I have this thing about wanting my engine to have at least 1 HP per cubic inch. And I want to keep it under the hood. I just got the car (66 chevelle) and the engine is mostly stock, haven't dynoed it yet but am guessing around 320 HP currently. I am just starting mechanic classes, but I have a lot of people to help me out. What exactly would you recommend to make this rat scream?

depending on what you want to do, a new cam intake carb and a nice tune should get you right up there no problems.

If it's a 325HP motor a new cam will make a completely different motor out of it. The stock intake isn't that bad for a mild street motor.

Originally posted by Spiku:
What exactly would you recommend to make this rat scream? Grab his tail. :D

build it like my 396.........it putting down right at 356 hp to the rear tires......which puts it well above the 400-425 hp mark at the flex plate.........and this is thru full exhaust as well......

my 396 is strong enough to push my 3900lbs camaro to 105.454 mph thru the 1/4 with the proper gears in this car it is easy 12's......very driver friendly ......13" of vacuum at idle.......easy to start.....runs on 87 octane and gets a honest 15 miles per gallon with a few hard runs in there to boot......

with alittle more tunning i should be about 107 mph thru the traps maybe more just in tunning carb and timming......

Headers,cam,intake,Holley and you're there,,,piece of cake with a big block smile.gif

I had my 396/325 redone at Dougan's Racing Engines in Riverside CA. They offered a formula that pretty much replicated what a lot of TC members' advice was back when I asked the same question.

My needs were for a completely stock-looking 396/325 that didn't have an too rough of an idle, loss of vacuum for the brakes, or need for more than 91 octane. Still, I wanted it to roar as much as it could within those confines.

What I got is what amounts to 375 horsepower under the hood through stock intake and exhaust on 91 pump gas. Dougans' performed the detailed block milling, boring, and assembly with the same nurturing they give to their race customer's engines, and also cleaned up the heads a bit in the bowls and turns. It went .030 over on the bores with milled-down 427 pistons, .010 on the crank, new stock rods and crank, and I got a trick valve job out of it along with some rocker/spring components and some intake manifold-to-head work.

It's using a tuned Quadrajet with a Pertronix trigger in the recurved distributor, Dougans' recommended plugs, and 2.5" stock exhaust with a gutted heat riser. All in all, this mill is supposed to rev quite a bit more than the stock 396/325's specs.

I'm hoping that my motor will roar pretty well compared to some of the meaner 396 engines of the '60s. If the old girl runs 14s in street trim, I believe that I'll be satisfied. If it ran 13s, I'd wet myself.

Headers and intake would probably make that 400 horsepower figure you're wanting, but I'm sticking with the bone-stock look.

Best thing you can do is to get the heads done with larger 2.19" and 1.88" valves and pocket ported or buy a set of oval port Merlins. A cam, carb, Performer RPM intake and headers with 2 1/2" pipes should get it easily.

Grind the raised Edelbrock,Holley off the intake,paint it orange and noone will be the wiser. smile.gif

No more then a stock, 325hp/396 with the 110/106 centered, Isky 280 Mega cam, a good old 750 Q-Jet or 3310-2 Holley and needed RPM intake and a set of 1.75" four tube long headers should make 400hp or even a schosh more!!

But she has to be up around the stock 10 to 1 CR. to run best.... Sucker will get right up AND talk to you!!

Word of caution, use the valve springs that the cam manufacturer says to use!!

pdq67

I have never seen any dyno comparison but seat of the pants feel there is no difference between the early iron hirise and the performer rpm.

Good post, I am researching this type of thing myself.

Originally posted by Bob Tiley:
Best thing you can do is to get the heads done with larger 2.19" and 1.88" valves and pocket ported or buy a set of oval port Merlins. A cam, carb, Performer RPM intake and headers with 2 1/2" pipes should get it easily. It has been suggested to me (by others and from past post searches here) that bigger valves may not be as useful on smaller CID BBCs with closed chamber heads considering you may have to fly cut the pistons, and you may risk coming very close to water jackets. If you can get by all that, certainly the extra breathing capacity would be helpful.....

Open to commetns on that, I am still learning.

Using merlin heads is a good idea, 2.19 or 2.25 intakes with 1.88 exhaust. Pick a cam that will have all the power in by 5500 or so. It will make tons of bottom end and idle well.400 hp easy.450hp with a roller.
graemlins/thumbsup.gif
Mine made 541/590(no spray) at the flywheel with 9.2 to 1 and .534/.541 230/236 (?comp nitrous roller)and Merlin Heads...idles like a pussy cat graemlins/boring.gif

13's w/ hydraulic cam mild 396 motor: which pretty much equates to 380-400Hp flywheel in a 2 ton '69 car, nothing like real world testing.

396 + .060 = 408CI
TRW L2354+.030 (19.8CC), Piston/Deck = .014
.041 Head gasket, Final CR 9.5/1
'290 Oval ports w/ 2.19/1.72's , basic bowl work and clean up in both int and exh ports and a little extra relief around the guides on the exh side. Chambers relieved and polished, CC'd at 104
Edel Performer 2-0 (weak link #2)
Holley 770 Vac Sec.
Summit HEI
Crane 286 Powermax (286/296, 226/236, .535/.551 on 112LSA)
Hedman 1.75 Elite into 2-1/2" mandrel exhaust

T400 w/ 3000 stall

12 bolt, 3:73 w/ Eaton Posi

BFG Street Radials (WEAK LINK NUMERO UNO), good looking and decent handling for around town and highway cruising - don't waste your time trying to run these at the track unless you can deal with 2.25 - 2.45 60' times on part throttle.

Front Sus.: Hotchkis 1" low sprgs, w/ 1/2 coil
cut, KYB shocks, 1-1/8" sway bar (connected). Front springs have since been changed back to blasted and painted 35 year old factory big block springs

Rear Sus.: Replacment coils of unknown origin - but the ride ht is good, with a decent ride. Hotchkiss lowers, stock GM reinforced uppers w/ new rubber bushings, 3/4" (or 7/8" not sure) rear sway bar, KYB's. No wheel hop and now with the front end moving the car at least goes straight when it spins the tires.

When I finally took the time to run this car, it only took 2 runs to figure out what has to be changed to make it go. This setup will propel any 2 ton fully equiped car into the 13's with ease. Haven't been back yet, but I am positive that with the few changes I made to loosen up the suspension, some tuning (still running the out of the box carb setup) and a set of decent drag tires this car has a full second or better in it. At worst 13.2's - 13.3's, possibly even 12.90's.

Hope this helps.