what can i do to give my 305 more hp? my money is low.i took egr off. I have a iroc z28. I need help?

 

head upgrade
headers
intake
exhaust
cam swap
roller rockers
carb or injection upgrade
ignition upgrade

 

You got it all there

A little order could be helful. If it were me I would go like this:

1. Exhaust. All of it. Headers to tips.
2. Heads
3. Cam
4. Intake (if TPI, anything but TPI )
5. Carb If necessary

Of course, many people change heads and cam at the same time. As general said about roller rockers, these usually come when someone changes the cam. Have fun with it.

 

But if it were us we would well you know just throw a 350 in it and be done....LMAO

 

Well since you said that money is low....

if you have TBI or a Carb, then a open element will help you breath a little. How tight you are on money depends from there. Deleting EGR wont really gain you any ponies.

Just a full exhaust will wake up the monster that is 5.0l (look, i made a funny mawh).

Get a 3 inch catback, high-flow 3 inch in/out catalytic converter, and headers (hooker is the best bang for your buck even if you have to save for a little bit).

If it's not your daily driver, then you can take the heads off and port and polish them yourself (search up "Sitting Bull" he has made an extensive article on how to home port, for under 150 dollars in tools). And then while you're at it you can port your intake to match.

If you have a carb, and it's stock it's probably the computer controlled Q-jet. That carb is good to about 300hp, so you wont have to upgrade it. But rebuilding it, and then changing the rod and hangers to your selection should help that too.

I dont know how much a ignition upgrade will help you, since you have HEI, but The General said it, and he knows way more than I do.

If you home port your heads, then you should put in a new valvetrain, the Comp XE268H (I think that's it atleast? probably wrong) has a powerband of like 1500-5600, which is a great improvement from the stocker.

This all will cost you a good chunk of change, but not so much as if you were to go out and buy new heads, new intake, have a "professional" mechanic do it.

I'd do it in the above order as well if I were you.

 

he wont need the ignition upgraded until he gets all the other parts installed such as cam , headers, exhaust, intake, carb or injection upgraded. ...and so on the ignition will be one of the last ones on the list i just spit them out as they popped into my head....but lj sorted thru them and put them in order...#6 would be the ignition...

 

Ported "416" heads (factory LG4 heads)
Comp Cams Xe256h
ZZ4 intake
Edelbrock Performer carb, 600 cfm
Mallory HEI
Factory exhaust, but I don't really care

This used to be my LG4 in my Caprice. Then winter came and I wanted the benifits of the Q-jet back. It was a decent combo. Sure, it could have benefited from an exhaust, but it wasn't meant to be a performance issue. It was a happy engine. The cam works well with factory compression and the lift abides by the factory bounds. The cams powerband fit nicely with the factory converter and the lame rear. Overall a decent engine.

 

Sounds like a nice, user friendly 305.

 

When you start making mods that push the power band above 5K is when you should start thinking about ignition upgrades, IMO. A good coil is always a good thing, but the stocker will do it. I have had engines that spin to 7k running off of stock HEI setup. All the way down to the module and coil. After around 7k the stock stuff starts to have a diminishing effectiveness. A good addition is simply a 50K volt coil, good module, cap with brass inserts and a nice set of wires. That will give all the spark that a good street engine really needs. I like the MSD 6AL, but it really isnt needed at all on a build of this caliber.

 

It was extremely nice, I loved it. And it was a very very budget friendly build.


thomas_iroc, here is my suggestion to you.

Start with the exhaust. Lots of options here. I'll let you discover what's best for you.

Go to a junkyard and ask if they have a set of cylinder heads for an 85 Caprice Classic, carbureted 305. (Any engine with a carb 305 will suffice as the head castings are essentially the same). you should snag them cheap. Look up a guy named Sitting Bull. He has a good thing in his sig about working them over. I put 1.94" intake valves in mine, left the exhaust alone. I ported them myself, its really easy. I left the valve guide bosses as they are and pinned the studs myself. The only thing spent on the heads is the price for the cores and machine work. Cleaning them up and machining for larger intake valves.

A ZZ4 intake can be found on eBay (that's where I got mine). It's a great intake. 50 state emissions legal and takes the Q-jet can be bolted up to it. I find it to be somewhat of a step up from the Edelbrock Performer series (I have both). You can omit this if you want.

Get the K-kit for the Xe256h. That's the cam, lifters, timing set, springs, retainers, locks, seals, and some assembly lube. Essentially everything you need and its all conveniently matched. It's like $350 for the entire kit.

Re-use your Q-jet and distributor. That's about as budget-friendly as it gets while still making positive progress as far as the power output of the engine is concerned. You can pretty much assemble everything yourself. Autozone rents all the specialty tools ans what not. You don't even have to pull the engine or even raise it. This is ESSENTIALLY what I did, except I put on my Edelbrock carb and Mallory HEI from my Camaro while I was going to rebuild the Q-jet (never got around to actually doing it, though )