help! with my stock 280z

[3RD STRIKE]

Well maybe i jumped the gun at your staement, but I did not make any false statements about the stuff that i have mentioned in my previous posts. I have tried it and proved it to be true. I spent whole summer making adjustments each week then going to the track to see what made me faster & lighter. Everthing that i have changed on my Z has made an imporvement as far lightning the car and/or adding horsepower. Your right everything on here is available for research (which everyone SHOULD do). Adding horsepower isn't the ONLY thing that is going to make your car quick. Making the car lighter, knowing how to drive the car, and knowing what the car is capable of are all very important. You can add all the bolt on's you want but if you don't know how to drive the car, they are really not going to make a difference. In short, I guess everyone has to figure out what's right for them and their car, this is what was right for mine. oh yeah by the way, dont use a turbo clutch, on a non-turbo car, it really sucks.

[ecp48]

The only exception to the "easy bolt on horsepower" is the late 280Z. The 78 has a very restricted two into one pipe. They are so short and tight, the tubing is rectangular. Replacement with a header will free up the bottle neck. Pace Setter or MSA will work. MSA had the thicker flange (better mount), the last time I checked. The 78 280 should have the N47 round port head. I say should, because my 78 had a rebuilt Lazorlite installed with the N42 head and I have additional restriction with a round port manifold on the square port head. Look at the side of the head for the N47 marking. If so, then you need the later round port header. You might want to check ebay.

[3RD STRIKE]

Hey, Ive got a question. I have the n 47 head. My question is if you do port work on this head, can you take the heat shields out? Also does it make any difference? This head is an 80 man. date as far as i know. If i can take these out, is there any damage risk?

[TomoHawk]

Before you try to "bolt on" horsepower, you need to make sure the car is working its best with the parts you have. Make sure the air/fuel mix is right, the spark plugs are good & timing is at its best, your trans isn't slipping, and all the rest of the stuff. If the clutch was old & slipping, a new one may have been in order but changing the cluch to a 'performance' unit may have been just wasting money, as just a new tock unit could have done the same.

An entire engine rebuild, on a car that could be up to almost 40 years old, may even be in order...

Replacing the stock fan didn't necessarily need to be done, as the fan shouldn't be totally engaged if the engine is cold. That bit was a 'luxury.'

Saving weight is only good as long as you save a LOT of weight; the rule of thumb is that for every 100 Lbs. of weight removed will save you 1/10 second in the 1/4.

Putting go-fast parts on a poor engine or car just makes it a more expensive slug.

[ecp48]

Taking the heat shields out leaves a big, irregular opening, worse flow. If you check the many threads on this topic, here and at Hybrid Z, you will note that the N47 flows very well in stock form. Just clean up the valve bowls or pockets.

[sblake01]

Putting go-fast parts on a poor engine or car just makes it a more expensive slug.

Not to mention that it will also shorten what's left of it's life. I've been trying to impress that on my son for a couple of years now. Wait a minute, did TomoHawk and I just agree on something?:classic: