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Author Topic: Big Block 400 Stroker Build!!  (Read 13707 times)

Offline PlumCraZRT

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Big Block 400 Stroker Build!!
« on: March 21, 2007 - 06:00:59 PM »
This is a thread I'll probably be posting to for quite sometime (or at least until my stroker project is finished), but I have recently acquired a 73' 400 block with an original 53,XXX miles on it (never rebuilt).  I plan on making it into a stoker and have been looking seriously at the 440source.com stroker kits.  I have looked at what others have had to say about them and I figure if I'm gonna get one I would let my engine builder buy the rings and bearings on his own, and allow him to fit everything together the way it should be.  I understand that on the 400 kits you need to chamfer the edges of the bearings and I have read of some people having issues with tolerances there, so I figure let the builder deal with all of it.  I was wondering what you guys think would be the best kit to go with, either the 512 kit or the 470 kit.  I don't want the 500 kit because it would require oil ring support rails which i have read suck for longterm use.  This engine would be for regular use (not a commuter car, but no trailer queen either) so it should be streetable enough to easily get me to the store and back, drive any day of the week, etc.  I suppose I am asking between the 512 and the 470 because I am concerned with cooling.  This motor is also intended to look identical to the stock 383 I already have in my car, so I don't want electric water pumps/fans etc.  I am using the heavy duty cooling stuff that mopar put on it's big blocks and can't see a better way of cooling without going (noticebly) aftermarket.  I know Chryco Psycho has a lot of experience with performance building so maybe I'm primarily looking to him for support, but anybody that can help, please give me input.

One last addition, I expect the car to run on 91 octane and will likely be going with the Edelbrock heads with the 84cc chambers in order to keep the compression below 10:1 and in order to retain all stock hardware in the head.  I figure with a decent quench I should be fine with anything below 10:1, even with a relatively mild cam that I expect to install to keep the whole thing streetable. (In case you didn't know cams with less overlap will increase you detonation potential, hence my previous comment)  I also want to keep a hydraulic cam and standard stamped rockers if possible to keep down both cost and maintainance.

Anyway, with all that out of the way... what do you all think as far as stroker kit, amount of overbore, head gaskets? 
mmmmm.... Mopar.... *drool*

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Big Block 400 Stroker Build!!
« on: March 21, 2007 - 06:00:59 PM »



Offline 73EStroker

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Re: Big Block 400 Stroker Build!!
« Reply #1 on: March 22, 2007 - 06:30:11 AM »
I am using a 230 casting 71 block with the 440 crank, Eagle Rods, Ross pistons. We haven't dynoed mine yet but are expecting 600HP at the flywheel based on similar setups. Why do you want to go with the longer stroke? CP will tell you the rod ratio is what it is all about and you are heading into Chev Rod Ratio territory. The 451 has mountains of torque and revs like stink. My 2c worth anyway. Also use some real heads like the new Indy EZs if you are going to spend the money. There was an article in Mopar Action about Ehrenberg swapping out some Edelbrocks for Indy EZs (on that 500" 69 RR project) and the difference was immense in favour of the EZs. Something like 50 or 60HP more.

Otherwise the best of luck with whatever you build. It's still Mopar whatever you do.
Barry (Salmon Arm)

Offline Kapteenikosmos

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Re: Big Block 400 Stroker Build!!
« Reply #2 on: March 22, 2007 - 06:51:06 AM »
I have 400 block waiting for the 512cid 440source stroker set when I get time and money to build it so this thread sound interesting. I have heard that we have couple of 512cid strokers here in Finland and the results I have heard, have been very good. Anyone on this board burning tires with that combination?
Ville

1967 six banger Mustang
1973 Challenger (under restoration)
1997 Lincoln Mark VIII LSC (daily driver)

