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Discussion Starter #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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What is your initial timing, all in timing and what rpm does it hit the all in.
 

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I’d check timing like the OP said. That thing should have some crazy torque and be responsive with the fairly small heads. They should have great port velocity.
 

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Discussion Starter #4 (Edited)
I have the timing at idle set around 22 Degrees which i know is high but i am not getting any kind of denotation. I think the silver and blue springs in right now. Stock Bushing.
 

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That does seem off. I would have thought you would have trouble not smoking the tires in Second gear, especially with 4:11 gears. Any dyno time? What do you have for exhaust?


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Discussion Starter #6
No dyno yet. ceramic coated flowtech headers i think they step up to 1 7/8" with a 3" collector. then i go 2.5" x pipe then pypes racepro up over the axel and dump near quarter panel.
 

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I’m not an expert engine tuner, just throwing out ideas and thoughts. Initial timing seems high, based on what I’ve read. Does it have vacuum and/or mechanical advance? Do you know what your total advance is? Carb seems small to me too, but you’ve said it’s modified. Have access to a bigger carb to try? Plugs look good? Does the car smell rich at all? Any smoke in wot? Engine run hot or cold? You’ve checked wot? Pedal to the floor = butterflies wide open? Forgive the seemingly stupid questions, just trying to establish a baseline. Your combination should be pretty nasty I think. Light car, gears, HP big block, headers, exhaust.

That cam duration sounds long too. Based on dyno videos I’ve watched, the longer duration cams seem to make more peak HP but less low end grunt. Admittedly, I know next to nothing about cams.

Lastly, torque converters and cams have to work together right? You may need a high stall converter to keep that monster in its power band?

I’ll shut up now. Many more experienced experts out there. Usually all I have to do is say something stupid to encourage them to speak up. Good luck.


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Here's my thoughts,
That's alot of overlap with that low of compression. Are you 100% that the compression is really 10.2-1????
Combined that with a single plane intake and hardly any sizable stall makes for poor low speed torque.
I'd run a ported RPM intake if your only looking for 6500 rpms and street driving.
Do you have any flow numbers on the heads?
I'd run a smaller cam with bigger port volume heads on a 427 cubed motor.
Also why the non lockup???
 

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Discussion Starter #10
No Vac Advance.. The compression is 10:2:1. I am really only looking for a well mannered street car. Back when I got the 200r4 Art carr said that this is the best torque converter for this engine but who knows. The heads have to flow well at least I know its more than the 195 because of the porting done also intake ports are a very nice size. I am suspecting either the carb not actually being big enough, the intake is hurting it, or the torque converter sucks and is incorrect.

I do have an RPM airgap intake but the victor was port matched also crazy how small the ports are on the airgap.

You guys think the 2 plane airgap would make an improvement?
 

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I would double check timing. That thing should have crazy torque. I run a 421. Super vic jr, 220 AFR’s, huge Straub solid roller, 11.1 compression, 875 king demon, 4.10 gears and a fairly tight converter. Engine is super responsive. Just ran it last weekend at the track. Was cutting 1.50 sixtys leaving at idle. So with all that said...your car should be very similar. Something isn’t right. I would check that timing again. Put as much in before it starts hard or doesn’t want to shut off. Or has detonation.
 

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Was the cam degree'd in at install??

Nothing else on your list points to anything obvious...carb too small just chops off top end power, but will be a chainsaw fast response at lower rpms unless something is wrong elsewhere...same with the intake manifold, a Vic Jr on 427" will have more low end torque and throttle respnse than you know what to do with on anything short of 14" wide slicks.

That thing should blaze the tire from a 20 mph roll in second gear on any kind of regular street radial, even 325mm wide tire....should even blaze a Drag Radial on unprepped pavement. That isn't that big of a cam in a 427 " engine, it's not too big at all.

Trust Art Carr on the non-lock-up...there is a reason he was the pioneer on the use of the 200-4R that was stock in the Turbo Buick Grand /national in the 1980's, his stuff was fast and strong, guys were running in the high 8's at 145+ mph 1/4 mile with that trrans and converter from him.....he's forgotten more about the 200-4R than most have ever even learned.

To me it sounds like a cam insrtalled with the wrong keyway on a multi keyway timing set lined up with the wrong dot on the gear. Sounds like cam is badly retarded.

If everything was installed right, with that list of parts combined with the 2.74 low gear in the 200-4R and 4.11 rear gears that thing should light them up at will, and blaze them as long as you want to hold the pedal down.

It's not the carb, it's not the intake, and I'm 98% sure it isn't the converter...my money is something fundamental in the assembly process got missed. Cam degreeing, TDC mark/balancer verification, lifters set too tight, ignition timing off because TDC mark is incorrect, something along those lines.

With a timing light it is impossible to "be a tooth off" on the distributor....you just crank the distributor body around farther to get it timed to the crank again....the only time "a tooth off" comes into play is when you can't turn the distributor body enough , like the vac can hits the intake casting or firewall or the plug wires won't flex that far and it limits you from turning the distributor body far enough to get it into time.
A lot of guys just can't seem to grasp this fact.
 

