Hey guys, Just building a new 308 motor and not quite sure what to expect out of it and was wondering if anyone might have an idea of power or know of some similar combinations and what power they have made. any help would be appreciated. -308 Standard Stroke -Decked block and heads, flat tops, comp ratio of just under 10.5 to 1 -Ported HQ pre pollution heads. Standard valve sizes. Yella terra rollers. 57CC. -Custom grind Crow solid with .550 lift. Double valve springs etc -Edelbrock Performer Manifold -Holley or demon 650 or 750 double pumper. Any thoughts or advice on the build would be great.

hey mate, well just for a guide, when my 308 got built, i was told to see around the 380-85 hp mark. thats an injected block, flat tops, think 9.2 comp or near, shotpeened rods, balanced crank, ported yella terra heads, crane 286 cam, 650 holley mech secondaries, performer dual plan manifold.. but my dads mate who pretty much use to just build high performance 308's told me with the same combo and a few secrets, youll see easy 420 with the same parts.. but i didnt want anything radicle, just more reliable.. hopefully thatll give you a rough guide, but you will definetly make more hp then mine whats she going into and what box? Some original photos have not been recovered yet.

Id imagine you'd be around the 380hp mark somewhere, I dont think it would be much higher.

Ahh cool thanks for the tips huys. Yeah high 300's sounds pretty good for a 308. Hopefully it goes ok in the car. Cheers ---------- Post added 29-06-10 at 22:34 ---------- Also guys I am till yet to buy a carb for it. I have been told a 750 might be a little big. What do you guys think? and also the power/value for money between a holley and a demon, is there any??

Sorry PSIEFI I forgot to add its for a HX GTS Monaro with a 4sp manual. Some original photos have not been recovered yet.

go an auto in it

I would love too hijakt but money is the big killer in all car builds, just cant afford it at the moment

i couldn't see the aussie 4 speed lasting too long behind a decent 308 unless you take it real easy on the gear changes and no dropping the clutch etc...

I reckon you would get to the magic 400hp easy.

i wouldnt use standard hq size valves go for the l34 type vn size, depending on the port job, you should clear 400 at the fly ive built similar type engines and cleared 400hp with a dice special solid camshaft lol...but lots of hours on the ports.

Thanks 4 your thoughts guys! It would be unreal if it cracked the 400hp mark. I know an auto or a tougher manual is definately needed, but it all adds up doesnt it, I will definately do something about it when the spare cash comes up. An update on the motor though, I've put together the bottom end and I'm just waiting on getting the heads back from the shop, they are getting surfaced and machined for some decent double valve springs. After I get em back i will get stuck into fitting the cam and the heads etc. I think I will get stuck after that for a little while, while I wait for a good second hand carby and manifold to come up. I think what i will end up chasing is a demon or holley 750 dp and im giving some serious thought to a torque power or similar high rise manifold. Anyone have any ideas on what times a 400hp motor would get a full street hx down the quarter in? Im thinking about having a crack when the motor is done. Keep up the comments and ideas guys cheers. ---------- Post added 15-07-10 at 02:19 ---------- Also Dice Auto, when I bought the heads I hunted around for ages for a set of big valve heads and everything that was for sale at the time was crap. The heads I bought were ported and cleaned up a little, machined for screw in studs, and i bought the roller rockers of the same bloke and got a very good deal. Now sure enough I look around and there are a few sets of cheap L34 heads, but for now I'll make do with what ive got Some original photos have not been recovered yet.