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  #31 (permalink)  
Old 08-08-2012, 11:41 AM
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between spin and bb427 you can see the engines did not change that much.So,adding a cam/manifold/carb/headers should put you north of 300 engine hp and a nova,especially 68-70 will hook well with good tires.I dont see why it wont go 13 something unless the owner/driver has the whole car messed up. I know I could go 13s with a car like that with a low CR 400,even with 2,73 gears.not the best combo but do able.

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  #32 (permalink)  
Old 08-08-2012, 01:32 PM
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PG's have either a 1.82 or a 1.76 first gear, where a TH350 has a 2.54 first gear. With the high rearend gears, and the cam, it wont even begin to make power until he's already through the 1/4 mile traps. It would be like trying to start your car down the 1/4 in third gear with a stick and 2.73 gears. If it wasn't for the torque converter it would kill the engine when you launched!
It really doesn't matter if the engine is 400ci and makes 350-400 hp, if it's nowhere near that HP range when he's trying to finish the 1/4. I'd guess with his trans and rearend gears he'll never get out of 1st gear in the 1/4 mile.
If it had a TH350 it would help a lot, but a set of gears in the 3.42-3.73 ratio, and a TH350 would make it a screamer in the 1/4.
13's are way out o the question. My stock 390hp 427, with 3.42 rear in my '71 Camaro ran in the 13's when I first ran it back in the early 70's. After changing cam and intake, adding headers, and different set of tires, plus a shift kit, I got in into the 12's and occasionally into the high 11's. 13 sec. quarters are not that easily obtained, and everything is against this car getting there.
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  #33 (permalink)  
Old 08-08-2012, 01:50 PM
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427 is 27 cubes bigger than 400.If your camaro ran 13s then a 400 nova which should hook better can run 13s.The 3 spd issue has already been covered.
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Old 08-08-2012, 01:53 PM
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Quote:
Originally Posted by vinniekq2 View Post
427 is 27 cubes bigger than 400.If your camaro ran 13s then a 400 nova which should hook better can run 13s.The 3 spd issue has already been covered.
Please tell me how a engine with 27 less cubic inches, a PG trans, and a tall 2.73 gear runs faster than a engine with more torque, ci, lower rear gears, and lower first gear?
In what dream world do you live?
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Old 08-08-2012, 02:01 PM
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I didnt say faster,,,If your rat camaro that weighe 200 pounds more making 390 HP can run 13s,I say a similar sized engine maybe making 30 less hp in a 200 pound lighter car can also run 13 something. again I quote.Mike McFaddens car
86 monte 400 long block from bond mechanical,273 gears 3 spd auto,street whitewall tires, sig erson TQ20 cam,small tube headers, carter 4bbl al intake,14.1s
to go 13s,better tires,more cam

My 305 firebire(83 5 spd) went that fast .
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Old 08-08-2012, 02:31 PM
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I give up.
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Old 08-08-2012, 03:23 PM
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used wrong diff gear set for figures

Last edited by vinniekq2; 08-08-2012 at 03:36 PM. Reason: mistake
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  #38 (permalink)  
Old 08-08-2012, 03:39 PM
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2.73 gears could possibly take you through 1/4 in low gear in PG with 2.73 gears.top speed in low gear would be in the 90s.
TH 350 would likely go through in second gear. 1-2 shift at 60 mph
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Old 08-09-2012, 09:03 AM
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So after thinkin if I want tht ****ty summitk1107 488/510 cam. I'm pretty sure ima go buy a new cam where I won't have 2 change 2 much of the stock springs and valvetrain components. I kno the 400 doesn't see rpm way 2 high up so a small cam probably will work better. Ima go start lookin atop of the ones already suggested.
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Old 08-09-2012, 09:20 AM
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black,think of your engine as a swimming pool.You need to fill the pool with water.You have a garden hose to fill the pool. Do you want a bigger hose to fill the pool or do you want mote time to fill the pool?
cam duration is time,valve lift is the hose size.
there are other restrictions to consider,,,port volume/port velocity,carb size, etc.low RPM does not mean the cam has to be smaller. Maybe shorter duration with more lift.

also think about too big of cam like filling a fish bowl with a fire hose. too much and most of the water is spilled and the fish bowl doesnt get filled properly either.Its a mathematical formula.If you do make an error,its probably better to have a cam thats too small.
remember a cam is just 1 of many parts that need to work together
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Old 08-09-2012, 10:44 AM
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[QUOTE=my87


change the heads or keep your power goals very low, like 230hp/300tq ish which in a 3200-3400lb nova and the trans and gear should have you running about a 16 in the 1/4. sorry[/QUOTE]

I'm fairly new 2 hotrodding but this ^^^^^ is some bullshidd. . I had a 307 4 my yeah 200hp 300trq and it ran 16.91. 2 barrel carb stock cam stock everything. You tryna tell me a block with almost 100 more ci is gonna do the same? Gtfoh
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Old 08-09-2012, 10:59 AM
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Quote:
Originally Posted by vinniekq2 View Post
black,think of your engine as a swimming pool.You need to fill the pool with water.You have a garden hose to fill the pool. Do you want a bigger hose to fill the pool or do you want mote time to fill the pool?
cam duration is time,valve lift is the hose size.
there are other restrictions to consider,,,port volume/port velocity,carb size, etc.low RPM does not mean the cam has to be smaller. Maybe shorter duration with more lift.

also think about too big of cam like filling a fish bowl with a fire hose. too much and most of the water is spilled and the fish bowl doesnt get filled properly either.Its a mathematical formula.If you do make an error,its probably better to have a cam thats too small.
remember a cam is just 1 of many parts that need to work together
Pure WISDOM (in a different sense) 4rm someone with the same name as me I believe. .

My thing now 2 anyone tht can help. I'm keeping the motor fairly simple. Give me a BANGIN CAM THAT A STOCK HEAD STOCK BOTTOM END 400SBC WILL LOVE.
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  #43 (permalink)  
Old 08-09-2012, 11:04 AM
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Panther, you need to listen to what these guys are saying. The stock heads are going to kill your build. You need to at least do some porting and get the compression up. Also, you need to change your gears. Was it 2.73s you have? With those gears and the powerglide you'll finish the 1/4 with the engine spinning 4000 rpm. It's just not a good combo for drag racing.
You need to get 3.73's at least. Check your PM's i'm sending you one right now.
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  #44 (permalink)  
Old 08-09-2012, 11:11 AM
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in a 400 ci sbc with a decent 4bbl and open plenum intake you can use any brand name camshaft with 465 ish lift and 225 duration at 050.if you want more bottom end then look for the intake centreline around 104 to 106,,,more top end 108 or 110 icl. these are just starting point numbers. read the catalogue,talk to the tech line and remember a 400 can use 1 size bigger than what the page says because most pages are for 350 ci sbc. a 5500 rpm cam will make your 400 sing to 5k.
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Old 08-09-2012, 03:00 PM
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225 @.50 is way too much duration for a stock engine on the stock converter with highway gears.

Panther, here's the cam i have in my car. I have a mild 350 with 9.5:1 compression. I still have stock converter and highway gears also. It performs very very well off idle and pulls hard all the way to 6k. You can try to find something similar if you want name brand but i'm very happy with my jegs cam. And for the price you can't beat it. If you want a bigger cam you can go to the next larger one they sell but no bigger or else you will need a converter. I still suggest chaging gears but this cam will work fine with what you have.

Cam: JEGS Performance Products 200102 JEGS Performance Hydraulic Flat Tappet Camshafts

Also remeber to run zinc additive in the oil when using a flat tappet cam.
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