496 stroker build

[-83MONTESS-]

I just ordered my Scat 496 stroker rotating assembly yesterday for my upcoming winter build. This is my first high performance build so im trying to do all my research to get the best possible setup when the time comes. Im on a budget and I dont need a 10 second car so aluminum heads are out of the question. My goals for this engine is a fun cruiser with hopefully 500-525hp. I dont have any experience with big blocks so im not sure if thats attainable with the build im planning. The specs im looking at right now are:

Cast 4.25" Scat stroker crank
4340 forged 6.385" H-beam rods
.060" over 18cc dome forged Probe pistons (should be between 9.7-10:1 CR depending on what the heads cc at)
122?cc open chamber 049 large oval castings
2.19" intake---1.88" exhaust valves
1.7:1 full roller Harland Sharp rockers
MSD 6AL distributor with the 6AL box
Still undecided on the cam but im looking at these two unless I get a custom grind from Lunati
http://www.summitracing.com/parts/ISK-396281/
http://www.summitracing.com/parts/HRS-121181-08/
I want a hydraulic flat tappet 108 LCA, the lift and duration im not decided on yet. My dad has always had great luck with Lunati so I wanted to go with them but they dont offer a hydraulic flat tappet with a 108 LCA for the BBC. I will use the lifters and springs that are recomended from the camshaft manufacturer.
I know this isnt everything I need but its a start. This will be a slower build until winter hits so I can actually get started. Any advice/info/opinions are welcome so feel free to tell me what you would and wouldnt do 😀

 

[larryo454]

Hi BBC down fall is the valvetrain gear.If using stock iron head put bronze valve guides in and SS valves,The iron guide with the stock valve sticks,and the piston kiss the valve and cracks the steam.GOOD BYE piston,head,and block.
Now i think the cams you got picked out is going to be very mild in a 496.The more cubes the more cam it can handle If you was building a 396 id say go for it with them cams.But the 396 engine is going to be a stout small cube BBC.I run a 600 lift cam in my 461BBC on the street and it has a good lope and don't take long to sing if i want it too.

But i hope you have fun building your 496, and just match your cam gear using proper valve spring and seat lbs.i'd hate to find out you lost it over stock pushrods or stock valves. (BBC stock valve gear is JUNK)

 

[-83MONTESS-]

What cam do you recomend? This isnt gonna be a high RPM engine maybe 6000rpm at the most. All the bigger lift cams I see are 3500rpm and up.

 

[larryo454]

It all in a combo like what converter and trans? or is this going to match what ever engine you do? This is a nice cam it pull very had around 3500rpm in a smaller BBC.your looking to dur @.050 to be 240+ in my 461bbc my dur @.050 is 268.

http://www.ebay.com/itm/COMP-CAM-BBC-CH ... 82&vxp=mtr

 

[-83MONTESS-]

It all in a combo like what converter and trans? or is this going to match what ever engine you do? This is a nice cam it pull very had around 3500rpm in a smaller BBC.

http://www.ebay.com/itm/COMP-CAM-BBC-CH ... 82&vxp=mtr

Im building a 496 not a 396-427-454, so if it pulls at say 3500rpm in a "small" big block what does that mean for my 496? The trans will be a built 700r4 or 2004r and the rear has 3.73s but I want to change to 3.90s. My compression ratio will be between 9.7 and 10:1. The converter I will get after I get the cam. All the .600+ lift cams I see need a 10.25+ CR and have a higher powerband. Also the cam I get will be hydraulic flat tappet not a roller or mechanical flat tappet

 

[larryo454]

Don't get me wrong bud,but just from what i have built and run in BBC i know the more cubed engine more cam is needed to perforum like a smaller cube engine.I know with the cams you got picked out are not bad and can work to some dreg.Just think of it this way a (sponge) the larger it is the more water it can soak up big cubs does the same with dur @ .050
I just don't think your going to hit the 500 to 550hp ##s but your going to pull good TORQUE.

 

[GuysMonteSS]

Maybe a custom grind should be on your list.Talk to someone that really knows what they are talking about,Chris Straub is one of those;
http://www.straubtechnologies.com/
last time I rebuilt my bbc I got a custom solid roller grind from UDHarold,I'll never buy an off the shelf grind again.Heres some info from Harold;


Everyone,

Now I've done it........
I am now selling ALL of my previous work from 1980 til now, and into the future.
If you want an original UltraDyne, or one of my Lunati or VooDoo cams, or one of my Custom Camshaft Rollers, or what I may be doing in the future, please give me a call.
I will be getting a new phone number by the first of January, but my home phone number is still 662-562-4933.
I was a little late getting back from PRI, my son had scheduled impacted wisdom teeth surgery for Monday morning, and wanted me to be his designated driver, so I ended up staying a couple of extra days down there.
Unfortunately, I saw very little of the show, as most of my time was spent discussing 'deals' with cam companies.
Most of the valve train components will be from Lunati, as they have the good Morel lifters, including micro-polished ones, and with oil holes on the faces, and the Pacalloy springs, including the BeeHives.....

If I made it, I sell it.

UDHarold

PS---New designs are being worked on.


This is a few years old,but,AFAIK,Harold still has the same phone #.
Guy

 

[-83MONTESS-]

I got my 496 stroker assembly finally. It was funny watching the old man from fedex trying to carry all of the packages considering the crank weighs 70 lbs :lol: I got a few pics so far but I am extremely happy with it. I will be ordering most of my other parts through Skip White. I have all the balance and blueprint sheets and the crank and rods have already been oiled so I dont have to go through that mess for storage. Anyways heres some pics.

 

[Bar50]

Here is an idea for your 496, look at some of the crate engines that many parts suppliers offer, like Jeg's or Summit, see what cam profiles they offer in the 496's they sell.

The BBC takes a bigger breath, great choice pump gas 496 with good big oval port heads, make for an awesome combo. The increased stroke makes the engine take a deeper breath than the 4 inch stroke 454.

Steel/iron guides are just fine (I've never had any issues even in solid roller set ups) .

Call a few cam companies and see what they reccomend, they want you to be happy. Lots of BBC cams seem to hover around 110 LCA.

I mean, there is not a magic 496 cam, there is a happy medium, sound, idle, torque, hp, the stall you have/need/want. A local guy has one similar to yours in a square body shortwide, he really likes the Edelbrock Performer RPM cam in his, he has since really woke it up with some nitrous.

 

[-83MONTESS-]

Thanks for all the info. Im gonna wait on the cam until after I get the heads done. I do have a question though, can anyone give me a good estimate on getting new guides installed and to have new seats put in and cut for oversized 2.19/1.88" valves? The heads dont need milled or cleaned. I wanna get an idea of what price im looking at because it will be a few weeks before I can make it to a machine shop.