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Discussion Starter #15
The intake is a super victor not victor jr my mistake!

The cam was installed by the engine builder so I would assume that is correct. I did install the balancer myself and also verified that piston was up top of cylinder one. Now that does not mean that it's not a few degrees off the zero mark. I will go ahead and check timing again and see if i can get my pointer to direct top dead center.

I appreciate everyone's response and glad to hear from you that this should be peeling the tires off like i thought.
 

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There is a thread over on the Team Chevelle forum where a guy found out his local "performance engine builder/machinist" installed his cam 7 degrees' retarded "because he"didn't believe the cam card was right" and the valvespring at a .100" too tall seat height giving something like a 90 lbs seat prssure for a fairly aggressive hydraulic rooler cam that should have had 120+ lbs seat pressure....he has spent the last 3 or so years trying to figure out why it was slower than expected, didn't rpm well, and had broken 5 or 6 of the original set of valvesprings. He finally decided to go online to a forum and start asking the questions needed to learn how to figure out whatwas wrong and not go back to the guy who messed it up in the first place and had been replacing broken parts for him.

I'd verify Piston TDC and balancer line/tab match, then stick a degree wheel and dial indicator on it and just do a quick intake lobe open and closing point determination to make sure the cam is in time with the crank the way it should be..

If you don't have a degree wheel,you can download a printable copy here and glue it to anything round, flat, and solid enough to allow a bolt hole through the center to survive the process...a cheap small cookie sheet or pie tin, plastic picnic plate, cheap Wally World plastic dinner plate, kids plastic frisbee, 12" hard vinyl floor tile cut into a circle, use you imagination.


If you don't have a dial indicator and magnetic base, you should get one, every serious hotrodder should have one and you can get a base and indicator from Ebay, Amazon, or Harbor Freigth for less than $40
 

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I think Ericnova has brought up some valid points.... and I agree that something does not seem right with the OP's engine. I have a 400 sbc with a similar build as the OP (10.1, similar hydraulic roller specs, 195 AFR heads, 2004R, 2800 stall, 4.10 posi rear... but I am using an RPM Air Gap) and I have no problem lighting up my rear tires (255 drag radials) while in 1st gear.

I was also thinking about the crank gear may not be "in sync" with the cam gear.
One other item to consider in your search for "lack of low end torque"... OP mentioned that a roller cam was installed in the engine. I'm not 100% sure, but I did not see any provisions for a factory type roller cam retainer plate on the Motown II block and a cam button would need to be installed to eliminate "cam walk". Do you know if that was done?
 

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Pull a plug out and post a pic. Also, as as stated previously, check your timing at say 4000 rpm. You should have at least 35 deg of timing in there. I second taking some time to verify Ericnova's suggestions. I just finished my car and didn't think to check to see if was getting full throttle. I checked it this weekend and I was getting maybe 1/2 throttle! What a difference that made.
 

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Was the cam degree'd in at install??

Nothing else on your list points to anything obvious...carb too small just chops off top end power, but will be a chainsaw fast response at lower rpms unless something is wrong elsewhere...same with the intake manifold, a Vic Jr on 427" will have more low end torque and throttle respnse than you know what to do with on anything short of 14" wide slicks.

That thing should blaze the tire from a 20 mph roll in second gear on any kind of regular street radial, even 325mm wide tire....should even blaze a Drag Radial on unprepped pavement. That isn't that big of a cam in a 427 " engine, it's not too big at all.

Trust Art Carr on the non-lock-up...there is a reason he was the pioneer on the use of the 200-4R that was stock in the Turbo Buick Grand /national in the 1980's, his stuff was fast and strong, guys were running in the high 8's at 145+ mph 1/4 mile with that trrans and converter from him.....he's forgotten more about the 200-4R than most have ever even learned.

To me it sounds like a cam insrtalled with the wrong keyway on a multi keyway timing set lined up with the wrong dot on the gear. Sounds like cam is badly retarded.

If everything was installed right, with that list of parts combined with the 2.74 low gear in the 200-4R and 4.11 rear gears that thing should light them up at will, and blaze them as long as you want to hold the pedal down.

It's not the carb, it's not the intake, and I'm 98% sure it isn't the converter...my money is something fundamental in the assembly process got missed. Cam degreeing, TDC mark/balancer verification, lifters set too tight, ignition timing off because TDC mark is incorrect, something along those lines.

With a timing light it is impossible to "be a tooth off" on the distributor....you just crank the distributor body around farther to get it timed to the crank again....the only time "a tooth off" comes into play is when you can't turn the distributor body enough , like the vac can hits the intake casting or firewall or the plug wires won't flex that far and it limits you from turning the distributor body far enough to get it into time.
A lot of guys just can't seem to grasp this fact.
To me it sounds like a cam installed with the wrong keyway on a multi keyway timing set lined up with the wrong dot on the gear. Sounds like cam is badly retarded. I suspect this as well
 
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