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Discussion Starter #1
I am building a 77 nova street/bracket car and after doing some research i think i may have made the wrong choice on my heads? my basic combo, 77 nova aprox. 3200lbs w driver. Built th350,3500 stall 8.5 rear w/ 4.88 gears, short block balanced .030 350 4 bolt main, speed pro forged flat tops. stock rods w/ Arp wave lock rod bolts, stock cast crank, (rpm limit?) summit#1108 hyd flat tappet cam. Lift 542 intake/568 exhaust, dur 244 intake/254 [email protected] .050 lobe centers/ 109int/119 exh. Msd 6al -billet dist. blaster coil. 1 7/8 headman headers,w 3 inch exh. with x pipe summit chambered 3inch mufflers. heads are cnc ported alum. 64cc chamber 2.02/1.60 valves. straight plug. intake ports 200cc exh.70cc. Flow #s 269/[email protected] 275/[email protected] lift. (Intake Manifold yet to be determined any suggestions?) 650 holly DP/ edelbrock 750 or 800 Qjet? i have all three. Also will be adding a 150 shot of Niotrous. Will the 200cc intake ports kill my bottom end TQ. With only 9.5 compression? Would milling heads to raise compression help? Im on a very tight budget right now so this is what i have to work with. I am a veteran Et racer But raced true Pontiacs getting back into the game and new to sbc combos so any help or advice would be greatly appreciated! Thanks
 

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I am building a 77 nova street/bracket car and after doing some research i think i may have made the wrong choice on my heads? my basic combo, 77 nova aprox. 3200lbs w driver. Built th350,3500 stall 8.5 rear w/ 4.88 gears, short block balanced .030 350 4 bolt main, speed pro forged flat tops. stock rods w/ Arp wave lock rod bolts, stock cast crank, (rpm limit?) summit#1108 hyd flat tappet cam. Lift 542 intake/568 exhaust, dur 244 intake/254 [email protected] .050 lobe centers/ 109int/119 exh. Msd 6al -billet dist. blaster coil. 1 7/8 headman headers,w 3 inch exh. with x pipe summit chambered 3inch mufflers. heads are cnc ported alum. 64cc chamber 2.02/1.60 valves. straight plug. intake ports 200cc exh.70cc. Flow #s 269/1[email protected] 275/[email protected] lift. (Intake Manifold yet to be determined any suggestions?) 650 holly DP/ edelbrock 750 or 800 Qjet? i have all three. Also will be adding a 150 shot of Niotrous. Will the 200cc intake ports kill my bottom end TQ. With only 9.5 compression? Would milling heads to raise compression help? Im on a very tight budget right now so this is what i have to work with. I am a veteran Et racer But raced true Pontiacs getting back into the game and new to sbc combos so any help or advice would be greatly appreciated! Thanks
I would like to see compression greater than 10:1 with that cam and 200 intake runner on a 350.
you might be okay because you have a 3500rpm converter
you could have the heads milled.
I like about a 750dp. quick fuel
plan to drive on street with that 4.88 gear? :eek::D
 

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Discussion Starter #3
Good question lol

Any suggestions Again depends on engine rpm limit and 1/4 mile time shootn for 6500 rpm through traps was thinking 3.90 to 4.11 then there is the niotrous to consider:D
 

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Discussion Starter #5
More about your combo?

Curious about your intake/carb. and rear gears. Was is streetable? Thanks Kevin.
 

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seems like with those specs, vortec heads might be worth looking into on the 350. All those specs would look a lot better on a 383 short block imo. The biggest thing that concerns me with your combo if you plan on racing, especially if you're spraying 150-200 is the stock cast crank and rods :eek:

one of the biggest questions in my experience drag racing, is to be honest with yourself about your intentions. Will it be street or race? because both is pretty difficult to accomplish successfully. (you make adjustments to go faster at the track and it becomes less street able, make changes to be more street able and becomes a dog at the track...) In my experience my best racing/steetable combo was my 350 with performer rpm cam and intake with vortec heads, TH350 and an 8.5 10" with 3:73 gears and an eaton posi ran 12.50s very consistently and with spray would go into the 11s. IMO if you're spraying you should be using forged stuff or you're asking for trouble.
 

