Can you guys rate my 383 build...

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I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

In a perfect world the flame front would progress faster across a flat piston than one w hills but a flattop piston w enough CH to get quench will most likely give you too high of CR plus you'll need valve reliefs machined. Get the KB's w the quench plateau & mockup/machine to get quench (.040" max) plus the right SCR for your app

The thing is the dome isn't on the side where quench is obtained, it's in the chamber area... To get quench you need a closed chamber head which I believe is what the O/P is planning to run... So at the point quench becomes a function of how far the piston is in the hole & head gasket selection.... There are no off the shelf quench dome pistons for 383's...

Exactly.

I know what you guys are saying about the flame travel....what I'm trying to understand is what does that mean in terms of performance? JohnRR mentioned he wished he would have cut the heads instead of using the dome.....what do you cuss about when driving your car that you think to yourself "I wish I would have cut the heads.."

I fully understand what quench is and the benefits. I also hear from you guys that the aluminum allows for a higher CR because of the reduced heat inside the chamber. @ 10:1 CR, do I need "perfect" quench when I'm using heads that supposedly give me the same effect as a 9-9.5:1 steel headed engine when I already plan on running 93 octane? In other words, with the reduced heat that you guys mention, will quench really play that much into any detonating problems @ 10:1 with aluminum heads.

Posted By: ireland383

Re: Can you guys rate my 383 build... - 03/29/11 02:28 PM

The RB block is slightly wider making clearance of the starter easier. I have Hedmans and my mini starter just touches one of the tubes. Been on there for two years and hasn't burnt up yet.

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/29/11 02:29 PM

Don't know the brand of headers but they didn't have a flat spot till I beat one in it because it was resting against the stock factory starter , which probably explains why the car ate a starter so quick . I bought the car with the headers on it , the person that screwed it together obviously was not paying attention ...

Posted By: Mr.Yuck

Re: Can you guys rate my 383 build... - 03/29/11 02:35 PM

this one has plenty of room. I ran Hedmans as well on my old 383 charger..no issues and this was before the mini was available. I also had a set of black-jacks on a 68 383 bee. no issues w/ those either. the Summit look just like the headmans

Posted By: gch

Re: Can you guys rate my 383 build... - 03/29/11 03:06 PM

You can mill the heads to get the compression up if so desired.

You can also advance the cam 2-4 degrees from the recommended setting if you are worried about your bottom end(this will build cylinder pressure also).

The carb is too small but it will run find.The power drop off will show up in the upper midrange and top end.It will help the low bottom end slightly this way.

Posted By: BSB67

Re: Can you guys rate my 383 build... - 03/30/11 01:26 AM

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Ok, I have parts, so this is pretty much the way the build is going to be, not much in the room of changing things around now...

I did as much research as I could....with the help of you guys

Anything with a "?" beside it is still not for sure...so I would need some input

383
.030 over
std rod/mains
ARP rod/main/head bolts
Edelbrock closed chamber heads
Cometic .027"/4.35" head gaskets (?)
SpeedPro 2315 (1.920" CH)
stock deck height (squared to crank)
balanced assembly
Comp XE 274/286 cam/lifters
Performer RPM intake
650 Thunder Series Carb (?)
MP igniton conversion kit
Factory HP manifolds (?....any issue with the angled plug heads? would rather not use headers)
Comp Double Roller

I'm getting 9.57:1 CR ASSuming the piston is .01 in the hole with the 2315 pistons. That would also figure a .037" quench as well....correct?

How does this sound to you guys?

MP has the Eddy head in a straight plug, but it looks like you've purchased the heads already.

Get the CR to 10:1 to 10.2:1

I too prefer zero deck and a 0.040" gasket. You'll probably save $ on the gasket too.

I too like the Crower 271 cam.

I would use more carb cfm

You definately do not need 3" exhaust. It will probably hurt performance.

Posted By: DartGTS

Re: Can you guys rate my 383 build... - 03/30/11 02:21 AM

Hello:
Lots of different opinions here, I'm not going to touch engine build.. best thing you can do for street performnce with that car is replace that 3:23 with a taller gear.... 3:91 (and convertor to match) if you don't do lots of highway interstate driving. That 3:23 gear with big cam not gonna be best stop light car.

My 2 cents.
Maynard

Posted By: JoesMopar

Re: Can you guys rate my 383 build... - 03/30/11 03:00 AM

Ok, I am not building a race car, drag car etc. I am purposely building this thing to cruise, especially the interstate and highways. I appreciate the info on swapping converters, gears etc. But I'm not going to do that, it is what it is and I did it for a reason....I already have a car with a 3200 converter and "only" 3.55's. It revs too high on the interstate as it is....3200 RPM is too noisy for my liking.

My main concern is the heads/piston/head gasket combo. I wasn't aware when building a 383 that piston choices suck. Not only that, but it sounds like my options are expensive pistons or expensive machine work. I just so happen to have the expensive pistons....however from what most people on here tell me that the CR will not be enough with my head gasket choice (if I get it....027") and my head chamber volume (84cc). So I am back to thinking of just ordering a set of KB400s which from what I have calculated should be very close to 10:1...but I could be and probably am wrong.

Once I get info from the machine shop of what the depth will be with the KB400's vs the 2315's I'll make a definitive decision. Supposedly the KB400's will be inefficient compared to the flat top 2315's.....whatever that means.

The gear stays, the converter stays, the cam stays....I will probably take everyone's advice on the carb, maybe even consider headers after I get some miles on it and feel like doing something.

Posted By: 71383beep

Re: Can you guys rate my 383 build... - 03/30/11 03:31 AM

if your looking for just a cruiser the eddy heads are a bit overkill. You can get decent street manners of a similar setup with OE closed chamber heads like the 516 or better yet the 915 heads. I have 516's on mine with a bigger exhaust valve and the mopar .474 cam. With KB162s and some head work it is 9.2:1.

Also running a 650 mighty demon and the car moves rather nicely for a 3,800 purple beast. I don't care for the edelbrock carbs personally.

Posted By: Mr.Yuck

Re: Can you guys rate my 383 build... - 03/30/11 12:18 PM

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Ok, I am not building a race car, drag car etc. I am purposely building this thing to cruise, especially the interstate and highways. I appreciate the info on swapping converters, gears etc. But I'm not going to do that, it is what it is and I did it for a reason....I already have a car with a 3200 converter and "only" 3.55's. It revs too high on the interstate as it is....3200 RPM is too noisy for my liking.

My main concern is the heads/piston/head gasket combo. I wasn't aware when building a 383 that piston choices suck. Not only that, but it sounds like my options are expensive pistons or expensive machine work. I just so happen to have the expensive pistons....however from what most people on here tell me that the CR will not be enough with my head gasket choice (if I get it....027") and my head chamber volume (84cc). So I am back to thinking of just ordering a set of KB400s which from what I have calculated should be very close to 10:1...but I could be and probably am wrong.

Once I get info from the machine shop of what the depth will be with the KB400's vs the 2315's I'll make a definitive decision. Supposedly the KB400's will be inefficient compared to the flat top 2315's.....whatever that means.

The gear stays, the converter stays, the cam stays....I will probably take everyone's advice on the carb, maybe even consider headers after I get some miles on it and feel like doing something.

if you are worried about compression use the steel shim gasket. IIRC it crushes to .019. If overall performance isn't an issue Grab a $70 summit cam and toss the thing together. It will run fine.

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/30/11 01:42 PM

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Ok, I am not building a race car, drag car etc. I am purposely building this thing to cruise, especially the interstate and highways. I appreciate the info on swapping converters, gears etc. But I'm not going to do that, it is what it is and I did it for a reason....I already have a car with a 3200 converter and "only" 3.55's. It revs too high on the interstate as it is....3200 RPM is too noisy for my liking.

My main concern is the heads/piston/head gasket combo. I wasn't aware when building a 383 that piston choices suck. Not only that, but it sounds like my options are expensive pistons or expensive machine work. I just so happen to have the expensive pistons....however from what most people on here tell me that the CR will not be enough with my head gasket choice (if I get it....027") and my head chamber volume (84cc). So I am back to thinking of just ordering a set of KB400s which from what I have calculated should be very close to 10:1...but I could be and probably am wrong.

