pauldana

Well, as many may know here, I busted the crank in the 383.... Now, I was going to just put in another crank and call it good........ Then Gkull said why don't you go a 396??? and I thought... yea,,, that would be cool.... and then I thought, why not just take the plunge and go a 427... I mean the only thing different I would have to buy would be a block?!?!!?

So... here i am, searching for the best bang for the buck....

Now, I think I have tentatively settled on a Calis rotating assembly, all forged so if I ever want to I can shoot 150 nos... I need the engine to hold good at 800HP.... but im open....

my old cam 243° / 241°@50 .6" / .6"lift 112° ls

I was told that with a bigger bottom end the cam would have to be changed to feel and work the same?!?!?! I would like someone the explain this to me and what would be an equivalent cam to above but for a 427?

What block would you choose? a Dart? or a World? other? why?

any and all input would be appreciated.








NEW ENGINE SPECS 650HP

My 427 build from the bottom up:
Dart SHP block
Milodon 7qt road race oil pan
Milodon diamond stripper windage tray
Calis Dragon Slayer Crank
Skat H-beam's
Probe racing pistons 11:1 forged
AFR competition ported 220 heads w/titanium keepers and locks
AFR plastic single plain titan intake manifold
EZ EFI 2.0 fuel injection system..
MSD full ignition with crank trigger
Kooks 1 7/8 ceramic headers
3" duel mandrel bend exhaust with X-pipe custom made by D&C design... my son Danny:-)
Borla mufflers
march pulley system
22 lb steel billet flywheel
McCloud twin disk clutch
Fluidamper 6 1/4" HB
Custom Cold Air Intake by me:-) D&C design
Custom cam by Strub 611/592 244/248 109 Sep
Morel reto hydraulic lifters
Crain gold race RR's
TKO 600 transmission
SUPER 10 rear end built by trackdog2
18" custom built 2 piece centerline wheels
Willwood big brake system all around
hydroboost braking
rac-n-pinion steering
550 springs up front, 360 composite in back with all Bilstin sport shocks and front and rear sway bars
3" HD Dewitts radiator
DELTA PAG brushless fan w/D&C custom fan shroud
Dewitts 3" heavy duty radiator

gkull

Probably about 10 degrees and a corresponding increase in the heads CFM of flow.

I've ask other 427 small block guys what they are running and it is always in the 248 - 256 intake range for roller cams.


Or just run everything from the 383 and you would end up with the same HP at 800 rpm less with and addition 60-70 pounds of TQ.

pauldana

I would like my operating RPM range to be between 1000/1500-6500/7000 like it is now..do not want to see over 7kRPM. And while the extra tq will be great, I also want to increase in HP.

427Hotrod

The Dart is a nice piece for sure. You might consider just getting an assembled shortblock from them and then picking heads from their lineup. I've done a 400" assembly based on one of their shortblocks and it's done great.

You had a reverse pattern cam before?? That's an odd one for a N/A combo.

Pick the cam AFTER you select heads...need to get it all to work together.

Don't go too small on the heads...I'd be looking in the 230+cc range.

JIM

pauldana

Already have heads... flow is over 300 at .6 lift. 64cc chambers

not sure what your calling out

Crepitus

most split pattern cams have more duration on the exhaust side

gkull

More intake duration than exhaust.

cv67

Got a Comp billet solid roller with 60 mi on it cast gear std base cir
250/254 280/286 110 lsa with 1.6 rocker 660+- lift gross *would have to check*....if i was smart id put this in the 383 but Im not smart.

Think it would work good for yours....very driveable

pauldana

Thx, I thought that is what it meant, but I was not sure... thx again..

then the question for that is, why? Why is it odd to see a reverse split pattern cam?

pauldana

im sticking with my hydraulic retro, do not want to go solid, I spin to 7kRPM with this setup and never float, and I do not want to go beyond, or very much beyond 7krpm.

