Hot Rod Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
Hello!


I'm looking for camshaft suggestions.
What im about to build is a Pontiac 400 with a .040 overbore, +17cc dish pistons, ported #13 heads (72cc), Edelbrock Performer RPM intake, holley 750cfm with vacuum secondaries.


If my calculations are right that should give me about 9.30:1 compression ratio depending on wether or not i'll have to deck the block.
My aim is street perfomance but i'd still like to be able to cruise.
...But mostly for pissing off my neighbours.


Greeting from Sweden and please excuse my Spelling.
 

·
Registered
Joined
·
207 Posts
I'm going to take a different tack. I've used two of the XE cam grinds, and while they have their place, I really don't like them for a real performance build. They have a LOT of valvetrain noise and they are hard on parts. Yes, I had them set up properly but I still killed the needles in 2 sets of roller rockers with a XE274.

I'd suggest a Crower HFT in the 220-230 degree range with a 112LSA, depending on car and gearing. Nowadays a hyd roller is the way to go for a max effort street engine, but they are expensive.
 

·
Administrator
Joined
·
8,252 Posts
Hello!


I'm looking for camshaft suggestions.
What im about to build is a Pontiac 400 with a .040 overbore, +17cc dish pistons, ported #13 heads (72cc), Edelbrock Performer RPM intake, holley 750cfm with vacuum secondaries.


If my calculations are right that should give me about 9.30:1 compression ratio depending on wether or not i'll have to deck the block.
My aim is street perfomance but i'd still like to be able to cruise.
...But mostly for pissing off my neighbours.


Greeting from Sweden and please excuse my Spelling.



What Octane is available? What will you be willing to run?


How heavy is the car?
What gear ratio is the rear?
Which transmission you running , manual or automatic?
What is cars intended purpose, race , street, or a combo of both?


All these questions need answers to even get close to a good recommendation for a cam.


Your octane in Sweden may be higher (IIRC it is) than anything in the states. Meaning, you can run a higher CR, and a hotter cam.


You wouldn't run a cam with 230 duration @ .050 in a engine with a static CR of 8.5 or less in a 4200 lb car with a stock converter and a 2.88 gear. It would be low on takeoff power. That kind of cam size needs at least 9.5 to 1 to work well


Feed some more information about your build and we can help you "tweek" it so you get happy when mashing the pedal on the right.
Latech


P.S. I calculate your static at 9.0 to 1
 

·
Registered
56 chev on 79 chassis, 62 LeSabre
Joined
·
3,126 Posts
i'm with you, LA, or a little less, depends on how far down the hole he is., i'm at 9.1 and i have i believe 14cc dish with the 8 brow pistons i got and 74cc 061 heads. you and others have recommended the 068 cam and i can't see him doing any better than that. and thanks alot for that advice btw LA. you recommended the o68 because of my detonation prone 8 brows, maybe if he has better slugs you could steer him to a more modern version of same. btw i am 30 to 40 down the hole, it varies, so i averaged them at .035 down. if i remember right i'm just a RCH below 9 but oh so close.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #7 ·
What Octane is available? What will you be willing to run?


How heavy is the car?
What gear ratio is the rear?
Which transmission you running , manual or automatic?
What is cars intended purpose, race , street, or a combo of both?


All these questions need answers to even get close to a good recommendation for a cam.


Your octane in Sweden may be higher (IIRC it is) than anything in the states. Meaning, you can run a higher CR, and a hotter cam.


You wouldn't run a cam with 230 duration @ .050 in a engine with a static CR of 8.5 or less in a 4200 lb car with a stock converter and a 2.88 gear. It would be low on takeoff power. That kind of cam size needs at least 9.5 to 1 to work well


Feed some more information about your build and we can help you "tweek" it so you get happy when mashing the pedal on the right.
Latech


P.S. I calculate your static at 9.0 to 1
Well the pumpgas available in Sweden is 95 & 98 but that is RON, so 98 would give me 90,5 PON which i guess is octane rating in the US.

The rear is stock right now so it should be 2.41.

Transmission is THM350
weight is about 4000 pounds according to the registrations papers.

The intention with the car is to make pony driver soil them self by the stop lights. Im not a restoration guy, i wanna go fast and feel the torque push me forward. Purely a toy.

I guess the rear axle is going to be swapped at some time for a 12-bolt chevy and the transmission is probably gonna blow up in my *** sooner or later but I'd really like to start with the engine first and do it right. Cost for arp bolt and gaskets in Sweden are probably 4 x the price in the US.

Thx for all the replies so far!
 

·
Registered
Joined
·
5,072 Posts
The big thing I would do is junk the factory connecting rods. They're well documented for blowing up when you go pony hunting.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #9 ·
The big thing I would do is junk the factory connecting rods. They're well documented for blowing up when you go pony hunting.


I'm planing to use some 4043 forged H beam rods. The engine is still pretty much stock at this moment other then intake and carb. I've got the #13 heads on the shelf and am about to dissassemble the engine and send it to a machine shop for the .040 bore.


Skickat från min iPhone med Tapatalk
 

·
Registered
Joined
·
17,613 Posts
Howards hydraulic flat tappet cam and lifter set, part number MC410021-12, 5-year no-fault warranty.
Advertised duration 267/277
0.050" duration 213/223
Hydraulic Intensity 54, for good solid valve action, max power with valvetrain longevity and quiet operation.
Valve lift 0.450"/0.450"
Intake centerline 108
Exhaust centerline 116
Lobe separation angle 112
Intake opens (-1.5) BTDC, Intake closes 34.5 ABDC, Exhaust opens 47.5 BBDC, Exhaust closes (-4.5) ATDC
Operating range 1500-5800
Super low and midrange torque, excellent drivability.

Machine the heads for Howards 98412 valve springs, but use old, worn-out springs for the cam break-in, then change to the Howards springs.

Follow this tutorial closely to make the flat tappet cam work in today's roller tappet world.....
http://www.crankshaftcoalition.com/wiki/Camshaft_install_tips_and_tricks

Talk to me on PM if you'd like to make a deal where I buy the cam, lifters and springs and ship them to you as a commercial sample....

.
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #12 ·
Can't PM due to forum restrictions, I don't have 20 posts :(
My mail adress is the same as my forum name with @gmail.com in the end.
 

·
Registered
Joined
·
686 Posts
I would spend the coin and go hyd roller. Your much better off especially since you are over the pond.

Eddy heads like a reverse split camshaft, more duration on the intake then exhaust. These engines make a ton of torque. Last one I cammed was 490HP and 580#/ft on pump gas 89 octane.
 
1 - 14 of 14 Posts
Top