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Lets see what you guys did with vortec heads, include cam shaft, rocker arms, type of springs (stock, beehive, etc), just everything pretty much...
HP and torque ratings! Quarter mile times!
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.010 over L31 long block
xr 282 hr comp roller cam
10.24:1 comp.
6.0 rods
mild porting on the heads
comp springs
Stock rockers were slotted for the higher lift cam (no dyno info since rollers were added)
summit intake (port matched)
750 cfm holley 3310
stock bbc oil pump
holley blue fuel pump
accel billet dizzy
426hp 432 lbs at the flywheel
Once I get the bugs worked out, I should get low 12's or high 11's. Right now it's 12.84 @ 109.3
Vortec heads w/ three angle vavle job, elongated push rod holes and screw in studs w/ guide plates,
Comp Pro Magnum 1.6 rockers,
Comp Pro Magnum push rods,
1979 350 4-bolt "010" block, std. bore,
Speed Pro Hypereutectic coated pistons w. moly ring pack,
Stock rods resized w/ ARP bolts,
Stock cast crank, polished,
Fluidampr balancer,
SFI flexplate,
Clevite bearings,
Stock oil pump w/ Z-28 spring,
Victor Reinz .026" head gasket,
Rpm Air Gap intake,
Holley 670 Street Avenger,
Comp XR276HR cam,
Mallory distributor w/ 18* total mechanical advance ( 16* initial )
MSD 6AL ignition,
Flamethrower coil,
Hedman LT headers, 1 5/8" w/ 2 1/2" by xxx collectors,
Still dialing in the combination with 700R4, TCI Street Fighter convertor, 3.70 gear and 26" drag radials. Best so far of 12.9 @ 107 w/ 1.79 60' ( Broke pinion gear on that one )
Race weight 3650lbs w/ driver and a full tank of 94 Octane,
22 mpg on the highway.
I guess I have a little more to do..... Skinny has more weight and less cam and carb then me, and the same times. He does have slicks though, so that may make up for it. I'm at 3340 with driver and 94 octane. I think his carb and cam are much more street friendly, and responsive. I have a lt1 cam out of a police cruiser i have been thinking of grinding the end on and installing. It would put me somewhere between 330 and 350 hp though, and my carb is already to much.... real overkill then.
A friends setup for you..... I don't know the power though
383 stroker
880 block
6.0 rods
9.6:1 comp
xr252hr cam
Qjet.... stock tune still. he's only adjusted the idle.
gmpp intake with a spacer
four speed with creeper
14 bolt posi, with 3.08 gears
I'm not sure if the engine caused it, but he cracked the ring gear in the rear end the day after we put in the engine. This engine is in a 1-ton truck and will tow almost as good as a desiel.
I guess I have a little more to do..... Skinny has more weight and less cam and carb then me, and the same times. He does have slicks though, so that may make up for it. I'm at 3340 with driver and 94 octane. I think his carb and cam are much more street friendly, and responsive. I have a lt1 cam out of a police cruiser i have been thinking of grinding the end on and installing. It would put me somewhere between 330 and 350 hp though, and my carb is already to much.... real overkill then.
Is that LT1 cam out of a B4C Camaro or 9C1 Caprice?
If its out of the Caprice it will be 192/197 .412/.427" on a 112ºLSA(L994.3V8, Vortec 305/350cam)
B4C will be 210/208º.447"/.459"(depending on year)
Small indeed. Or is that what you want to do, downsize?
I guess I have a little more to do..... Skinny has more weight and less cam and carb then me, and the same times. He does have slicks though, so that may make up for it. I'm at 3340 with driver and 94 octane. I think his carb and cam are much more street friendly, and responsive. I have a lt1 cam out of a police cruiser i have been thinking of grinding the end on and installing. It would put me somewhere between 330 and 350 hp though, and my carb is already to much.... real overkill then.
How did you come up with your 10.24:1 CR?
Head gasket?
Are you zero decked?
I don't have the stock style dished pistons in there. If I remember right the guy that did my machining said it was 0.025 deck, and a 0.032 head gasket. It was an older guy that has been doing this for 40 years.... I told him my goals, and he gave me part numbers to order. I used an online calculator to figure it out. The pistons I used were supposed to be 10.63:1, but it didn't come out to it. I don't know how the manufacturers figure out their numbers.
As for the cam, it's a 9C1. I don't want to downsize that far, but I think a step or so smaller would be a little better. My car is a little worse on low end then I'd like for a daily driver. I thought i could get away with going with a bigger cam then I should, since I was useing a roller. It's still a daily driver with that cam though.
The oil pump had given out, and it burned up a couple bearings. It had 40k miles and the cylinders still looked good. The entire rotating assembly got replaced. Could you imagine using them pistons in a performane engine? That can't be over 9:1 at best. I tried loading a pic of it when I had it apart the first time, but It's not working for me right now.
Last edited by doc221978; 11-17-2008 at 04:11 AM.
Reason: Tried to attach a file
It's difficult to get an accurate number for your static and dynamic compression ratio without knowing the piston type. If I use the 282 cam (installed on a 106 CL) with your piston deck, head gasket, rods etc and use my pistons ( flat tops with 5cc valve reliefs ) I manage a 9.88:1 static compression ratio. That would be fine if your cam didn't produce a dynamic compression ratio of 7.75:1. Although a little on the low side that's assuming you don't have more piston relief and that the cam has been installed and degreed correctly.
Finding out what pistons you have will help to determine if your comp ratio is just too low for building low engine speed torque.
Last edited by skinny z; 11-18-2008 at 11:58 PM.
