Marine gassers.
The Full Dish piston does a lousy job at this!

See this image, and imagine the dished portion coming up underneath this wedge area.
The outer ring landing comes to within correct "deck" or "Quench" dimension, but dished area cannot!
The dish is OK in the open chamber...... it's coming up under the wedge area that creates the issue.
26603d1139171792-piston-deck-measurement-clearance-squishband.jpg


(in all fairness, I'd have to say that the full dished piston does not necessarily create an issue, as ignition TA is held back considerably to accommodate it's lack of quench ability and to help against detonation potential............ but it sure as HELL doesn't "HELP" this engine any! )

BTW, for the Marine build, the quench or squish dimension can be tightened up some..... DM suggests as tight as .038".



IMO, a good choice for the Vortec chamber may look more like this:

KB735_700pix.gif



The D dished piston works well with the standard Non-Vortec wedge:
 
If you read on further (in that thread), you’ll notice that I made a correction to my verbiage.
I had previously said; “....... it’s coming up underneath the wedge area” ...... when I meant to say “coming up underneath the cylinder head’s quench surface!”

Please see that notation!

.
 
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