Once I get info from the machine shop of what the depth will be with the KB400's vs the 2315's I'll make a definitive decision. Supposedly the KB400's will be inefficient compared to the flat top 2315's.....whatever that means.

The gear stays, the converter stays, the cam stays....I will probably take everyone's advice on the carb, maybe even consider headers after I get some miles on it and feel like doing something.

The CH of the KB400 is 1.908 , the CH of the 2315 is 1.920.

You should really call the cam company and get their recommendation for the convertor a cam/rear gear mismatch can be somewhat masked by a 4spd , not some much with a automatic trans. ... edit , I just went back and reread, your convertor choice may not be that far off especially if you go with the 268.

What I meant by inefficient is the dome impedes flame travel across the chamber , a flat top doesn't . I am building a 383 based stroker with 12.5 compression and the only way to do it was either cut the bleep out of the heads or use a small dome , I chose the dome , should have cut the heads

You didn't buy the EXPENSIVE piston , that is the Diamond. You could have had the block decked , mock it up and ordered a piston that didn't require cutting a mile off the block, that's what I did with the 383 engine that I just recieved from the shop yesterday. But my block had already been cut a mile because of bad first piston choice, the 2315, and then shoddy machining by a couple of shops this block has passed thru till the latest. It's a 10.0 build with open chamber iron heads.

Do what you want , you asked for people to rate your build , you got it and it seems you don't like some of the answers you are being given.

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if you are worried about compression use the steel shim gasket. IIRC it crushes to .019.

The steel shim gasket is .021, 65-75 ft/lbs is not going to crush it like it does with a composite gasket .

Posted By: JoesMopar

Re: Can you guys rate my 383 build... - 03/31/11 02:28 AM

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The CH of the KB400 is 1.908 , the CH of the 2315 is 1.920.

What I meant by inefficient is the dome impedes flame travel across the chamber , a flat top doesn't . I am building a 383 based stroker with 12.5 compression and the only way to do it was either cut the bleep out of the heads or use a small dome , I chose the dome , should have cut the heads

What is the CH of a stock 383 piston? I can't remember but I thought it was less than the KB400 1.908.

I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

Posted By: RapidRobert

Re: Can you guys rate my 383 build... - 03/31/11 02:47 AM

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I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

In a perfect world the flame front would progress faster across a flat piston than one w hills but a flattop piston w enough CH to get quench will most likely give you too high of CR plus you'll need valve reliefs machined. Get the KB's w the quench plateau & mockup/machine to get quench (.040" max) plus the right SCR for your app

Posted By: 1_WILD_RT

Re: Can you guys rate my 383 build... - 03/31/11 03:03 AM

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I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

In a perfect world the flame front would progress faster across a flat piston than one w hills but a flattop piston w enough CH to get quench will most likely give you too high of CR plus you'll need valve reliefs machined. Get the KB's w the quench plateau & mockup/machine to get quench (.040" max) plus the right SCR for your app

The thing is the dome isn't on the side where quench is obtained, it's in the chamber area... To get quench you need a closed chamber head which I believe is what the O/P is planning to run... So at the point quench becomes a function of how far the piston is in the hole & head gasket selection.... There are no off the shelf quench dome pistons for 383's...

Posted By: repad

Re: Can you guys rate my 383 build... - 03/31/11 04:13 AM

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Ok, I am not building a race car, drag car etc. I am purposely building this thing to cruise, especially the interstate and highways. I appreciate the info on swapping converters, gears etc. But I'm not going to do that, it is what it is and I did it for a reason....I already have a car with a 3200 converter and "only" 3.55's. It revs too high on the interstate as it is....3200 RPM is too noisy for my liking.

My main concern is the heads/piston/head gasket combo. I wasn't aware when building a 383 that piston choices suck. Not only that, but it sounds like my options are expensive pistons or expensive machine work. I just so happen to have the expensive pistons....however from what most people on here tell me that the CR will not be enough with my head gasket choice (if I get it....027") and my head chamber volume (84cc). So I am back to thinking of just ordering a set of KB400s which from what I have calculated should be very close to 10:1...but I could be and probably am wrong.

Once I get info from the machine shop of what the depth will be with the KB400's vs the 2315's I'll make a definitive decision. Supposedly the KB400's will be inefficient compared to the flat top 2315's.....whatever that means.

