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Chinese buffet destroyer
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Discussion Starter · #1 ·
just wondering if anyone had gotten into the 9s with a 396/402. i currently have a 402 in my car with stock rods/crank with trw 10:1 pistons, slightly ported stock closed chamber heads with a fresh valve job, new lunati valve train 595;595 lift cam with 252/262 duration flat tappit cam. a single plane intake port matched and ported. a 750 hp carb. car weighs roughly 3300-3400 with me in it. its got a th400 with a brake, and goes to 3800 on the brake.

the car went 12.70 with the old valve train 525/525 hyd cam. and 10.90 on a .72 square in a cheater plate. i know with the new valve train, and head/intake work, it should go 10.50s. i'd like to get it to go 9.99 once.
even if it breaks it at the finishline. i am planning on running a 63/71 tuneup on her, where should i go from there?
 

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That's a tall request for a 396/402.
IMO, you need more compression, better heads and possibly a bigger cam yet, and a looser converter. Then the durability of the bottom end comes into play since it will need to rev.

What approx HP ratings do those nos jetting produce?
 

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Chinese buffet destroyer
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Discussion Starter · #3 ·
its seen rougly 175ish on the .72 jet. the other jets are a 150 shot. it cant get better heads for it, and even if i could, i wont cause i know its gonna break. i could get a sligtly better converter and leave at roughly 4k-4200 but dont feel like spending the money. just trying to get it done with what i have. i was thinking of spraying it with 250 but with my luck it would go 10.0 or something. and break.
 

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Chinese buffet destroyer
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Discussion Starter · #6 ·
well the motor orginally came out of a nova to my understanding and was a 375 hp model i think. with the cam that i've got, do you think that it's possiable? i really dont want to spend anymore money on a motor i know is gonna break due to the cast crank and 2 bolt mains, but if there's a few tricks that you think i can do,please let me know. what all are done to the Stock eliminator cars?

edit: the car ran those times with a stock hood and full weight. i am going to be adding a fiberglass hood, and also want to do fiberglass front and rear bumpers which should really help the car out weight wise. other plans for the car include a 10pt CM cage over the winter. it currently has a 4pt mild steel cage.
 

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The 375HP 396s had forged cranks, rods and pistons. Compression from the factory was 11.5:1
Rectangular port heads and a solid tappet cam.
Could spin to 7500 all day long.

In NHRA stock trim, the cam has been changed to up the performance.

AND their suspensions are a work of science. Right shocks, springs, gear, converter, ride height, etc. You say you don't want to spend any money now. Take a guess on what a top B/S 396/375 horse engine costs?
 

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One more thing, these 396/375 all came from the factory with 4-bolt main blocks.
 

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I had a 70 375 HP 402 which has from the factory a 4 bolt block, steel crank, dot rods, TRW forged pistons, closed chamber rec port heads so if you got a cast crank and 2 bolt block you don't have a real 375 HP motor. I blue printed that motor, changed the cam to a .630 lift solid FT cam, changed the intake to a single plane manifold, added a dual point dist and a good coil and headers. I ran a 10.90 index class with it like that in a 3000 lb back halfed Nova with 14X32 slicks. I ran it on the bottle for a couple weeks just for fun with a dominator and a home made 300 hp plate and it ran some 9.90s at 140 MPH but it killed stamped steel rockers and pushrods cause it turned up RPMs so fast you couldn't shift it fast enough. Those parts can't turn 8 grand and live long. You'd have to be real clever to run the number you want at that weight with the combo you described in my opinion. RM
 

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well the motor orginally came out of a nova to my understanding and was a 375 hp model i think. with the cam that i've got, do you think that it's possiable? i really dont want to spend anymore money on a motor i know is gonna break due to the cast crank and 2 bolt mains, but if there's a few tricks that you think i can do,please let me know. what all are done to the Stock eliminator cars?

edit: the car ran those times with a stock hood and full weight. i am going to be adding a fiberglass hood, and also want to do fiberglass front and rear bumpers which should really help the car out weight wise. other plans for the car include a 10pt CM cage over the winter. it currently has a 4pt mild steel cage.


my sbcwas 2 bolt main and I sprayed it with 275 all day long for years .

beebe's old sbc had a cast crank and we hit it with 275 all day long ( it broke a rod) you can hit cast cranks and 2 bolts with a decent shot you just have to be on top of the tune . don't let it detoniate (sp)!!!!!!!
 

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Cast cranks are faster than steel cranks in my experiences. I figured they are lighter. And I know lots of people who have sprayed cast cranks too. If you got a decent tune up it works OK. But a 375 HP engine did not have a cast crank or 2 bolt block. RM
 

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it can be done.
gm says 7600 rpm on stock 396 engine.
mine had slpayed center caps by mildon, stock steel crank
trw 10.82-1 compression 106cc 427, 425hp heads with porting
and 1.88 exhaust valves, comp ultimate pro street cam solid roller, victor intake and a 750 double pumper.
it made 609 hp.
 

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610 HP is going to have a tough time pushing 3400 lbs into the 9 second range. Add stamped steel rockers and 3/8 GM pushrods will not last long at 7600 RPMs and I speak from experience there. I agree it can be done with 396 cubes but not with the combo he has. RM
 

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610 HP is going to have a tough time pushing 3400 lbs into the 9 second range. Add stamped steel rockers and 3/8 GM pushrods will not last long at 7600 RPMs and I speak from experience there. I agree it can be done with 396 cubes but not with the combo he has. RM


X2
 

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your rite he needs more everything.
mine came in at 3240 after being backhalfed
from 3850 lbs
and ran 10.50's at 130 mph.
there's a lot more in the combo to run that fast.
 

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Chinese buffet destroyer
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Discussion Starter · #16 ·
well thats kinda a bummer. the compression on the motor as i said is somewhere around 10:1 maybe slightly higher, it runs ok on pumpgas. but has a large dome on the pistons. with the crane roller rockers and what i've stated i've got for valve train, how hight would you spin it? the pervious owner spun the motor to 7000 with the old set up. and what do you think a combo like this should run?
 

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Chinese buffet destroyer
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Discussion Starter · #17 ·
one other thing, the motors got crane gold race rocker arms.
 

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If you have a good converter and the motor runs well, at 3400 lbs I'd guess you'll be 11.20s no power adders in average air. Great air and good track it could run faster.
 

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Chinese buffet destroyer
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Discussion Starter · #19 ·
wow thats a LOT better then i figured it'd run, i wa hoping for maybe 12.0-11.90's on motor.
 

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You could be right. I am basing that on what I remember running a long time ago with mine. My rememberer don't work as good as my forgetter does. best of luck with it whatever it runs. RM
 
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