Thread: 402 needs more power (heads & cam)

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Hi guys, I'm Tim 22 yrs young and live in Switzerland.
Since 2012 I own a 68 camaro with bigblock and 4 speed. Now I'm installing a tremec tkp 600 trany.
And the project for the next winter should be the engine. The engine is a stock 402 bbc casting i think 3999290. Heads are cast iron. I can spend 2-3k$
I need advice how and specially what I have to do. I'm thinking about aluminium heads, and a hyd flat tappet cam. Pistons and crank are stock. I have headers (brand unknown), msd ignition, mallory distributor, edelbrock performer rpm intake and edelbrock 600 cfm carb. I also have one or two 750 holleys..
so due the price I prefer to let the crank and pistons stock. Engine is rebuilt 1000miles ago.
But now my questions is how high can I rev the engine with stock heads and pistons? I'm a bit afraid to rev it up like hell.. Rpm limit with new heads and cam?

Which heads do you recommend? I'm thinking about rpm performer or brodix rite ovals. Cam?
Should be streetable, power from low rpm.

I have never done this before, so I hope you could help me to choose the right setup.

Thank you so much!
And if you like I can ad pictures of my car

Aluminum heads and intake should be at the top of your list, and will give the best return on your dollar. Check racingjunk.com you might find some cheap.

you do not need new heads. them iron heads i used many times if engine is built right as for size of cam. i go hyd roller on bbc for street most all the time .a kit may be your best way to go for $$ . you do not have enough info on parts listed on your 402 to give me what way you can go .i need cr or piston numbers should be stamp in the piston to .as for rpm you only need to take the engine only were it is going to make power cam and heads intake carb cfm plays in to this . a well built stock bottom end bbc can take 6500+ most all the time with a good oil pan and damper. it not the bottom end that would stop you from hi rpm it is valve train build it right there is no need to take it this hi in rpms any ways with a 5 speed .what helps is a good machine shop/ parts source . getting back to the heads. if heads have been worked over and they do not need a lot of work just a multi angle valve job some bowl work good flowing valves if needing new valves and valve guids then at this time i move up to a 11/32 valve stem it helps some for alve train weigth and flow it not a lot but helps . i built many bbc using them heads . but if you have no engine shops were your at then new may be a better way to go at all come down to hourly rate to the cost of new heads

you should look at it this way them heads you have now i used them to feed bbc from 396 to 496 them heads with some work can make 500 hp easy .most all after market heads are built to feed a 454 and up . right now the stock heads are bigger then many heads you would put on a 400 small block . the 402 big block is just a heavy sbc just built better stock from GM .at the end of they day it still very small on cid for a bbc you just need to watch what cam and heads your going to buy as most all bbc heads are to big for build like this

Tim,
Welcome to CHR, and to answer your last question first, we'd love to see pictures of your Camaro. It astounds me how much American iron makes it to other parts of the world!
Pat's the guy on BBC's, and he knows what those stock heads can do for you. Like Pat said you really need to look at a roller cam vs flat tappet for reliability. An engine guy that I know well says that with a flat tappet cam it's not a question of if it will fail, but when (because they took the zinc and phosphorus out of motor oils to prevent fouling catalytic converters). And once you come back with some more information on your pistons/compression ratio the guys here can give you some options on a good cam and intake. Another option is to contact the tech line at Comp Cams, or one of the other reputable suppliers, and get their advice but they will also need to know your compression, the octane of the fuel you run in Switzerland, and how you intend to use the engine. I expect that a big part of your expense with parts is getting them shipped and imported, which is especially true for individuals who might be selling parts on the internet. Also, buying used parts is always a "buyer beware" situation, and from OUS it's even more true. Again, welcome!

Thank you for the warm welcome and quick response!

I checked again block is 3999290 and heads are 14081052. Any info about this heads?
How can I check my piston casting? Do I need to remove the oil pan? Or can I use a small camera trough a spark plug or oil drain hole to see the dome? I think my father have a tool to test the compression. Would this info be enough without piston casting?
Not far from here is a machine shop, but like everything else in Switzerland it's not cheap. So that's why I prefer new heads. My stock heads are also rebuilt and look good, so I prefer not to work on them.
Anyway I have also a 396 bbc engine in my garage but it's not assembled. Those heads are 3964290. I think they should be from 1970 396/402 with 100.9cc closed combustion chamber. One day I will rebuild this engine, but not now. So we could use these heads.