The gear stays, the converter stays, the cam stays....I will probably take everyone's advice on the carb, maybe even consider headers after I get some miles on it and feel like doing something.

Just want to share this with you, last year I rebuilt a numbers 69hp 383 for a super bee. I left it as much stock as the available parts would allow using the speed pro pistons .030 and the Summit cam/lifters which was very close to the original stock hp cam. Even used the original 625 carter carb and the hp manifolds. Stock original converter and 323 gears. Stock original 906 heads with stock valve sizes and springs. This is a sweet running engine with plenty of torque to light up the tires and a respictable high end. The idle is smooth and throttle response is crisp, just a great running engine for the street. To sum it up, the stock hp 383 is a respectable performance engine in its own right. I suggest a pair of headders for a nice 15-20 hp gain.

Posted By: lokalik

Re: Can you guys rate my 383 build... - 03/31/11 04:26 AM

like i said earlier. you won't know anything about cr until you get the block back. it sounds like you are miss matching parts. like the post above said " wish i'd done this or that" think this through and later on you will be much happier. i would not use a dome piston, build in quench, match the parts and you will love how it runs. i would not use a steel shim head gasket w/alum heads. i would recommend studs and not bolts on the heads and use plenty of thread sealer. remember you ask for a review of your build and everyone has as input just like me. keep asking even if you don't like what you are hearing.

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/31/11 04:29 AM

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I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

In a perfect world the flame front would progress faster across a flat piston than one w hills but a flattop piston w enough CH to get quench will most likely give you too high of CR plus you'll need valve reliefs machined. Get the KB's w the quench plateau & mockup/machine to get quench (.040" max) plus the right SCR for your app

Robert , Robert , Robert , you appear to know NOTHING about 383's , you should sit back and LEARN from those that do ...

KB does NOT make a quench head piston for a 383 , never has and probably never will, so you need to stop suggesting that to people building 383's. Nevermind to get quench with a flat top and a closed chamber ... uuum , just zero deck , you zero deck and with 80cc head you end up with 10.0 , since the heads he wants to use are 84cc he's not going to have too high a compression ratio ??? It's not rocket science , the problem with a 383 and compression is the SMALL bore size and the SHORT stroke, combined it's hard to get decent compression.

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/31/11 04:38 AM

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The CH of the KB400 is 1.908 , the CH of the 2315 is 1.920.

What I meant by inefficient is the dome impedes flame travel across the chamber , a flat top doesn't . I am building a 383 based stroker with 12.5 compression and the only way to do it was either cut the bleep out of the heads or use a small dome , I chose the dome , should have cut the heads

What is the CH of a stock 383 piston? I can't remember but I thought it was less than the KB400 1.908.

I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

Depends on the year engine but the stock CH of the 68-69 383 HP (which is what i base all my

on ) , and 68-69 2bbl for that matter , is 1.932 , this puts the piston .0025 in the hole on a factory deck height, the 2bbl piston has a dish. as delivered the HP was 9.2 at best. I've gone 100mph in the 1/4 with a 56K worn HP engine with a timing chain so loose it could be removed without taking off the gears ... almost... so it's not as bad as we are lead to believe.

One of the mags did an article on installing ebrocks on a 383 , they THOUGHT they had a piston close to factory CH. But when they pulled the heads it had low compression cast replacements, they were something like .050 plus below the deck , the engine was not the DOG they thought it would be, food for thought .

In the grand scheme of things you will probably not notice any difference with the KB400 so just ignore what I said about inefficiency .

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/31/11 04:41 AM

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i would recommend studs and not bolts on the heads and use plenty of thread sealer. r

Thread sealer on what ? The head bolts on a big block mopar are DRY ????

Posted By: DartGTS

Re: Can you guys rate my 383 build... - 03/31/11 12:24 PM

Hello:
Two points here and then i'm done.
1. DO not use steel gaskets with aluminum heads.
There will over time be a corrosive effect of the dissimmilar metals. How long of time and to what extent is unknown. But since you concerned with street reliabilty why chance anything.
2. Why use Studs instead of head bolts on a mild street engine? Perhaps i'm missing something here, but its seems to be overkill to me. Not sure what car this is going into and perhaps some one else has experience on this with B bodies. But a big block in a A body with studs makes the heads almost impossible to remove with engine in the car. Rember you now have to lift the heads off the studs. That means pulling the heads toward inner fenders, master cylinder, etc 5 or 6 inches. Voice of been there done that.