I have the ultra pro magnum SS Comp Cams 1.52's, when you change up from the stock 1.5's to anything greater...........like a 1.6, this in effect not only changes your valve lift, it also effects a change in your duration.

cv67

for some reason thought you were running a solid oops!
Should be able to make a solid 550+- with a HR these guys are saying and tons of torque .

donyue

Hi pauldana,

My engine was built with a Dart SHP block and Dart Pro 1 -215 heads. The engine builder used a Howards retro-hydraulic roller cam and roller rockers. For the money I am very happy with the engine. I think the only thing I might have upgraded if I had a choice and money was not a consideration would be maybe the Dart Little M block and the use of a Callies or Lunati forged rotating assembly.

The engine currently has a Scat forged rotating assembly so I think it should be okay for the horsepower that it is currently making with an option to add NOS in the future.

Let me know if you have any additional questions.

gkull

First of all there is allot of misinformation on the internet, car rag magazines, and lack of knowledge by most engine builders. The second problem is cam manufactures know what is best from years of testing, but better judgment gives way to the bottom line of making money and giving the consumer what he wants. Like Thumper Cams and similar items that just sound like your motor is a race car, but really isn’t very functional or efficient. (For the all show parking lot cruisers)


On this forum we have a cam grinder who has favored less lift and duration on the exhaust because he believes that you are dealing with the high heat and pressure. So as soon as you lift the exhaust valve off the seat you have the majority flow. Also there might be some merit to earlier closing of the exhaust valve might creat less exhaust reversion by limiting overlap.

I have spent hundreds upon hundreds of hours on dyno simulation programs. They reward big valve lifts on both sides and higher additional exhaust duration.

I have some opinions on cam designs and heads formed by years of experience, but sadly I have never had the opportunity to spend enough dyno time just playing around with different cams and heads to actually accumulate scientific data.

Who is right?

C3 Stroker

I can understand your preference for a hydraulic cam if it suits your purpose...most go for a solid roller because it's easier to get more horsepower with it. Either way, a horsepower peak of around 6500 rpm is a good spec to shoot for with shift points near 7000 safe rpm.

Your hydraulic cam will spec at around 10° less duration than a comparable solid roller. I have a custom solid roller that works very well that specs at 250/254° duration @ .050 with 720/675 lift (1.6/1.5 rockers).....also a 4-7 swap. Heads are the key, I have AFR 210 Eliminators competition ported, 310 cfm. I could probably use larger heads (220's), but these flow well and allow great torque. I also had Dr J port my intake (World Motown) to flow about 350 cfm per cylinder.

This engine has similar characteristics as my former 383, 900 rpm idle, nice sound, easy driver on the street. Only one change....this engine has 628 hp and 585 tq. So go for it ... you'll like the 427.

63mako

http://www.cnc-motorsports.com/short...pistons-1.html
Shorter stroke will RPM with less piston speed. It will also clear cam, block and oil pan better with a sacrifice of 6 CI. Available with Compstar upgrade for $350. This gets you a new dart block, forged Callies rotating assembly, internally balanced and assembled 421 CI Short Block for $4100. I like these guys. I haven't used them but have a few friends that have and my machine shop guy buys his higher end rotating assemblies through them.
http://www.bbb.org/south-dakota/busi...s-sd-113002756

63mako

http://www.summitracing.com/parts/hr...make/chevrolet
Small base circle cam is likely needed. Here is one that will work well with the above SB and your intended use.

pauldana

No, I'm a woosss.... don't want to worry all the time about adjusting valves...

Thank you


Interesting though.. thx

thats just where i like to be...

that and a little more is what i am shooting for...