My goal isn't rev it up to 6500 rpm, but maybe higher than now. I haven't turned it higher than 4700 and i like the torque of this engine.
Do I need tall valve covers for full roller rockers?

And another question. I use a mechanical fuel pump but have a Mallory 140gph fuel pump and like to install it. Can i just use this pump with a pressure regulator without return or will this damage my pump? Should the pump switch of when there is enough pressure? On my dads sunbeam tiger can you hear the pump when you switch the ignition on but then it stops when there's enoug pressure. I think the pump delivers 12psi and my carb needs 6.5psi.

Thank you for your patience!
I like to work on my own car and learn how to do things

I was in january 2012 in San Francisco (first time in the states but definitely not the last time..!) We looked around for cars one for me and one for a friend. I searched for a mustang fastback or a camaro. So we found one without rust or tons of bondo, bought it and shipped it to Switzerland. Before the camaro I had a 97 Mustang Cobra.
An american classic car was ever a dream car for me and now I'm the happy owner of one and hope to keep the car my whole life

The photos are on my profile, I can't attach them tho this post.
http://www.clubhotrod.com/garage.php..._view&id=39261

Tim

Thank you for the quick response and warm welcom!

So how could i check the piston casting? Small camera trough oil drain hole or trough spark plug hole to check the dome? I think we have a tool to test the compression. Would this be enough also without piston casting? My heads are 14081054 and block 3999290.
Not far away from here is a machine shop, that does good work but it's very expensive in Switzerland so that's way I'm thinking about new heads.
Also the heads are fresh rebuilt so i prefer not to work on them.
But I have a stock 396 engine in my garage. It isn't assembled yet. (There was oil in the coolant, don't know why..) Those heads are 3964290 from a 396/402 with 100.9cc combustion chamber closed.
The engine should run with pump gas 95 or 98 octane or if there's no other way 100 octane. I don't want to rev it up to 6500rpm. I think 5800 is enough. I've never turned it over 4700rpm. If you need more details let me know, I will try to find it out.

And now the next question.. I have a 140gph 12psi Mallory fuel pump and don't know how to install it. My carb needs only 6.5psi so can I use a pressure regulator without return line or will this damage my pump? My father has a Sunbeam Tiger and when you switch the ignition on you can hear the pump but when there's enough pressure the pump switches of. How should I install my pump? I prefer the electric one because when I don't use the car for some time, it takes long time until the carb has fuel in it and the engine starts.

So thank you again and also thank you for your patience!
I like to work on my own car and i want to learn it.


The story how I get my Camaro
My father had a 69 corvette stingray for over 20 years and I worked a lot wit him on his car. So that's why I like the classic american cars. But unfortunately he sold the Corvette and bought the Sunbeam Tiger. I loved the corvette so much.. He also have a Ford A speedster 4 cylinder 1928 and a Morris Minor traveler. British car with small engine
So in january 2012 we went to San Francisco (first time in the usa but definitely not the last time) and looked around for a car. I preferred a Mustang Fastback or a Camaro. We found a nice camaro without rust and shipped it to Switzerland.
And now I'm happy with my car and like to ride and work on it. And for future my goal is a sleeper 57 bel air My first American car was a 97 Mustang Cobra.

Anyway here are the promised pictures
Club Hot Rod Garage

Tim

What's the casting number off the heads?

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Casting of heads is 14081054. Haven't found any info about this head. Some say 110cc combustion chhamber and some say 119cc..
and I also have 3964290 from 1970. Those should be closed chamber with 100.9cc but I also read that this head should have 109cc closed chamber..

Thank you

So how could i check the piston casting? Small camera trough oil drain hole or trough spark plug hole to check the dome?
Probably no way to tell what the pistons are without measuring them outside the motor.

I think we have a tool to test the compression. Would this be enough also without piston casting?
This will tell you only the cranking compression of the motor. You cannot tell the static compression ratio with this tool because the cranking compression is dependent on the intake closing point of the camshaft. Later closing lowers cranking compression and dynamic compression ratio. Earlier closing raises cranking compression and dynamic compression ratio.