Anyway good luck with your project hope it works out for you.

Maynard

Posted By: lokalik

Re: Can you guys rate my 383 build... - 03/31/11 12:46 PM

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i would recommend studs and not bolts on the heads and use plenty of thread sealer. r

Thread sealer on what ? The head bolts on a big block mopar are DRY ????

sorry, for the block

Posted By: Mr.Yuck

Re: Can you guys rate my 383 build... - 03/31/11 01:30 PM

you guys are all over-thinking this. It's a friggin' driver 383. Use what you have except the cam. If you haven't bought the e-heads Don't. They are overkill. Grab a summit cam and a good set of used iron heads and roll. You are going to use mani's anyway. You won't be able to tell the difference. Quench? really? On a 330-350 hp motor? who cares. It will run fine. Jeeeesh some people like to make this way to technical. Plenty of toss together 383's and 440's running fine w/ many many miles and many many passes with little or no attention to all those details.
Don't know what the guy is saying about thread sealer on your head bolts...you coat them with oil and put them in. If you run e-heads the studs are better. You do however need to run sealer on your mani' studs. I use teflon tape on mine. Good luck with the build.

Posted By: mikemee1331

Re: Can you guys rate my 383 build... - 03/31/11 01:40 PM

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you guys are all over-thinking this. It's a friggin' driver 383.

bigger carb and headers if you feel like spending the money now and go have fun!

Posted By: lokalik

Re: Can you guys rate my 383 build... - 03/31/11 02:04 PM

thread sealer better than oil.

Posted By: Mr.Yuck

Re: Can you guys rate my 383 build... - 03/31/11 02:19 PM

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thread sealer better than oil.

on a head bolt?

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/31/11 02:47 PM

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you guys are all over-thinking this. It's a friggin' driver 383. Use what you have except the cam. If you haven't bought the e-heads Don't. They are overkill. Grab a summit cam and a good set of used iron heads and roll. You are going to use mani's anyway. You won't be able to tell the difference. Quench? really? On a 330-350 hp motor? who cares. It will run fine. Jeeeesh some people like to make this way to technical. Plenty of toss together 383's and 440's running fine w/ many many miles and many many passes with little or no attention to all those details.
Don't know what the guy is saying about thread sealer on your head bolts...you coat them with oil and put them in. If you run e-heads the studs are better. You do however need to run sealer on your mani' studs. I use teflon tape on mine. Good luck with the build.

Wait , aren't you the guy always spouting off about running a holley and headers for max hp out of any given combo ? Make you your mind .

And on to the sealer on exh studs ... Not on Eheads , only heads from Chrysler directly have wet bolt holes on the exhaust.

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/31/11 02:48 PM

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thread sealer better than oil.

WHY , there is NO WATER on big block head bolt holes , the holes are BLIND, sealer just makes a mess and is a waste of sealer.

Posted By: Mr.Yuck

Re: Can you guys rate my 383 build... - 03/31/11 02:58 PM

"Wait , aren't you the guy always spouting off about running a holley and headers for max hp out of any given combo ? Make you your mind .

And on to the sealer on exh studs ... Not on Eheads , only heads from Chrysler directly have wet bolt holes on the exhaust".

Well if it was mine I'd have a holley and headers, but it's not. So run it his way. Wasn't sure about the e-heads, but some anti-seeze might be in order.

Posted By: JohnRR

Re: Can you guys rate my 383 build... - 03/31/11 07:01 PM

A definite yes on the antisieze ...

Posted By: JoesMopar

Re: Can you guys rate my 383 build... - 04/01/11 03:02 AM

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Quote:

Ok, I am not building a race car, drag car etc. I am purposely building this thing to cruise, especially the interstate and highways. I appreciate the info on swapping converters, gears etc. But I'm not going to do that, it is what it is and I did it for a reason....I already have a car with a 3200 converter and "only" 3.55's. It revs too high on the interstate as it is....3200 RPM is too noisy for my liking.

