world 454 sbc
10.56:1 comp
dart pro-1 230
dart single plane intake
mighty demon 850 annular discharge carb
msd digital e-curve distributor
hedman headers full 3" exhaust borla mufflers with x-pipe
holley 130+ gph mechanical fuel pump
comp cams hyd/roller 248/254 dur @ .57/.588 lift
tremec tko 600 5 speed with .64 over drive
4.10 rear gears
comp cams magnum full roller rockers 1.52:1 ratio

can anyone desktop dyno this info for me? or give any suggestions?
Thanks Steven

Can you provide bore x strokex rod length, cly head cc , piston volume? etc. Otherwise I would say 600 hp @ 6500 x 560 tq @ 5000
HP responds to a larger cam , 312x 306 advertised duration. Also responds to more compression.

bore-4.250
stroke- 4
6" h-beam rods
72cc chamber
-12cc piston volume

Here ya go
Not your cam probly. gimme a comp cams part #

Check for errors, lemme know

oh yeah, I put you .010 in the hole w/ a .037 head gasket. you didn't say.

I did that to lower your compression from 11 to 10.77, you said 10.56

Which is making me think I don't remember what head cc I used. I'll check real quick

---------------- -------------------
yeah I put 72cc heads 12 cc vr .010 +.037

my cam is a custom grind
here is the card info

dur @.oo6 tappet lift: int299/exh305
valve timing @ .050: open close
in 18 BTDC 50 ABDC
ex 61 BBDC 13 ATDC

Cam installed @ 106.0 intake center line

dur @ .050 in248 ex 254
lobe lift with 1.52 rockers
in .57 ex .588
lobe sep 110.0

Thanks again!!!
Steven

my gaskets have a compressed thickness of .051
im not sure on how far they sit in the cylinder

You don't want those gaskets then. Get thinner ones.
You want your quench to be 40ish(gkt + deck) theory says it helps w/ detonation.

Ok, I deleted the pdf file in the #4 post and resaved with your cam specs . And here it is again. But didn't help much.

The low lift is hurting you. But that depends on your objective. I think this would make a very strong and dependable, long lived engine. If you are wanting a strong daily driver. 3300# car probly get you in 11's

Well the stuff I plugged in was about what you got, rod , cam and I had flow # for those heads. You are running a 12-444-8 cam XR300Hr the way I figure it. I just plugged in your final compression and run large tube open headers. There are prolly better cams out there , this being a hyd roller but unless you are all out , what you got will work. You have some decent flowing heads.
What Tim showed you is the same as what I find as he has same program I do.

i think this is the only sbc gasket with a 4.25 bore. it is the same one used by world themselves

I was wrong about lift hurting. I cranked it up to .650 for negligible benefit. I also advanced it up to 10° and retarded it up to 8 or 10° (all in 2° increments) and couldn't see a real payout. I liked it best set at the 106° they call for.

I hope you have a zero deck. Not that big of a difference though. I guess just hope you are not very far in the hole:)

What's the car gonna do for a living?

the cam is grinded at a 4 degrees advance the motown block has a 9.025 deck hieght it will be a street car sometimes driven heavily:yes:

+- .025 deck + .051 gasket will be about .075 quench. I dont like this even if you give or take a little. Not doing much for detonation and is sure dropping compression. A smaller cam with less overlap may help compression cly sweep. That block should have been cut below piston deck using that thick of a head gasket. I guess you rod / piston combo resulted in a stock compression height? But , like Tim asked, what will this motor be doing, Sonic or strip? As for cam , all Comps have 4* built in, did you install another 4?

+- .025 deck + .051 gasket will be about .075 quench. I dont like this even if you give or take a little. Not doing much for detonation and is sure dropping compression. A smaller cam with less overlap may help compression cly sweep. That block should have been cut below piston deck using that thick of a head gasket. I guess you rod / piston combo resulted in a stock compression height? But , like Tim asked, what will this motor be doing, Sonic or strip? As for cam , all Comps have 4* built in, did you install another 4?


The sim I gave him is at Zero, so comp cam and comp dynosim it will be same same huh?

I also did quick iterations on it, but it made no diff mebbe even hurt it in my opinion. I don't really like the iterations except to play. Iterations will move the lobe orientations so to me it's irrelevant with cam in hand. Don't worry stamatisg, none of that crap got near the sim you have.

Yeah Don, I'm with you not liking the quench. I haven't ever done any testing of my own on the quench vs detonation theory but I always figger
1. If it's a theory I can accept the logic of

and

2. People who get good results apply it

then

3. It's easy to do and a guy really ought to pay attention to it. I would ask around for sure, call Motown call gasket people etc. Maybe a small block 454 is a different critter, but if you run into vendors that treat you like you are asking questions nobody else asks it just might mean they don't know too much. There's got to be a thin gasket in that bore. People have been using gaskets to change CR forever.



That said, I've built a bunch of Chevy's without ever giving it a seconds thought. But that was long ago and most of em were on LP. These days I look at it unless I just want to make it run(like I did on my 283, I hadn't heard it run in 10 yrs and just needed to hear it again so slapped it together w/ a set of flat tops and 68 cc heads poor little guy I'm amazed it even ignited:D. I didn't like it and let it sit around a few. Now I got pistons:D:D:D so it is a toy again)

This is the closest I can get to 4.250 , may be others but look at the price. .032

http://www.sdparts.com/product/SCET11203/SBChevy4200X032SCETitanCopperHeadGasket.aspx

thanks for all the replies!! i talked to my engine builder (Ohio Crankshaft) and they said that with the gaskets i have along with the -12cc pistons and a 72cc combustion chamber i will be running 10.57:1 cr. they also said the piston at TDC is flush with the deck. and the cam was not installed an additional 4 degrees.
comp cams tech guy gave me the best grind for my combo. it is a small base circle cam
part# 12-000-9
grind: 3318/3319 HR 110 + 4 advance
thanks again

Steven

Sounds better. So basically your gasket thickness is your quench. The 9 in your cam number indicates its a steel billet, brass or poly dist gear required unless its go the optional iron gear installed.

i have the comp cams dyno software and virtual engine pro. the comp cams software give me better #'s and the other na little lower. I wanted to see if any one has a more accurate software out there. by the way what kind of idle will i have with this cam?
thanks

Steven

i did my own measurement and put the #1 piston at TDC towards the lifter valley side it is flush with the block, towards the side of the block it is sunk about .005. i guess this is normal.

Thats good, its been cut. Some of that is piston rock. This cam is a tad above mine, It idles well at 950 rpm, drops to 8 when I turn AC on.

You have to average the deck clearance. The piston will not be square in the bore when at rest.

I use a depth mike. Or dial calipers for quick-fast. Straight edge and feeler gauge would work. Finger and eyeball for real quick-fast.

thanks again guys you have been very helpful
just one more question. i have a set of dart pro-1's should i get the intake that has the 9.025 deck hieght or the standard?
thanks again
Steven

thanks again guys you have been very helpful
just one more question. i have a set of dart pro-1's should i get the intake that has the 9.025 deck hieght or the standard?
thanks again
Steven


I'm not familiar with that. I know you are supposed to mill the intake or the intake surface of the heads if you mill the head surface on a 1.2:1 ratio.

Looking at the dart catalog appears to me you are confusing the tall deck and standard deck AND the dominator 4500 manifold

42411000 appears to me what you want. What part # did you have?

http://www.dartheads.com/manager/uploads/catalog%2004.pdf