I am at a cross roads and need some help here. I bought my '69 a year ago with a fairly built 402. I have no idea yet what is under those heads but it's getting almost time to beef things up. I hear rumors of 750+ HP 396/402's that aren't blown. Is that true and what combos do you have to make good power for these motors? Oh-Ya, Going to a bigger block is not part of this equation.:rolleyes:

Frank,I doubt you'll find any "true" 750 HP n/a 396-402's
A stout but very streetable 396 IMHO would be solid lifter cam in the 240ish @ .050 range on a 110 LSA ,have at least 9.5 to compression and if you choose to run stock castings,a good port job and some chamber work would be the order of the day.
With a stick car car,3.73's and a 2.88 1st gear ST10 would be a fun drivetrain with a motor like that.

I don't think there are going to a lot of 750 hp 396's. I think more realistic is a 500 hp goal. Mine is a 408 at a reasonable cost made 501 hp.

That's what I expected to hear. So what are you guys doing to get a 500+ 369/402?? Heads, Cam, Compression?????

402=.060, 9.8 comp ratio
Rectangle port heads(engine owner still thinks these are better than ovals)
Engle roller cam .650/.653 256°/264°@.050
Edelebrock singleplane w/750Dp
Engine made 460/470hpNA and 670w/a 200hit runs 11:20's 118mph NA&10 flat@134mph so far on juice in a 3700lb 1970 velle

8" Ati converter,4:10 or 4:56's

402=.060, 9.8 comp ratio
Rectangle port heads(engine owner still thinks these are better than ovals)
Engle roller cam .650/.653 256°/264°@.050
Edelebrock singleplane w/750Dp
Engine made 460/470hpNA and 670w/a 200hit runs 11:20's 118mph NA&10 flat@134mph so far on juice in a 3700lb 1970 velle
is that 460hp at the rear tires? that's pretty stout if it is.

Thats flywheel horsepower listed.
I'm not sure how much rwhp it has maybe 400 or so..

I have a 70 Velle and run high 11's. What gears are you running? I'm trying to work things out for my setup,

Thanks

Moonbeam- What motor setup are running in your '70?

Thats flywheel horsepower listed.
I'm not sure how much rwhp it has maybe 400 or so..
i think you must've tuned in some more power since the dyno runs. seems impossible for a heavy chevy to run 11.20's with only 460hp to the flywheel. maybe i'm out in left field with my thinking on this but i figured it would take well over 500hp to run low 11's in a Chevelle.

Race Weight w/ Driver ~ 3600 lbs

Engine
402 BBC
L88 forged crank
TRW Forged Pistons (9.75:1)
Eagle I-Beam rods
GM iron oval port heads (Casting # 3904390) with Manley valves (2.06 Intake/1.72 Exhaust) Bowl Blending, and 3-angle valve job
Crane Gold roller rockers
Competition Cams Xtreme solid roller cam XR274R(236/242 @.050, .639/.646 lift, 108 LSA)
Crane roller lifters
Stock L88 pushrods
Edelbrock RPM Performer intake
Holley HP750 Double Pumper Carb

Exhaust
Hedman 1.75 in. primary headers with Flowmaster Scavenger collectors. 3 inch pipes with 3 in. H-pipe into 3 in. bullets dumping right before the rear axle housing.

Rear end
12 Bolt with 4.56 gears
Moser 30 spline C-clip eliminator race axles

Trans
TH400 with full reverse manual valve body
ATI 8 in. converter flashes to 5000

Ignition
Stock rebuilt HEI distributer
MSD 6AL box
MSD Blaster coil
Holley plug wires

Performance

Best ET to date @ Piedmont Dragway:

60Ft. - 1.538
330Ft.-4.607
660Ft.-7.220
MPH - 94.50

Chad- Great '67...Nice times in the 1/8 too.
That's what I'm looking for...good combos and helpful information.
I knew this site isn't ruled by only 427/454 guys:thumbsup:

i think you must've tuned in some more power since the dyno runs. seems impossible for a heavy chevy to run 11.20's with only 460hp to the flywheel. maybe i'm out in left field with my thinking on this but i figured it would take well over 500hp to run low 11's in a Chevelle.

I guess you figured incorrectly cause the tune on the engine is the same as the dyno.
They gotta 60ft well to et well. This velle 60's are in the 1.55 area.
I think Todd Geislers car put down 420@ the rear wheels and he was turnin 10:70's or so.

I guess you figured incorrectly cause the tune on the engine is the same as the dyno.
They gotta 60ft well to et well. This velle 60's are in the 1.55 area.
I think Todd Geislers car put down 420@ the rear wheels and he was turnin 10:70's or so.
i guess maybe that's differences in dynos or something. my 406 makes right at 370RWHP which is like 440hp to the flywheel and i only run 11.80's with a 1.55 60ft. as far as Todd's car goes, it is a couple hundred pounds lighter than a Chevelle and 420rwhp is usually over 500hp to the flywheel.

Guys- what kind of gears are you all running to get those times and what trannies?

I can't believe that there are only 4 guys on this whole website running 396/402's :clonk: ;) :clonk:

I can't believe that there are only 4 guys on this whole website running 396/402's :clonk: ;) :clonk:

..if you use the search function,and type in "396 combos" you find plenty of info.

http://www.chevelles.com/forums/search.php?searchid=651205

Frank, first thing you need to do is identify the heads you have. If they are open chamber heads, you are lucky to have 8.5/1 CR, maybe mid 9.5/1 if the motor has the large dome pistons , but highly unikely. Get some details on what you have now listed. Two things that will help (if you do not know any particulars about the motor) are cranking cylinder pressure and vac at idle. Pull a valvecover and get the #'s off the head while you're at it.

