hi all,

i have a 570cfm holey and a weiand 8124 intake waiting to go in (whenever i'm bored).
I thought as well about upgrading the cam to a compcams 256HE, but thought it might be an idea to upgrade my heads first. I can't afford head _and_ cam.
Gettign a GT40 and porting it is not an option as I have to go aluminum (shipping costs from the states) 100lbs vs 50lbs
the engine is a stock 289 from 66 with headers and proper mufflers.
I saw that JMD is selling heads, but I believe the proforms with 2.02 valves will not fit without cutting piston, which is not an option either.

So what's left is:
performer rpm with 1.9 valves http://store.summitracing.com/partde...5&autoview=sku

twisted wedge http://www.trickflow.com/partdetail....2&autoview=sku

AFR is a bit expensive, so can't go for them.
I don't want much more than 300HP/TQ finally as i don't want to blow my T5.

any other recommendations ?

at the same time they all seem stud mounted and my stocks are probably pedestal. Is there anything I'll need to change apart from the rockers and the pushrods?

thanks a million for any ideas/recoomendation

P.S: I'm actually looking for used ones so that it can be declared as used part @customs (way cheaper)

 

Kalli,

I want to ask you a newbie question. (I know a lot about things that I have already done to my car, but nearly nothing about the parts I havent needed to work on.)

Do better heads simply create higher compression (more dense oxygen, thus more efficient explosions)? If this is the case, do you have to rebuild an engine to have "better" rings to handle this increased pressure?

If the Edelbrock is simply a bolt on 50 HP jump, wow. I will be all over that. I was under the impression that rings had to be changed too.

Thanks for dealing with the newbie-ness.

 

secret for HP is airflow. means carb, intake, heads, exhaust system
if one of them is restricted the HP ratings will go down.
the stock heads flow **** (as in very very bad), so aftermarket heads will therefore increase HP. some more, some less.
How much depends on the rest of your engine and system. lets say you have a 300cfm carb with stock intake and exhaust you might gain 20HP with a set of those, the increase will be much higher when you have better flowing components in those places (as much as 50+HP)... camshaft plays an important part here and needs to be matched with rest of engine

that's the theory. What I'm trying to figure out is will the ones i posted run without problems on a 66 289 and what other parts (rockers ... I'll need)

as for compression ratio. the higher the ratio, the better. But from a specific ratio you cannot run pump gas anymore. I'd say a good compression ratio for a 289 would be 9.5:1
some1 correct me if I'm wrong here.

 

In your case, Kalli, I think the Twisted Wedge heads would be perfect. They don't require flycutting your pistons, even for higher lift cams than what you're looking at, and they flow great under .500" lift.

Your original rockers are stud mounted, so you don't absolutely need rockers, but a new set is a good idea. If you're on a budget, Comp Cams Magnum roller-tip rockers are a good product at a decent price. Crane also sells their Energizer full roller rockers for cheap.

 

Hi Tad,

thanks a million for info. I was eyeballing those twisted wedge ones alright.
for some weird reason i always thought they were pedestal. never really knew the difference.
Sheds new light on the thing.
I'm thinking about new rockers alright and maybe hardened pushrods. no idea if I'll need them. would you get them straight away or would you get them at a later stage with the cam?

kalli

 

I'd get them now, if you can afford it. You'll absolutely need new pushrods as the Twisted Wedge heads use drastically different length pushrods than normal heads, and the rockers are just good to have. You'll be able to keep both if/when you swap cams.

 

great! I'll contact trick flow to see what size I'll need (i hope they know)
i want to be on the safe side and therefore get new rockers. I can't afford roller tip rockers, but will get them anyway .... arghh my wallet will hate me

 

but your car will love you :P

 

i think i have to run this through my girlfriend ... :-]

 

WTF? Are you kidding me?