And now the next question.. I have a 140gph 12psi Mallory fuel pump and don't know how to install it.
http://www.jegs.com/InstallationInst...0/650-4110.pdf
The most important thing about mounting an electric fuel pump is preventing it from transferring the drone sound of the pump into the passenger cabin of the vehicle. That sound might be OK for 10 minutes or so, but after that, it will make you not want to drive the vehicle any more. What you want to do is to completely isolate the pump from the vehicle with rubber. I used to use those chunks of rubber that look like they were sawed from an offroad tire, with the white cottom threads in them. They were used to hang exhaust tubing and mufflers, but they work great to isolate the sound of a pump.
http://image.classictrucks.com/f/tec...er-hangers.jpg
Further, a short piece of non-metallic fuel line should be used on the inlet and outlet ports of the pump, again, to prevent droning in the lines. A length of 5-6 cm should do the trick. Again, no part of the pump should be in contact with any metal part of the car.

My carb needs only 6.5psi so can I use a pressure regulator without return line or will this damage my pump? My father has a Sunbeam Tiger and when you switch the ignition on you can hear the pump but when there's enough pressure the pump switches of.
No modern carburetor needs more than 5 psi at the fuel inlet of the carb and most of them will work better at a little less pressure, like 4 3/4 psi. More pressure than that can over-power the needle and seat in the bowl and allow the pump to blow raw fuel into the intake manifold, creating a tuning nightmare for you.
Using a return line will allow the pump to live a longer, happier life and will also lower fuel temperature. A system without a return line is called a "deadhead" system and is not recommended. What you are describing about the pump shutting off, it never really shuts off, it just goes into a rest mode when the pressure in the line reaches the max output of the pump.

Casting of heads is 14081054. Haven't found any info about this head. Some say 110cc combustion chhamber and some say 119cc..
and I also have 3964290 from 1970. Those should be closed chamber with 100.9cc but I also read that this head should have 109cc closed chamber..
14081054 is the part number for a Chevy valve. The casting number off a 396 or 402 cylinder head will likely begin with 3 and be 6 or 7 numbers long.
Here are some numbers I found on Mortec....I included heads from the 366 tall deck truck motor because their bore was 3.935", so these heads could be used on a 396 or a 402.
330864.....68-84...oval...OPEN...396, 402
330865.....68-84...oval...OPEN...396, 402
343771.....68-86...oval...OPEN...366T
343772.....68-86...oval...OPEN...366T
473328.....68-69...oval...OPEN...366T
3856206....65-66...oval..CLOSED..396, 97cc chamber
3856208....65......rect..CLOSED..396/425hp, 109cc chamber, 396/375 hp "Z-16" Chevelle
3856213....66-82...oval..CLOSED..366T, 427T
3856260....68......oval..CLOSED..396 Truck
3872702....65-66...oval..CLOSED..396, 427, 98cc chamber
3873858....65-67...rect..CLOSED..396, 427, 109cc chamber
3904390....67......oval..CLOSED..396, 427, 98cc chamber
3904391....67......rect..CLOSED..396, 427, 107cc chamber
3904393....68-76...oval...OPEN...366T
3909802....67......oval..CLOSED..396, 427, 101cc chamber
3917215....67-68...oval..CLOSED..396, 427, 101cc chamber
3917219....68-85...oval...OPEN...366T, 427T
3919840....67-69...rect..CLOSED..396, 427, 107cc chamber
3919842....68-69...rect..CLOSED..396, 427, Aluminum L88, L89, 107cc chamber
3931063....68-69...oval..CLOSED..396, 402, 427, 101cc chamber
3933148....69-84...oval...OPEN...'69 396/265hp, 366T, 427T, 112cc chamber
3964290....69-70...oval..CLOSED..396, 402, 427, 454, 101cc chamber, large or small hex spark plugs used
3964291....69-72...rect..CLOSED..396, 402, 427, 454, 109cc chamber, Large or small hex spark plugs used, crate motor usage in years after 1970.
3965198....68-69...oval..CLOSED..396 Truck
3975950....68-70...oval...OPEN...396, 402 Truck, 366T, 427T
3986133....68-85...oval...OPEN...366T, 427T, 454 Truck
3986135....69-73...oval...OPEN...366T, 427T
3986136....68-84...oval...OPEN...366T, 427T, 454 Truck
3993820....71......oval...OPEN...402, 113cc chamber, 255/114 ports
3999241....72......oval...OPEN...402, 454, 113cc chamber
6272292....70-78...oval...OPEN...402, 454
14081052...85-87...oval...OPEN...366T, 427T, 454 Truck, Marked "HiPerf"
14092359...86-90...oval...OPEN...366T


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Tech, you're the best!