My heads are 950's Oval port 109cc but honestly, it is a 50-50 split on web sites if they are open or closed chamber.

69 L78 block is .30 over have 840 rec port 105 cc heads next size up on SS valves,comp cams 290 roller cam,pro magnum roller rockers & roller lifters, "8 ati super damper ,750 mitey demon, KB pistons aprox 9.75/1 CR makes 470 flywheel horse @5900 rpm & 450 lbft torque@4800 rpm. Its a 4spd car with 3.73 gears & is a blast to drive

My first was supposed to be in the 500hp range,e.t.s told a different story.Had a poorly mixed up pair of heads on it,amongst a couple other things,guessing it really had 350hp at the flywheel.Big dissappointment.That was a .030 396,the crank,rods and pistons are now in a 402 block with a good set of heads and intake,hoping to get around 500hp at the flywheel.Machine shop guestimates around 525,desktop has it about the same,so I'm expecting about 480 in real life.

i think you must've tuned in some more power since the dyno runs. seems impossible for a heavy chevy to run 11.20's with only 460hp to the flywheel. maybe i'm out in left field with my thinking on this but i figured it would take well over 500hp to run low 11's in a Chevelle.
According to this calculator (http://www.slowgt.com/Calc1.htm#HpWtSpd) He's dead on 468hp

Thats cool mine also came out @11.20 i would love to run it once but after all the money ive poured into it i'm kinda scared to beat the krap out of it on the track just content to romp on it every now & then on the street,,probably cost me 5 bucks every time i mash the pedal oh well its worth it

I haven't got it running yet... but I can tell you, it doesn't take much to make these engines run good. Mine is a

396 block, .030" over
Speed Pro forged domed pistons,
9 to 1 compression

288AR solid Comp roller camshaft 2200-6500 rpm

049 open chamber head
788 open chamber head
2.19/1.88" stainless valves, milled, bowl blended
1.7 Erson roller rockers

Professional Products, dual plane, high rise, air gap intake
800 double pumper Holley
Generic new HEI distributor, with high voltage coil

1 7/8" headers, with 2 1/2 in exh, Dynomax Super Turbos

I am guessing the motor will be around 400 hp at the flywheel.
I am going to change the heads to closed chamber, same valve arrangement next year, I would guess the added compression would probably put me closer to 450.

Oh and the next funnest part is this is in a 69 Camaro behind a beefed up 700 R-4, 2800 stall, and 3.90's. I am hoping for 11's in the near future.

500 horse sounds great, but it depends what you're doing with your car!
How many street driven cars get revved to 5 grand on a regular basis?
These are the thoughts I kept in mind when building my 396.
I took note of a buildup they did in Car Craft of a 66 396

Their engine in the test only made about 380 HP @ 4900
but torque came in at 456 ft lbs @ 3300 !
Torque moves mass. Its the torque you feel when you let 'er rip !

Engine
67 396 + .060 = 408 cu in
KB 9.75 Pistons
Steel crank
Early dimple rods
Crane H 272
Closed chamber heads, 3 angle valve job, SS valves, CCd for each cylinder
Edelbrock Performer Intake
Holley 780 with vac secondaries ( 3310 )
Hedman 1 3/4 primary headers

My engine builder tweaked it a bit ( compared with the test engine) with the KB pistons 9.75 pistons .060 over. Timing is 16 BTDC at idle, total timing is 42 BTDC. I MUST RUN at least 94 octane gas! 91 with octane booster does not quite cut it.

Transmission
TH 400 ( rebuilt )
PAE 4000 switch pitch convertor ( 4000 rpm flash stall with hi stall on, 1200 with hi stall off )

Any hi perf engine needs a manual transmission or an automatic with a hi stall convertor for any kind of driveability. I picked my setup because it cuts down on the heat generated from a high stall convertor significantly. Once its launched, the stall speed is back down at 1200 since the solenoid in the trans. is hooked to my brake lights. All in all this is the best money I spent on the drivetrain!


Rear end
12 bolt posi
2.56 gears

This is the one thing I would maybe change, but the gas mileage is hard to beat 16 city/20 highway. Car will still light the tires with 4 people in it no problem.
No quarter mile times but I will keep you posted.

I have had a few 454 cars in my time and none could touch this one. Why? Because ALL the components are designed to work TOGETHER within a given operating RPM range.

Thats what makes all the difference. Plan it out so it will do what you want it to do BEFORE you start building it up and you wont be disappointed.

Good Luck and be patient!

According to this calculator (http://www.slowgt.com/Calc1.htm#HpWtSpd) He's dead on 468hp
not when i figured it...460hp + 3700lbs= 11.55@117 and that would be best case scenario with a very efficient drag car, not your typical streetcar set up.

I believe that calculates wheel horsepower.

well my 69 chevelle ss has a 402 ..and took the motor to a pro builder asked for it to be built equal to a old corvette 427 he said he could had it done for 4500 dollars.
seems strong but not sure id do more than mid 13's in quarter mile..also having trouble with it puking on 5 grand launches dies but starts right back up everything new not sure yet.4 speed t-10 373 gears 12 bolt 3 inch exhaust. 2 inch super comp headers.In the early 80's would have been a super fast street car but not nowadays everything 500+ so i just enjoy what i have...Its no merlin ..lol