Yellow Bullet Forums banner
1 - 20 of 26 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
This is my first post with Yellowbullet. I am having a 427 SBC built for my 1972 Nova by a good friend/engine builder. 2nd opinions are what I am asking for. This is a real street car and not much a street/strip car. I want it to be quick but not radical, except for a good idle sound. I am listing everything that I currently have below and then listing what I still have to purchase, engine wise. Please let me know if I am making a mistake on anything. Thanks in advance

Already purchased

Dart Little M block, standard deck height and cam location
PBM/Scat 4.00" Crankshaft
PBM/Scat 6.00" rods that have been clearanced for camshaft
Hamburger oil pan and matching pump/pick-up
PBM flat top top pistons and rings Erson-PBM-World-B2C | PF4125000 - PBM Performance - Forged Power Piston - SBC - Flat Top - 4.125" Bore - .927 pin - 6.000 Rod - 4.000 Stroke - 1.000 CH - 415 g
AFR 220 Competition CNC 76cc chamber heads (I've read these may be too small but this is for a real street car)
Competition Cams Stainless rocker arms 1.7 intake/1.6 exhaust
Edelbrock Super Victor intake (Will be converting to port fuel injection)
Wilson throttle body and injecctor rails
MSD Distributor# 85555
BAM .842 lifters
Injectors too but I can't remeber then name or volume (They have enough flow to accomodate a 200hp shot of nitrous)
Jake's Performance 4L80E and 3000 single disc lockup converter


Things needed to complete the build

Hydraulic roller camshaft (I'd like to hear recommendations to compare. I do not have power brakes so vacuum is not an issue)
ECU to run things
Still have to decide on a 3.55 gear or 3.73 gear with my 27" tires

Once again, thanks!!!!
 

·
Registered
Joined
·
2,050 Posts
Heads are fine and will make plenty of power on a 427 and with the right cam power peak will still be above 6000RPM. I have them on my little M 400 sbc, but I have a procharger so it is hard to compare.

How many miles do you plan to drive it a year. Honestly for me, any type of hotrod/weekend car I would go with a solid roller cam for a sbc... I just like the fact that lifter goes up, valves open... easy peasy lol. Selecting a cam is going to be very important no matter solid or hydraulic so make sure and go to someone reputable and be VERY honest in how you want the car to behave and what type of power band you are looking for. Might need to get another 8 rockers depending on the cam choice.

If you have OD transmission I would definitely go with 3.73s

NA, 10.5:1 compression, those comp port heads, and no worry about vacuum... it should make over 525hp like falling out of a tree. Right cam and tuning, 575hp-600hp is do-able.

As far as a 200hp shot of nitrous, I am absolutely no expert in that at all, but I would ask some people that know better if they would trust that brand/alloy piston with a 200 shot with a rod and stroke that long.
 

·
Registered
Joined
·
20,577 Posts
Roughed into PipeMax for fun.


427.650 Cubic Inches @ 6500 RPM with xxx.00 % Volumetric Efficiency PerCent

Required Intake Flow between 257.7 CFM and 272.4 CFM at 28 Inches
Required Exhaust Flow between 176.6 CFM and 199.2 CFM at 28 Inches

600 RPM/Sec Dyno Test Lowest Low Average Best
Peak HorsePower 530.8 552.6 563.5 574.5
Peak Torque Lbs-Ft 475.5 495.0 504.8 514.6

HorsePower per CID 1.241 1.292 1.318 1.343
Torque per Cubic Inch 1.112 1.158 1.180 1.203

BMEP in psi 167.7 174.6 178.0 181.5
Carb CFM at 1.5 in Hg. 804 895 940 985

Target EGT= 1360 degrees F at end of 4 second 600 RPM/Sec Dyno accel. test
Octane (R+M)/2 Method = 94.1 to 96.5 Octane required range
Air Standard Efficiency = 61.50563 % for 10.500:1 Compression Ratio

Peak HorsePower calculated from Cylinder Head Flow CFM only
600 RPM/Sec Dyno Test Lowest Average Best Potential
Head Flow Peak HP = 490.7 575.2 659.7
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #4 ·
Heads are fine and will make plenty of power on a 427 and with the right cam power peak will still be above 6000RPM. I have them on my little M 400 sbc, but I have a procharger so it is hard to compare.