Offline Chryco Psycho

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Re: Big Block 400 Stroker Build!!
« Reply #3 on: March 22, 2007 - 09:42:07 AM »
for long term reliability which you seem to want I would keep the overbore to the minimum to maintain the cylinder wall stiffness , also for long term I would stick with the 451 using the 440 ratios , it wil remove approx 7 lbs from the rotating mass & will rev a lot better than the 440 , with alum heads you can easily be in the 10.5 compression range on pump gas , the biggest I would go is 470 CI especially since you are staying with a hyd cam & not looking to max out the performance in other areas or build a race engine which would be rebuilt every year or 2   

Offline moper

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Re: Big Block 400 Stroker Build!!
« Reply #4 on: March 22, 2007 - 10:12:45 AM »
I'm with CP on this. the longer strokes in the B block will wear themselves out quicker than a combo with a 3.75 or 3.9 stroke. In terms of supplier, if yo uget pistons thru Brandon, make sure the builder knows the ring size (width) is smaller. 440sourcenow sells Total seals. Not my favorite ring,  but a kit is a kit. Same with bearings. If your shop is turning down a 440 crank to make a 451, then they shoudl get teh bearings. If you plan to order the kit, just get Brandon's. You may need to enlarge the chamfer. But you may not. In any case, if your shop uses Cleavite, they will buy the same bearings, and you may have the same issues. So just have them shipped with the kit. ON the compression, if you choose a dished piston, you can run a tighter quench and still be in the 9.8:1 range. So smallish hydraulic cam ( say 235-240@.050 duration, .540ish lift) will run great on pump fuel. The 505 I'm doing has a static of 10.4:1, and should be fine for 87 octane.

Offline PlumCraZRT

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Re: Big Block 400 Stroker Build!!
« Reply #5 on: March 22, 2007 - 10:22:36 AM »
So do you think I should still go with the 440source.com 470 kit?  Or should I get a 440 crank built to my specs to get a 451-470 CI engine?  I am looking for performance, but like what you said, it's not a race engine and i don't plan on rebuilding every 2 years.  I'm hoping to find a low(er) budget build to give me considerable performance over what I have, but the plan is also to maintain a completely stock look (by painting aluminum heads orange, etc.).  I am starting to understand a lot more of the mathematics in getting compression ratios correct and getting correct rod/pistons to match a head/crank combo.  Any other kits you might suggest if I were to go the remachined crank route?  I have read about manley making rods with Chevy 2.200 rod journals and floating .990 pins to be used on a 440 crank offset ground to a 3.90 stroke (which is probably exactly what the 440source kit is).  Maybe thats the way to go?

Basically you guys are saying stay away from huge displacement if I want to keep long term reliability.  To get a true 470 CI I would only need to bore .035 over.  You think that could create reliability issues when 440source's site says you can "go .060" over with 'em all day long"?

Also as far as cams, whats the max lift the stock rockers are good for?  I know the 509 cam was really popular, so I'm assuming people did that with stock hardware (so they must be good to .509 lift), right?

I know, lots of questions.  Thanks for the help all.  You guys rock!!!!! :ylsuper:  You guys are getting me all excited for a stroker!!!   :woohoo:
mmmmm.... Mopar.... *drool*

Offline PlumCraZRT

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Re: Big Block 400 Stroker Build!!
« Reply #6 on: March 22, 2007 - 10:48:19 AM »
Oh yea, and if anyone is interested, I have an excel spreadsheet I have created which will generate compression ratios based on standard engine dimensions (deck height and standard bore), component dimensions (stroke, rods, pistons, head gasket), and modifications (overbore, decking).  Message me with your email address if you are interested.
mmmmm.... Mopar.... *drool*