My main concern is the heads/piston/head gasket combo. I wasn't aware when building a 383 that piston choices suck. Not only that, but it sounds like my options are expensive pistons or expensive machine work. I just so happen to have the expensive pistons....however from what most people on here tell me that the CR will not be enough with my head gasket choice (if I get it....027") and my head chamber volume (84cc). So I am back to thinking of just ordering a set of KB400s which from what I have calculated should be very close to 10:1...but I could be and probably am wrong.

Once I get info from the machine shop of what the depth will be with the KB400's vs the 2315's I'll make a definitive decision. Supposedly the KB400's will be inefficient compared to the flat top 2315's.....whatever that means.

The gear stays, the converter stays, the cam stays....I will probably take everyone's advice on the carb, maybe even consider headers after I get some miles on it and feel like doing something.

Just want to share this with you, last year I rebuilt a numbers 69hp 383 for a super bee. I left it as much stock as the available parts would allow using the speed pro pistons .030 and the Summit cam/lifters which was very close to the original stock hp cam. Even used the original 625 carter carb and the hp manifolds. Stock original converter and 323 gears. Stock original 906 heads with stock valve sizes and springs. This is a sweet running engine with plenty of torque to light up the tires and a respictable high end. The idle is smooth and throttle response is crisp, just a great running engine for the street. To sum it up, the stock hp 383 is a respectable performance engine in its own right. I suggest a pair of headders for a nice 15-20 hp gain.

You have no idea how much I appreciate this information. It makes me feel alot better about the one I'm building. Thank you

Posted By: JoesMopar

Re: Can you guys rate my 383 build... - 04/01/11 03:15 AM

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Quote:

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The CH of the KB400 is 1.908 , the CH of the 2315 is 1.920.

What I meant by inefficient is the dome impedes flame travel across the chamber , a flat top doesn't . I am building a 383 based stroker with 12.5 compression and the only way to do it was either cut the bleep out of the heads or use a small dome , I chose the dome , should have cut the heads

What is the CH of a stock 383 piston? I can't remember but I thought it was less than the KB400 1.908.

I understand what you mean by the dome "getting in the way"....but how does that affect your car? Decreased performance? Gas Mileage? I was looking at getting the dome to help with CR since everyone was saying 9.5:1 wasn't enough for that cam. The dome would put it about 10:1.

Depends on the year engine but the stock CH of the 68-69 383 HP (which is what i base all my on ) , and 68-69 2bbl for that matter , is 1.932 , this puts the piston .0025 in the hole on a factory deck height, the 2bbl piston has a dish. as delivered the HP was 9.2 at best. I've gone 100mph in the 1/4 with a 56K worn HP engine with a timing chain so loose it could be removed without taking off the gears ... almost... so it's not as bad as we are lead to believe.

One of the mags did an article on installing ebrocks on a 383 , they THOUGHT they had a piston close to factory CH. But when they pulled the heads it had low compression cast replacements, they were something like .050 plus below the deck , the engine was not the DOG they thought it would be, food for thought .

In the grand scheme of things you will probably not notice any difference with the KB400 so just ignore what I said about inefficiency .

Thanks for this info

Ok, this is my final plan from the best I can tell from the input on here and what's available to me in the real world...

1) The cam: I am going to save the XE 274 for a future 440.

2) I am going to buy an XE268...will this work with the 3.23's AND 2500 stall? 9.5-10:1 CR ok with this cam?

3) I did some calculations....I looked up the stock deck height (this engine was never apart either) I got 9.98 IIRC. I took the rod length + the SpeedPro's CH of 1.920 + HALF of the 3.375 stroke, subtracted from the favtory deck height spec and....from my calculations.. am ASSuming the 2315 pistons to be .0145 in the hole. So...I think I will use these pistons AND chop .010" off the block...AND machine the intake to fit...if need be...then I'll do a mock up on one cylinder to check valve clearance.

4) I am going with the .039" head gasket...not the steel shim.

5) What would work better for a carb...the 650 or 750 Edelbrock Thunder Series now that I am giving in and going with the smaller cam?

I know how to assemble the main/head bolts....just never did a 383...and probably never will again

Can you guys rate my 383 build...