How many miles do you plan to drive it a year. Honestly for me, any type of hotrod/weekend car I would go with a solid roller cam for a sbc... I just like the fact that lifter goes up, valves open... easy peasy lol. Selecting a cam is going to be very important no matter solid or hydraulic so make sure and go to someone reputable and be VERY honest in how you want the car to behave and what type of power band you are looking for. Might need to get another 8 rockers depending on the cam choice.

If you have OD transmission I would definitely go with 3.73s

NA, 10.5:1 compression, those comp port heads, and no worry about vacuum... it should make over 525hp like falling out of a tree. Right cam and tuning, 575hp-600hp is do-able.

As far as a 200hp shot of nitrous, I am absolutely no expert in that at all, but I would ask some people that know better if they would trust that brand/alloy piston with a 200 shot with a rod and stroke that long.
Heads are fine and will make plenty of power on a 427 and with the right cam power peak will still be above 6000RPM. I have them on my little M 400 sbc, but I have a procharger so it is hard to compare.

How many miles do you plan to drive it a year. Honestly for me, any type of hotrod/weekend car I would go with a solid roller cam for a sbc... I just like the fact that lifter goes up, valves open... easy peasy lol. Selecting a cam is going to be very important no matter solid or hydraulic so make sure and go to someone reputable and be VERY honest in how you want the car to behave and what type of power band you are looking for. Might need to get another 8 rockers depending on the cam choice.

If you have OD transmission I would definitely go with 3.73s

NA, 10.5:1 compression, those comp port heads, and no worry about vacuum... it should make over 525hp like falling out of a tree. Right cam and tuning, 575hp-600hp is do-able.

As far as a 200hp shot of nitrous, I am absolutely no expert in that at all, but I would ask some people that know better if they would trust that brand/alloy piston with a 200 shot with a rod and stroke that long.
Thank you for your replying. It "might" get driven 3000 miles a year, but probably less. I understand what you mean about the camshaft, and being honest with myself. Unfortunately, I can't understand cam specs with this size motor. My engine builder is suggesting something in the 250 @ .050 range. That seems really big to me but he said a 427 will tame it tremendously.
 

·
Registered
Joined
·
58,962 Posts
We reconvened with Jack McInnis, Tony McAfee, and Jeff Lake at Dart to finish the build and dyno test the small-block to see if we had a winner, or wishful thinking. Last month, the crew at Dart machined and assembled a stout SHP short-block as the foundation for our anti-LS engine. Using the company's iron SHP block with a 4.000-inch bore, they tossed in a 3.750-inch Eagle crank, CompStar steel H-beam rods, Mahle flat-top pistons and a COMP Cams solid-roller camshaft.

Not even close to 427 cu in.....
 

·
Registered
'73 Camaro NETO/N
Joined
·
576 Posts
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #8 ·
Definitely a bit more on the "race" side than mine will be. My cam will be 10-15 degrees shorter probably. Less compression too. I'd be happy with 50-60 horsepower less and more driveability. Hopefully the fuel injection helps me with that.
 