366 and 427-454 heads all fit on the 396/402 bore and many of the rec port hi per gm heads were used on the 396 hi out put engines that came with 2.19 intake valves bigger valves up to 2.250/2.300 intake can fit with a clean up on the stock relief i done many 396/402 over the year with 2.19/188 valves that never came in any O port head in iron but was a stander size valve on the gm hi hp engine that was use on all Gm build up but the 366and 427 tall decks engines .most all 396 were 325hp /350 for latter on both used cast pistons why gm used smaller chambers then moved up on bigger chamber heads was to cut back on the CR of engine fule and some say for better burn clean air act ? smog 402 still had dome piston and many used the a 110 to 112 real world cc casting 291 heads used on many 454 as well there about four casting numbers on this head from gm.i used them all.. as it seen use in the tall decks truck engines and car 402and 454s . engine is small in size so very few oval were to small or bad to feed a street 396 as for domes there really no need to check for domes all cast piston and forged pistons all came with domes many forged were oem copy of the 325hp piston all the 396 two barrel engines had the small domes that were angle cut much like a diamond trw speed pro made many forged piston for the 396 that are not made any more companys like Icon pistons and wiseco/je make some bigger domes and there is custom pistons as well from any good companys that build pistons so you need the stamping number on piston top to tell you what you have if there a flat top pistons in that engine the only way that happen is some one cut the domes off if that happen yes it would run very poor

Thank you Pat & Techinstructor!

Now I know how to install my fuel pump I will buy a return style regulator.

But I don't understand exactly how to check my piston casting? Is it on the top or bottom?

I checked again my head casting. It's 14081052 not 54 in the end. It's the oval open truck head. Have those heads hardened seats and are good to go with unleaded fuel?
Anyone know the cc volume? I think between 112 and 119cc but not sure.

I think to bring the heads to a machine shop is to expensive, so I would prefer new aluminium heads for the same price. Those aftermarket heads I knwo would have 110cc combustion chamber.

Would it be an option to put the 396290 heads with 101cc combustion chamber without modification on the engine instead of the 14081052 with the bigger combustion chamber (between 112-119, don't know exactly) Higher cr=more power?

To know if there will be an interference (valves vs piston)you need to know which pistons I have right?

Today I installed my new Recaro specialist seats. They don't look too modern and fited well in the car. Now I have a headrest, 4 point seat belts and don't anymore slide off the seat in curves

Do you already cheched ou my photos of the car? On my profile in the garage.

Thank you
Tim

Tim checked your garage and want to warn you that lifting a BBC like that with chain links against the valve covers will end up denting or warping the covers-
Use bolt holes on front and back of heads so chain doesn't touch valve cover or preferred get an carb plate lift plate that bots to intake manifold-


Glad to have you here altho the site seems to be getting pretty slow--------

You said the pistons are stock and the motor was rebuilt 1,000 miles ago. Is there any paperwork that would identify the piston part numbers?
If you're going to get back into the motor, pull the heads and see if there is any I.D. on the piston crowns. While you're there, bring #1, #2, #7 and #8 pistons to top dead center and use a straightedge and feeler gauges to find the piston deck height (the measurement of how far down in the bore the piston crown is with the piston at top dead center). It will also give you an indication of whether the block was milled squarely at the factory. When the block is square, the heads will sit squarely on the block and the intake manifold will sit squarely on the heads. Also use your dial caliper to measure the compressed thickness of the head gaskets you remove. Don't have a dial caliper? Get a good used Mitutoyo, Starrett or Brown & Sharpe off ebay. A 12" dial caliper will allow you to do any measuring on the motor, including block deck height. Here, a block is being measured for block deck height using an electronic caliper. You would add the radius of the main bearing bore to the measurement found using the caliper.
http://www.jamisonequipment.com/picPage/BHM-24-1.gif

I have owned electronic calipers, but every time I would reach for them, the batteries were dead. Dial calipers are bulletproof.

I would get a good cc kit so I could measure the cylinder head chamber volumes. Here's an example:
http://www.summitracing.com/parts/cc...GJkaAp0B8P8HAQ

Take a photo of the piston crowns and post for us to see.

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