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I thought this was going to be a discussion of "Big Head" vs. "Little Head" doing the thinking. :devil: :rotfl:
 

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Discussion Starter #8
Mostly ET racing/very limited street use,

This is exactly why I am asking for advice and thank you! I plan on running Lucas oil raceway points ET class. and limited local cruise ins, Nos will be for wed night grudge racing, Class yet to be determined Based on my cars et. since points are my goal reliability is my # 1 goal. This combo is what i have to work with, will upgrade as money permits, gear choice is a major factor and suspension and traction upgrades will be addressed long before nos is considered. Im sure my 60ft will suffer with these heads but ok with me if the car hooks and is consistant. your advice on a safe rpm limit for the rotating assy. will help me determine gear choice Thanks again Kevin
 

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Discussion Starter #9
big/little head

The older I get The more the big head has taken over!:rolleyes::thumbsup:
 

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Discussion Starter #10
461s?

I have a Fresh pair of ported and polished 461s available or dart iron eagles i may be able to swap my heads for?
 

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I have a Fresh pair of ported and polished 461s available or dart iron eagles i may be able to swap my heads for?
I built a 355 for my daily driver truck and put the iron eagle head on it and I will say that I like them.

im building a forged 406 right now and need to find another set of heads for it so I will have to make a head decision soon as well
 

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I built a 355 4-bolt main once using the stock crank, stock rods and 11-1 pistons that I picked up from a swap meet new for $150.. Cam profile was 260 @ .050 with .555 lift and 1.6 rockers. Intake was a victor jr topped with a 750dp holley with 50cc acc pumps (the only mod). First I used a heavily modified set of camel backs and the car went 11.90's. I then swapped them out for a set of Iron Eagle 200cc with no modifications and the car went 11.30's and then I sprayed it with 150 and went 10'80's.. This was in a all steel 73 Camaro with 4.56 gears, 4000 stall and footbrake launch.. If the car is tuned well, 150hp shot will usually knock about 1/2 second off a 1/4 time.

Sell the 461's to a street rodder, you will never get them to flow like a decent out-of-the-box set of heads. If I was on a budget I would sell what I could to get a good set of heads, angle mill them to get your compression up and you should have a nice mid 11 second car with no spray. If you already have the Iron Eagle heads, that's a good start, they are good heads. The Quickfuel carbs are great out-of-the-box carbs..
 

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Discussion Starter #13
thanks

everybodys input has been extremely helpfull, sounds like compression we be the key to use my current heads. i have not done the actual math on my comp. ratio, only what is advertised, Speedpro Forged Flat tops 030 w 64cc heads = aprox. 9.51 comp. ratio. anybody know aprox. how much i would need to have the heads milled to get to aprox 10.5 ratio? thanks again!!
 

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everybodys input has been extremely helpfull, sounds like compression we be the key to use my current heads. i have not done the actual math on my comp. ratio, only what is advertised, Speedpro Forged Flat tops 030 w 64cc heads = aprox. 9.51 comp. ratio. anybody know aprox. how much i would need to have the heads milled to get to aprox 10.5 ratio? thanks again!!
The general rule of thumb is to flat mill .006" per 1 cc. You have to have cylinder volume, combustion chamber volume, piston valve relief volume, head gasket volume, ring land volume, and deck clearance volume to calculate compression. Just using round figures, a .030" over 350 cylinder has 727.4 cc's of volume, plus 64 cc combustion chambers, roughly 6 cc's for valve reliefs (flat tops), 4.2 cc's for piston to deck clearance (pistons roughly .020" in the hole), 8.4 cc's for your head gasket, and 1.1 cc's for ring land volume, leaves you with a static compression ratio of approximately 9.69:1. Dividing unswept volume by swept (811.1/83.7) gives you your compression ratio. To get close to 10.5:1, you're would have to flat mill your heads .042" (7 cc's). It would be really tight to flat mill most heads and not run into the intake valve seat on the shallow side of the chambers, so most machine shops use a combo of flat and angle milling.
 

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everybodys input has been extremely helpfull, sounds like compression we be the key to use my current heads. i have not done the actual math on my comp. ratio, only what is advertised, Speedpro Forged Flat tops 030 w 64cc heads = aprox. 9.51 comp. ratio. anybody know aprox. how much i would need to have the heads milled to get to aprox 10.5 ratio? thanks again!!
I was thinking a full flat top w/64 cc head would get you higher than that?
 

