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My New 68 400 Engline Build Does not seem quick?

3K views 9 replies 6 participants last post by  62 NovaWagon 
#1 ·
Hello everyone I was hoping you can help me with my Engine and Car setup?
Driving this car it does not feel as fast as it should I honestly cannot really tell the difference between my old 400 SBC with standard rods and stroke. I know a lot of people say that this should be a stump puller, but I think something is not quite right about the setup below. The car just does not seem to rev very fast in second gear it feels very long with the pedal down to the floor for it to go from 3k to 6500K. The car consistently chirps 2nd and sometimes 3rd but in first if I slam the gas its not peeling out on the stock tires.

Engine is a 427 (Motwon II Block 4” Stroke 6” Rods) All forged internals 10:2:1
Heads are Profilier 195 CNC ported by Chad Speier 72mm Chambers 2.05/1.6
Hydraulic Roller Cam:
Duration @ .50 Intake 237 Exhaust 240
Duration @ .004 Intake 296 Exhaust 299
Lobe lift .365 Intake .344 Exhaust
Valve lift @ 1.5 .547 Intake and .516 Exhaust (Car has 1.6 Rockers)
Lobe separation is 108
Overlap 22.5
Intake:
Victor JR
Carb:
Holly 650 CFM that has HP main body no choke horns, down dog legs, longer jets. (Carb person said it flows around 850CFM)
Transmission
200 4 R Art Carr non locking 2400 to 2800
Gears:
4.11
Car:
68 Nova
 
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#3 ·
I'd first be suspect of ignition timing like Art mentioned. Was the cam degreed during installation? I've have only had one that was off (big block) due to a mismarked dot or keyway location on the crank gear. I had to check it multiple times because I doubted my accuracy. Since then I never take it for granted that it'll be on or close! It would have run, albeit poorly and would have been a bear to diagnose:yes:. Double check your valve adjustment preload. Adequate fuel delivery would be a close second. Tire
diameter can make quite a difference as Art stated, particularly if you are right on the edge of duration requirements. I found that out on a 383 SBC with a 4.10 rear. Just switching from a 26" to a 28" tire turned the car into a dog! But that being said it was a smaller motor with quite a bit more cam.
Remember "Ignition first, fuel and then motor". That car should be a stump puller!:yes:
 
#5 ·
Nice engine combo! I have very similar cam specs in my 454, but I do run RPM Air Gap and useable rpm range is 1500-5500, 2.19/1.880 valves, running manual 5 speed with 3.73 final gear.

I am just following here to see how this progresses.

Did you ever dyno engine or on car on rolling dyno? to identify any potential dips or lack of useable torque.
 
#6 ·
Hello everyone I was hoping you can help me with my Engine and Car setup


Engine is a 427 (Motwon II Block 4” Stroke 6” Rods) All forged internals 10:2:1
Heads are Profilier 195 CNC ported by Chad Speier 72mm Chambers 2.05/1.6
Hydraulic Roller Cam:
Duration @ .50 Intake 237 Exhaust 240
Duration @ .004 Intake 296 Exhaust 299
Lobe lift .365 Intake .344 Exhaust
Valve lift @ 1.5 .547 Intake and .516 Exhaust (Car has 1.6 Rockers)
Lobe separation is 108
Overlap 22.5
Intake:
Victor JR
Carb:
Holly 650 CFM that has HP main body no choke horns, down dog legs, longer jets. (Carb person said it flows around 850CFM)
Transmission
200 4 R Art Carr non locking 2400 to 2800
Gears:
4.11
Car:
68 Nova

Why are you running a 650 CFM carb? WAY too small for a 427. Did you talk to Chad before you bought the heads for this set up? The heads are on the small side. Remember just because you have a small block, you are building a big block. As for taking so long to rev up in 2nd gear, you may want to look at your transmission.
 
#9 ·
Hey guys sorry for the delay. I took the car to a guy that races at Atco he agreed that it was a dog lol. 3 things wrong:
1. The floats set too high on carb flooding the engine
2. Timing was way low
3. The heater cables in the way of the back of the gas pedal causing no WOT.
After he set it up right i took it for a spin and had no problem breaking traction @ 50. Since I am not a carb person I decided to go with the complete Sniper setup. I just got the car back and could not be happier with everything. The car scares me now and that's what I was looking for. I will send over some dyno results soon I am looking to go at the end of December. Thank you for all of the responses, but the setup definitely was not the issue the combo to me is excellent.

I will post a few photos too!
 
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