·
Registered
Joined
·
2,050 Posts
Thank you for your replying. It "might" get driven 3000 miles a year, but probably less. I understand what you mean about the camshaft, and being honest with myself. Unfortunately, I can't understand cam specs with this size motor. My engine builder is suggesting something in the 250 @ .050 range. That seems really big to me but he said a 427 will tame it tremendously.
My motor is a 400ci with same heads and intake you have. My cam is 255/[email protected] and lift with 1.6 rockers is right around 0.680" and it is on a 113. I have had this combo both carbed and efi... cam is definitely not too big. I have no power brakes either so that isnt a problem. It makes about 8" of vacuum I think.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #10 ·
My motor is a 400ci with same heads and intake you have. My cam is 255/[email protected] and lift with 1.6 rockers is right around 0.680" and it is on a 113. I have had this combo both carbed and efi... cam is definitely not too big. I have no power brakes either so that isnt a problem. It makes about 8" of vacuum I think.
Wingnutks, this is exactly the info I was looking for. Since I am doing a retro-port fuel injection, I assume it will help driveability and the idle too. How did you like fuel injection on yours?
 

·
Registered
Joined
·
2,050 Posts
Wingnutks, this is exactly the info I was looking for. Since I am doing a retro-port fuel injection, I assume it will help driveability and the idle too. How did you like fuel injection on yours?
I was blow thru on e85. Biggest difference for me was I needed more mid throttle drivability. Motor makes a touch over 900hp, so on the street having 1/3-2/3 throttle was a big deal. With the carb if you stayed at half throttle too long the power valves would just dump fuel and it would be blubbery rich. Normal driving and wot, it was perfect. The EFI made it alot nicer to play around with on the street...idle, cruise, wot... not much different. Car ran 9.4 @141 both EFI and Carb. I am sure with more time I could have gotten the carb much better at 1/2 throttle by staggering power valves and stuff.
Knowing what I know now for a boosted motor I would definitely spring for EFI. For a NA motor if cost wasent an issue, Id go EFI as well. Considering costs... not sure. My old motor was a 10.8:1 400 sbc, 244/252 solid flat tappet. I drove it everywhere, it ran [email protected] at 3450lbs. It was carbed and drivability was fine in everyway.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #15 ·
SBC 421 with AFR 220 and my semi custom hyd roller for AFR headed SBC with EFI. This engine had the FAST system on it. .612/580 238/242 on a 109.
This is RWHP in a C3 Corvette....

View attachment 425909
Chris, I would be happy if mine did the same thing. I want to talk about a camshaft when the build is close to being finished. Also, do you like Holley for the ECU? I still have to purchase that.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #16 ·
I was blow thru on e85. Biggest difference for me was I needed more mid throttle drivability. Motor makes a touch over 900hp, so on the street having 1/3-2/3 throttle was a big deal. With the carb if you stayed at half throttle too long the power valves would just dump fuel and it would be blubbery rich. Normal driving and wot, it was perfect. The EFI made it alot nicer to play around with on the street...idle, cruise, wot... not much different. Car ran 9.4 @141 both EFI and Carb. I am sure with more time I could have gotten the carb much better at 1/2 throttle by staggering power valves and stuff.
Knowing what I know now for a boosted motor I would definitely spring for EFI. For a NA motor if cost wasent an issue, Id go EFI as well. Considering costs... not sure. My old motor was a 10.8:1 400 sbc, 244/252 solid flat tappet. I drove it everywhere, it ran [email protected] at 3450lbs. It was carbed and drivability was fine in everyway.
What type of EFI did you use? I still have to purchase an ECU
 

·
Registered
'73 Camaro NETO/N
Joined
·
576 Posts
SBC 421 with AFR 220 and my semi custom hyd roller for AFR headed SBC with EFI. This engine had the FAST system on it. .612/580 238/242 on a 109.
I'm in the planning process of a fresh build. I was originally thinking a high compression 406 with the AFR 220 (65cc) comp heads and Eliminator intake, but I'm leaning towards a flat-top piston 421.
 

·
Registered
Joined
·
4,260 Posts
Chris, I would be happy if mine did the same thing. I want to talk about a camshaft when the build is close to being finished. Also, do you like Holley for the ECU? I still have to purchase that.
The Holley stuff works very well. That's what I would recommend. Just give me a shout when your ready.
 
1 - 20 of 26 Posts
Top