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I am building a 77 nova street/bracket car and after doing some research i think i may have made the wrong choice on my heads? my basic combo, 77 nova aprox. 3200lbs w driver. Built th350,3500 stall 8.5 rear w/ 4.88 gears, short block balanced .030 350 4 bolt main, speed pro forged flat tops. stock rods w/ Arp wave lock rod bolts, stock cast crank, (rpm limit?) summit#1108 hyd flat tappet cam. Lift 542 intake/568 exhaust, dur 244 intake/254 [email protected] .050 lobe centers/ 109int/119 exh. Msd 6al -billet dist. blaster coil. 1 7/8 headman headers,w 3 inch exh. with x pipe summit chambered 3inch mufflers. heads are cnc ported alum. 64cc chamber 2.02/1.60 valves. straight plug. intake ports 200cc exh.70cc. Flow #s 269/[email protected] 275/[email protected] lift. (Intake Manifold yet to be determined any suggestions?) 650 holly DP/ edelbrock 750 or 800 Qjet? i have all three. Also will be adding a 150 shot of Niotrous. Will the 200cc intake ports kill my bottom end TQ. With only 9.5 compression? Would milling heads to raise compression help? Im on a very tight budget right now so this is what i have to work with. I am a veteran Et racer But raced true Pontiacs getting back into the game and new to sbc combos so any help or advice would be greatly appreciated! Thanks
There is nothing wrong with your heads. However, the cam is junk. I have personal experience with that cam, in a combo really similar to yours, in a friend of mine's 76 Nova. 355, 11:1, ported 041's (Fuelie heads), your cam, Performer RPM, 750 double pumper, 1 5/8" headers (2 1/2" full exhaust), Turbo 350, TCI Super Street Fighter converter, 4.88's, and 28x9's. Went 8.20's in the eighth mile. He swapped over to a Competition Cam's 294 solid, which wouldn't have been my first choice, and went 7.80's, with no other changes. A 150 shot put him in the 7.20's.
 

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In the combo we did it was run on the street on pump 93. It had a t-400 with a transbrake and a 4.56 gear. At the track I would bump the timing up and put 110 in the tank to be safe. It was driven quite a bit. It was an ultradyne 251/251 @.050 solid flat tappet, somewhere in the .530/.550 lift. It was quite a few years ago, but it went 1.58 in 60' and 11.50's in a mostly stock appearing 69 camaro.
 

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Discussion Starter #18
cam choice?

I am very encouraged by all of the response! I had an original goal of 11s on motor, and it sounds like i might be going in the right direction. if cam choice is the key to making this combo work i should have asked you guys a long time ago. any suggestions? my springs are good to .575 lift and I have 1.6 ratio alum roller rockers. cant afford roller cam at this time. and if i go solid would oil restrictors be recomended Thanks again!!
 

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I am very encouraged by all of the response! I had an original goal of 11s on motor, and it sounds like i might be going in the right direction. if cam choice is the key to making this combo work i should have asked you guys a long time ago. any suggestions? my springs are good to .575 lift and I have 1.6 ratio alum roller rockers. cant afford roller cam at this time. and if i go solid would oil restrictors be recomended Thanks again!!
Don't run oil restictors on a street driver. You need to cool the springs on a street driver. I wouldn't go too crazy with lots of lift for reliability's sake. For max torque and power in your rev range, I would go with something on a 106-108 LSA. The Competition Cams 280b6 works really well in a 350, with a 3500-4000 stall converter.
 

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The heads are fine, stay with the aluminum. If anything, shave a little off and bring the comp up to a 10-1 if possible

The cam, maybe, Is that the spec with the 1.6 rockers or the 1.5 rockers.
WE run a few of the Lunati cams and we like them for an out of the box cam. You might make better power with a bit smaller cam with that comp. My 406 has the Lunati 515/515 and ran 11:70 in my All steel Heavy 55 Chevy sed del before we put it into my daughters 69 Firebird. Then it went a steady 10:40 in that. Her 69 F/B is 2750 lbs, 400 trans @ the time and a 4:30 gear 29 tall tire, 750 holley and All motor. And she runs a 485/485 Lunati in her street trim 75 T/A 350 SBC, around a 12:1 motor, 64 cc Edelbrock out of the box head, small 2800 conv, and a 4:10 gear, HEAVY car. And it will go 12:50 all day. The 12-1 was by accident. Got the wrong pistons from the machine shop when i was building it, but had a time crunch to get her to her first race @ 16 years old. So we stayed small cam with the big comp and it runs flawless. We use to run it every where ,it was crazy good on gas and VERY dependable. She's 31 now and that old 350 Chevy motor still runs like day 1. And it's got well over 300 passes on it and some decent street time.

The gears, i think are going to be WAY too much. I'm thinking 4:30's or 4:56 @ the most depending on >> What size tire are you running ?

And you'll need to get the converter set up for the spray.

And run the 750 carb , & maybe try the 50cc pumps, might help, especially with alot of gear if you stay that route. Worth a shot

I hope i didn't rattle on too much. Hope you can use some of the info. Good Luck this season. And your Pontiac buddies are going to hate you. They hate use for putting the Chevy's in the Pontiacs. LOL
 
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