Reason: terrible spelling
It's been a while, and I can't find the online calculator I used. The pistons are a .150 dome. I know that raises the compression, but I also know that not everything I find on the net is right.
I don't get the differance between static, and dynamic. Are you talking about how the higher duration bleeds off pressure?
I appreciate the info.... I have built a couple engines after all the machining was done, but I have always used combinations that I have seen others use with success.
I just read for a while on dynamic compression. It took a little while to understand. I figure I have about 8.91 DCR. It seems as if 7.5-8.5 is the best. My math has to be off though. I am thinking a high lift and shorter duration.
I'm going with a 350 .030 over, Keith Black KB-193 -12cc D dish pistons, eagle rods, new Scoggins/Dickey vortec heads, comp pro magnum rockers, Edelbrock vortec TPI base, 22lb injectors, L98 cam, to go along with my hooker headers and cat back. The motor will be backed by a T56 and 3.73 rear. I'm hoping for around 275-300 hp at the wheels.
I just read for a while on dynamic compression. It took a little while to understand. I figure I have about 8.91 DCR. It seems as if 7.5-8.5 is the best. My math has to be off though. I am thinking a high lift and shorter duration.
This is the article I refer to and there is a link to the calculator I use in it.
If you had the dome volume ( not height ) then you could get an accurate idea of how much static compression you have. From there you either: Change the SCR to suit the cam or change the cam to suit the SCR. Ultimately, you are trying to achieve the highest dynamic ratio to meet your vehicle requirements.
I remember reading an article in Chevy Hi Performance or Super Chevy, one of those, with a 383, same cam, same heads (bone stock), Edelbrock intake and 750 carb and IIRC it put down like 420hp and 450 ft/lbs at the flywheel, Ima see if I can find that thing laying around here. In my opinion, if you're going Vortec and dont wanna use a roller cam, XE274 is pretty stout and will yield damn good numbers. I can't wait to see what the HSR and MegaSquirt bring me
Ya, me and him have talked a little. He's running a different cam than I am, and I can't remember if he's running Vortecs or not.
That carcraft looks like it might be it, either that or they did a build up similar to CHP. I coulda sworn I read it in CHP, that's the only mag I have a subscription to.
Its a full interior Z28. Manual windows, etc. T-tops. Only thing missing in the car is the spare tire and floor mats.
1.69 60'
If I remember right it was on a set of worn out Sportsman Pros'. Now I will say my co-worker ran this time and my best was a 12.7x but the setup ran it. After busting 2 sets of gears in a month I went easy on the car and Its been sitting for a few years.
[quote=spills;3951486]Ya, me and him have talked a little. He's running a different cam than I am, and I can't remember if he's running Vortecs or not.
QUOTE]
AFR 195's. Maybe the best small block heads going.
Which differential? I've busted a pinion myself and am considering an upgrade.
1.69 60' isn't too shabby. What's your launch rpm?
Good old 10 bolt with way too much money in it . Eaton Posi, 28 spline axles, rear axle cover and brace kit. I would either hold the rpms about 3000-4000 and then stab it.
Took the same engine and changed the cam to a Erson E110030K
specs>> 284/284 218/218 .458/.458 114. Killed the power made 375 HP and 420TQ. Engine runs alot smoother and works well in my IROC with 700R4.
__________________ It is the fastest car in town as long as it stays in the garage.
Interesting. Those are the same cam specs ( w/ 110 LSA) as the Clevite cam I was using prior to the roller I use now. That little cam managed a 13.2 @ 106 mph in a 3700 lb car.
The .450" lift rule cam must have had a ton of duration to make those power numbers. Impressive.
4 bolt main block
bored .030
Scoggin-Dickey large tube TPI vortec intake
Large tube runners
ported Plenum
GM Fastburn Heads
52mm BBK throttle body
1.6 GM full roller rockers
26 lb. ford injectors
LT4 Hot Cam
Hooker Shorties
5 speed
Aluminum Driveshaft
3.73 Posi
Next Step is to Stroke It
406 ci
+.030 2 bolt 400sbc 0 decked
cast GM 400 crank
GM 062 Vortec heads: ported with 2.02x 1.60 manley valves
KB 168+.030 pistons
GM 5.7 rods
9.8:1 cr
CrossWind dual plane intake Holley/Proform custom build 750 HP carb
Carter P4594 electric fuel pump GM "L-88" air cleaner
Comp XE284H-10 hyd ft cam w/Crane roller tip 1.5 rockers
GM HEI w/MSD coil (locked mech adv)
1-5/8" long tube headers 2.5" custom built dual exhaust
Custom self built dual "turbo" mufflers.
TH-350 w/B&M holeshot 3600 converter
4.10's w/Auburn posi +Air-Lift Drag Bags
M/T ET Street/Sportsman Pro tires
11.92@115 1.60 60ft
Get a REAL Converter in it, and it'll probably pick up a 3-4 tenths and some MPH....Good possibly go some 11.50's, maybe some high .40's at 116-117....
...What are your 1/8 mile ET's and MPH?
Thats one reason I changed the cam, the duration was so high that the ramp rate was very agressive and may not last long on the street.
Besides wiping out that flat tappet Clevite cam I has been using, I'd always wanted to go to a roller profile. I could get those fast acting lobes and benefit from the better than average flow rates of the Vortecs at about .5'' lift.
With the 1.6 rockers I'm in the .530"/.540" range and can still keep duration around 224/230*. Excellent street manners, nice lope at idle and great gas mileage.
I just want to go faster. I think 12.5's are in this setup.
That's why I'm checking other Vortec combinations.
. Eaton Posi, 28 spline axles, rear axle cover and brace kit. I would either hold the rpms about 3000-4000 and then stab it. 
