Hey guys,
i got an 1983 Z-28, was standing the last 10 years.
So know I wanna get him some life back.
I think i had to overhaul the engine, 'cause the smoke it blows out when i start isn't any more funny :-), the neighbors and me, well, we could be better friends *hehe
So i think, the heads i head to take off. I hope i can let the engine in, 'cause I'm not that good equipet in my garage.
So how do I get more torque/hp, without spendin' a lot of money.
I know how to make a car faster, but i wanna know what has a big effect and does not eat all my money.
My plans are, to have an engine, which gets my 'maro good in motion. No drag racer, but able to smoke some tires. About 250+ hp. Primary torque, not an engine which turns 'til 8000 R/pm
So I hope you got some good ideas for me,
Thanks
Hawk

 

I doubt that the motor needs a rebuild, the valve seals are just leaking or missing which causes your startup smoke. If the engine turns out to be bad, which it is not, replace it with a 350. Never rebuild a 305 it is not worth the money and in many cases costs more to rebuild, than a 350.

As for more power a 350 will help alot. You can do a on here to find out some really good info.

 

Torque and 8000 RPMs don't belong in the same sentence.

Of course, neither do lots of horsepower and not much money.

250 HP can be had at 5500 RPMs. Depending upon which engine is actually in your car, you're probably looking at all new exhaust, different cam, and some work on the heads. I'd say, "Get a 350", but your resources may be a little limited on that side of the pond. Unless you get something off of an American military member, that is.

 

For sure 350 is the best solution.
But.
I just wanna drive 1-2 years with the car, just a fun car for the summer, you know.
So I'm not plannin' to put alot of time in it.
And have you ever tried to get a good 350 over here?
Most times, they are standing in garages for years. No one knows if the are runnin', how much miles they got an so one.
Or the want a lot of $ for a engine. And i don't want to spend 1000€ just to have the engine.....
So I thought, maybe there is a cheap way to get 250 hp out of my 4 bolt.....
How much more would I get by usin a new cam, bigger carburetor, different manifold and maybe better heads....
What about changing translation of the rear axle to get better acceleration???
Thanx
Hawk

 

What engine do you have now? 3rd gens didn't come with 4-bolt main blocks (although you never know what they exported).

You probably don't need a different carb. The one on there is capable of pretty good power. The heads can be ported/cleaned up and will work fine with new valve springs.

Changing the rear axle ratio might get you going quicker from a stop, but you'll sacrifice autobahn cruising speed to get it. Do you know what it's got now?

 

 

I've looked here >
LG4
Ohv V8
145 @ 4000
240 @ 2000
4-bbl.
8.6:1
305/5.0
Z*,SC,B

LU5
Ohv V8
165 @ 4200
240 @ 2400
TBI (CFI)
9.5:1
305/5.0
Z

I do not have a TBI, so....oh wait. The 4 bbl, is for the carb, right?
Ok, I do not have the block no. right here. All I know it's a 305, with carb.

For sure, high speed isn't possible, when puttin' setup on 1/4 mile. I'm planning to drive it most times in town, blowin' some some VW's and BMW's ;-). Top speed isn't my motivation.

 

If its a 4-bolt the chances of it being a 305 are almost nill. Only a select few canadian truck 305 got 4-bolts, but i don't know about export. Find the casting numbers of the block and the heads, then go to www.mortec.com

250 hp is not hard to get, your a cam, intake, carb, header, and exhaust swap away. You may not even have to port the heads. But if your getting them rebuilt, do it anyway.

But find out what you have before you start planning anything.

 

Nothing wrong with the carb on there now with respect to achieving 250 HP. I'm doing that at the rear wheels.

 

OK, if it were mine, and I wanted to increase power on the cheap, (you might not get 250, but it'll get you most of the way there)

1) pull the heads, valve job, new seals, pocket port and mill the snot out of them for more compression
2) Headers if you can afford them, larger exhaust piping and a free flowing muffler. I don't know German smog laws, but Pitch the catalytic converter if you can. If you can't, a free flowing model will do fine (bye bye to more Euros...)
3) 1.6:1 ratio rocker arms (in place of the 1.5:1s' to give you more valve lift) Ideally, swap to a High Performance cam and lifters, but that might be expensive to get in Deutschland and is a complicated job if you don't have good tools. If you do a cam, change the timing set, too. A decent cam will make a huge difference in performance.
3) free flowing air cleaner, and you will almost certainly need to jet the carb up a few sizes. you should be able to find Quadrajet jets even over there, but if not, they are tiny and will not kill you to get them shipped.

Good luck! Auf Weidersehen (sp?)
Troy
So Cal

 

Actually you are correct, i was just thinking get rid of the computer controlled stuff. But really you might be able to get 250hp with it, i don't know never tried with a carb computer.

 

OK,
just tried to find the block numbers. Not really a success. Too much stuff in front.
So for our considerations, it's a 305 2 Bolt.
I do a short summary, to be sure I get it right.
Carb: standard
Heads: standard, but reworked...
Cam: Aftermarket
Rockers: 1.6 instead of 1.5
Lifters: Aftermarket (maybe)
Exhaust: Bigger pipes, catalytic converter.....I got none :-). This point I had to do later, 'cause the car needs a new permission, so it's easier to achive this, with original parts....a lot of laws over here.
Air filter: K&N or stuff like that
Exhaust mani: headers
What about intake manifold???

 

Decode your vin #, If you have the L69 engine just replace the cam and lifters, add headers and 3-inch exhaust and port your heads. If you have the LG4 replace the intake manifold as well. For the cam, if your just wanting a lot of off idle torque I would get the comp cam xe256. If you want to be a little faster get the xe262.

 

So here's my current "virtual" setup.
cam> Comp Cams XE256H
intake> Edelbrock Performer EPS (idle 5500) #2701
lifters/rockers> Comp cams 1.6 Mag Rockers & HE Pushrod KIT
heads ported
filter> K&N
carb> standard
headers and exhaust later.
Is this a setup, where I can "work" with? I mean MORE POWER...
How much do I get? approximately.
What about the "followin'" parts. crank, rods, gearbox, rear axle etc... Can they handle that?
What about usin' a smaller head gasket?

 

Except in Canada, LG4 and L69 both had the same manifold.

If Hawk's carb is computer controlled, most likely he has an aluminum intake as well.

I haven't heard much about the EPS vs. the older Performer, but unless it is a signficant step up from the older Performer, it isn't much better than stock. But, probably not a bad choice. Consider the Weiand Action +, though.

I'd use a thin steel shim head gasket - make that, I did use a thin steel shim head gasket. The rest can handle the power you'll make just fine. You should see 250 HP with the right cam.

 

This is very similar to what I have in my Caprice (LG4).

I worked over a set of 416's. Increased to 1.94" intake.
ZZ4 intake (another highly suggested intake)
Xe256h cam
Magnum 1.6 rockers
Granted it blows through the factory exhaust with a poorly geared peg leg rear, but it gets me around.

 

Just looked at the hp from Weiand.
There are 3 Action +, only difference in my eyes is the size.
But another intake looks good, what about Weiand Team G? I've heard it's a very good one.
But why they are offered in differnet sizes? Is it just when you do not have enough space that you take a smaller one?
Or how should I choose them?

So 250hp should be possible or what?

VIN > I got a LG4, by the way.