Offline moper

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Re: Big Block 400 Stroker Build!!
« Reply #7 on: March 22, 2007 - 10:59:38 AM »
Well, there are a bunch of different ways to get things together. For longevity, the 451 makes the most sense to me. I've found over time that unless you are very skilled, and have the right machinery handy, tyring to take the rock bottom price way leads to extra spending in other areas, and the end result costs more than rock bottom, and performs less than stellar. I've built several 451s. the first one was a forged 440 crank core, Eagle rods, and J&E pistons. This was in '98. At that time, 440Source wasnt even a tipsy idea on a cockatil napkin. So you hade either stock parts, or expensive parts. Nothing much in the middle. The last one I did was just before Brandon intruduced the B wedge counterweight cranks with the chevy size rod journals. So that crank needed the counterweights turned down to fit. Now, it doesn't make sense to use a factory crank, unless it's a very basic truck engine. Now, I find his balancing to be not quite as detailed as I want it, so the kit if it was oredered tomorrow would be $1200 plus shipping with no options. I dont like full grooved mains, and I dont like total seal rings very much. So I would order the upgraded C&A rings, and not the full grooved bearings. In any case, it's less than $1400 plus shipping. To turn, polish, and clearance a stock crank, you're looking at $300. Rods, $300 with small ends bushed, and pistons will run $550 for a set of Diamonds. You dont have rings or bearings yet, and you're workling with stock stregth rods and crank. It's smart money to buy the kit IMO. There is a note about chamfering the bearings. You can do it by hand very easy if you're careful and steady. If you are looking for a stock look, the new MP aluminum "452" heads (made by Edelbrock) may be a nicer choice. More $$ by a little, but they will look more factory painted than the milled signature on RPM heads...lol. And they fit with manifolds better. Trust CP and his judgement on over-boring. I bought a good sonic tester, and learned how to use it. Brandon doesnt, and a statement like ".060 over with no problem" is a blanket statement, and not very accurate when you go beyond factory sizes. If you stay with 3.75 stroke, you're basically building a lightweight, compact, 440. Cam it that way. I dont like MP cams. They are not made well anymore, and much better designs are out there. CP likes Engle Cams. Price wise and quality wise, Engle is pretty good. Very good in fact. Typical shelf grinds from Comp would be my next choice. With any shaft rocker (non adjustable) type, your builder will have to check lifter preload very carefully. Because if it's off, you cant fix it easy...lol. I dont think you'll be disapointed, and a 451 will last for years if built right.

Offline PlumCraZRT

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Re: Big Block 400 Stroker Build!!
« Reply #8 on: March 22, 2007 - 11:29:36 AM »
Got an MP part number on those aluminum heads you are talking about?  Is it P4876311?
mmmmm.... Mopar.... *drool*

Offline moper

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Re: Big Block 400 Stroker Build!!
« Reply #9 on: March 22, 2007 - 01:46:42 PM »
P5153524    I havent seen them yet. I have read a little (very little) about the quality control. Expect to have the valve job corrected, and inspect all parts well. Here's a pic...

Offline PlumCraZRT

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Re: Big Block 400 Stroker Build!!
« Reply #10 on: March 22, 2007 - 03:45:45 PM »
Thanks for the info... i looked into the heads a little bit and really see no advantage (besides looks and the spark plug location) to go with the MP heads.  Unless the spark plug location is a serious issue (ie it doesnt work at all) on Mopars with the HP exhaust manifolds, I'll save the $240 and go with Edelbrock.  I suppose even then I am contemplating getting the Schumacher tri-y headers, which would deviate from stock a little bit.  I figure the headers would help loads over the stock manifolds, especially with a stroker and nice flowing heads.  And from what you are saying, I could be saving even more money and likely some headaches if that stuff about the valve jobs being messed up is true.

Anyway... new and improved plan for stroker kit, critique as necessary!

440source 470 stroker kit with -17 cc dish pistons
bore engine .035 over (to 4.375)
deck engine .008" (to zero deck it)
4.380" bore, .020" compressed thickness steel shim head gasket
Edelbrock heads with 84 cc combustion chambers

This combination should yield ~10.1:1 static compression and a really nice quench.
What are your thoughts on the overbore and steel shim head gaskets?  Rip me apart.  I feel like you guys are really teaching me a lot... im happy!  :bigsmile:

Looking for ways to keep compression/displacement high while keepin cost/reliability low!  17cc dish pistons make the compression aspect a little difficult... not exactly ideal dish size.
mmmmm.... Mopar.... *drool*