Thank you

Hey Kevin, thanks for popping in i called them and they are going to send 2 quoits, one short block finished, and another for just the rotating assembly and Dart SHP block... for there short block they are 4-6 weeks out, and i can have the parts in 7-10 days and do the work myself...dont want to miss the whole summer of racing events.... was scheduled to do Laguna seca and looks as if ill miss it and I am so bummed!
I ask for a Callies RA, and told him it needed to handle 800hp. He also reaffirmed that my 750 Demon was to small for this and I will need a 850... really loved my Demon.

pauldana

Brand:Howards Cams
Manufacturer's Part Number:113155-10S
Part Type:Camshafts
Product Line:Howards Cams Retrofit Hydraulic Roller Camshafts
Summit Racing Part Number:HRS-113155-10S

Cam Style:Hydraulic roller tappet
Basic Operating RPM Range:3,000-6,600
Intake Duration at 050 inch Lift:247
Exhaust Duration at 050 inch Lift:255
Duration at 050 inch Lift:247 int./255 exh.
Advertised Intake Duration:300
Advertised Exhaust Duration:308
Advertised Duration:300 int./308 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.600 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.600 in.
Valve Lift with Factory Rocker Arm Ratio:0.600 int./0.600 exh.
Lobe Separation (degrees):110
Camshaft Gear Attachment:3-bolt
Computer-Controlled Compatible:No
Valve Springs Required:Yes
Camshaft Manufacturers Description:Small base circle. Hot Street/bracket. Requires aftermarket heads, 3,500+ stall.
Quantity:Sold individually.
Notes:Small base circle cam. Retrofit roller cam for engines that did not originally come with a roller cam.
In-Store Pickup:Choose In-store pick-up (OH, GA, NV) on our web site.
Howards Cams retrofit hydraulic roller camshafts offer more lift and more power for less money. These street performance grinds are perfect for those wanting to upgrade to hydraulic roller cams. Manufactured using the highest grade race-quality cores, Howards precision-grinds their cams to provide the quality and performance that you want at a reasonable price. Overhaul your valvetrain for mild to wild street performance with Howards Cams retrofit hydraulic roller camshafts.

Crepitus

If your gonna use a stock panrail and cam tunnel position the 4' (427)stroke is a lot of custom hand fitting and experienced parts choice. The 3.85 stroke of the 421 helps out a lot. I completely understand how sweet the 427 Vette thing is . I think Crower is selling SBC rods with splayed rod bolts to help clear the cam. Imho I really dont like small base cams but it is probly a necessity here. I am really surprised the Honda journal or even smaller is not popular with the stroker combos. Assuming the bolt placement is moved toward the center of the journal this should help a lot with clearing the cam and rails. You would lose pin overlap and the related strength but on a street/strip engine I dont see that this would be a show stopper. The cost of the small journal stuff might be better spent on a raised cam wide rail block. As far as bang for the buck strokers I think 63Mako is right on target (as usual) with the comp star upgrade in the CNC short block. CNC has a exellant reputation with sportsman oval guys. Some of these CF forum guys really know their stuff about the SBC strokers this could become a very interesting thread. fwiw my background is mostly 355 and 406 short oval with a couple 600cid Fords for boats.

v2racing

You can take this with a grain of salt because it's second hand knowledge. A friend of mine was at a machine shop to buy a block and have it machined. He said the shop had several SHP and Little M blocks in stock. Dart claims the SHP is good to 4.165" bore and the Little M is good to 4.185" bore. My friend was curious and got the guy at the machine shop to sonic test the SHP's against the Little M's for cylinder wall thickness. He said there was virtually no difference between the wall thickness of the two different models of the Dart block. I have seen where some machine shops are boring SHP blocks to 4.185 with the 3.875 stroke to make a 427. I'm greedy and the 427 really is kind of a magic number for Corvettes. I would probably do it. Of course I would check wall thickness first. I have two different 406's now, so it's kind of hard to justify building a 427, especially to the wife!

As far as smaller exhaust lobes as compared to intakes, I have done a lot of work with this. If you have an exhaust port that flows very high percentages of the intake, the smaller exhaust lobe will make a better power band and better peak power. A big exhaust lobe with very high exhaust to intake flow will hurt power, especially in the bottom end. I can expand on this if anyone is interested.