Offline Chryco Psycho

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Re: Big Block 400 Stroker Build!!
« Reply #11 on: March 23, 2007 - 02:19:40 AM »
Steel shim gaskets may survive OK but the best choice is the Cometic MLS gasket
I would be looking closer to 10,5:1 compression
 if the block has as low miles as you say try to get .010 or .020 pistons
 I doubt the Schumaker headers will seriously outperform the iron manifolds especially for the price , do TTi or port the iron manifolds , & change the cam grind if you use the iron manifolds , the manifolds work better with less overlap in the cam so look for a 112* CL for manifolds
 I am not a fan of the 509 Mopar cam either , there are far better grinds available now 

Offline PlumCraZRT

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Re: Big Block 400 Stroker Build!!
« Reply #12 on: March 23, 2007 - 03:43:21 AM »
Hey Chryco,
I'll look into your suggestions tomorrow/today (its 2:50 am) if i can.  I've heard nothing but the best from Cometic, but at first glance their compression thickness being at .040 is hurting :(.  As you said, I am also striving for a 10.5:1 ratio, but am finding that difficult.  You sure that will work with 91 octane and a mild cam?  I'll also have to look into custom (or at least different) pistons to try what you're saying.  Got a specific cam grind in mind?  I'm not suggesting a 509 cam, but asking what lift is possible with stock hardware.  Lastly, what would porting the exhaust manifolds exactly entail? You suggesting extrude honing them?  How much would that cost?  If it's classic porting, can I do it at home?  How much time would be involved especially related to how much performance gain i can expect?

Again, thanks for the help everyone.  Feel like I'm getting closer and closer to a solution. :burnout:
mmmmm.... Mopar.... *drool*

Offline moper

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Re: Big Block 400 Stroker Build!!
« Reply #13 on: March 23, 2007 - 08:12:23 AM »
Notice I was staying witht he 451 idea? The 470 uses the short  B rod, and has a rod ratio slightly worse than the bigger ones (more wear). So, if you are planning to use a rod ratio in the 1.5-1.6 range anyway, use a 4.25 stroke and make it a 512. (go biggest that you can that also is easy to fit and doesnt use oil ring supports)
Steel shims can be used on aluminum, but shouldn't if at all possible. They will react with the head material, and they will corrode. You are building it from scratch, so you can set things any way you want. Cometics are a good option, and you order them in the thickness you need. I think they go from .018 compressed to as thick as you need. But, they need a VERY smooth surface finish on both block and heads. The finish from Edelbrock is almost too rough out of the box. You can run angle plug heads with manifolds, but you may have issues with the numbers 5 and 6 cylinders IIRC. The issues with quality control are Edelbrock's too. You can run them out of the box. BUt the guys that dont have them checked may not be running as well as they could be. I woudlnt waste any time porting or extrude honing manifolds unless you are in a class that mandates them. If you want the look, accept that they will be the choke point, and cam accordingly. Otherwise, upgrade. Mopar hipo manifolds flow very well for what they are. But that still only means they area a good manifold, not a performance exhaust part.

Offline Chryco Psycho

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Re: Big Block 400 Stroker Build!!
« Reply #14 on: March 23, 2007 - 09:44:42 AM »
I have ported HP manifolds in the past to open up the port to match the head , mostly I have done this to max performance on stock looking engine that some customer want , but as I said the cam has to be carefully chosen to work best with the restrictive manifolds , due to better scavenging with headers you can add more overlap into the cam profile to help cylinder evacuation & filling 
 Alum heads absorb more heat than iron so you can run aprox 1 point more compression on the same fuel with alum heads so 10:5 will be close to 9.5 with iron heads  I use a lot of the Engle cam grinds when using Hyd cams with great results , the duration is less with the engles but generally with as much or more lift than the .509 Mopar cam
www.englecams.com

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Re: Big Block 400 Stroker Build!!
« Reply #14 on: March 23, 2007 - 09:44:42 AM »