How much power is enough in a Z?

[Guest butlersZ]

I'm in the middle of a scarab style conversion in a '78 280, I have a motor built for it and installed for mock up and now I'm going to pull it back out for bodywork and paint all while, Not knowing what type of hybrid I really wanted.

 

Well know I know and I want to build a car not so much for the quarter mile but for the road, I want exceptional handling while at speed like on a road race course or a rally on tarmac. But I still want to be able to smoke those pesky front wheel drive piss-buckets and 5.0 ponies. Gas mileage would be nice at 20MPG but I guess I probably can't have my cake and eat it too.

 

Can anyone tell me how much power they think is sufficient for a Z to go road racing and still have street manners? I'm guessing 400Hp/400Tq at the flywheel would be perfect, but I am seeking the knowledge of those who have been there and done that. And I am talking about a SBC powered Z. Could some of you guys chime in and tell me how much power they think is enough in a Z?

[BleachZee]

I have heard that even with an LSD, traction is very limited over 300tq. 300-350hp seems like it would be too much for the car where you have to hold back to keep from going sideways. I know everyone with a V8 has at least 300hp, but I'm suggesting that 300-350 is probably all you need.

[Tim240z]

enough!! It's NEVER enough. IT will be enough for a while, then you will want more, then more, then more.......it's a vicious circle!!

[deMideon]

I'm probably putting down about 400hp.. I do have an aluminum flywheel too, so that drops the low end torque a bit. I am also using a T-56 trans so I can feather the clutch as well. Anyway I am finding that the car is very easy to drive on the street, very very fast as well. I haven't quite gotten my launch figured out yet and I am at about 4.5 sec 0-60! I'll probably be around 4 seconds once I get better. Heh but it looks like I am getting about 12 miles per gallon!

[johnc]

ITS 240Zs do just fine road racing with 200hp. The issue is never the power (unless you're Shuie, Donahue, Gurney, Earnhart, etc.) and always the driver. There's only one V8 Z that I know of that can equal the ITS lap record at a race track.

 

But I still want to be able to smoke those pesky front wheel drive piss-buckets and 5.0 ponies.

 

Again, all you need is about 200hp to do the above regularly. With 300hp you should be able to beat Z06 Corvettes and Vipers regularly.

[Tony D]

wrong place to ask that question!

 

I have to agree with John: most people can't drive their STOCK 240 or whatever to 10/10ths before they start gobbing in more power.

 

More power makes you lazy as you think you can always "make up time" on the straightaways. Watch the old Corvette/Lotus battles of the early days of televised roadracing and you will see this laid out very well.

 

A balanced machine will ALWAYS be faster than one with just one good attribute. Building a car that you can never drive to it's fullest is both sad, and a sorry waaste of good resources.

[z-REX]

A balanced machine will ALWAYS be faster than one with just one good attribute. Building a car that you can never drive to it's fullest is both sad, and a sorry waaste of good resources.

 

great point tony! but while this is 100% true... there's nothing like a car that can make straight-line acceleration feel like warp-drive. but our cars are so much fun on a tight backroad that overbuilding the engine can really hurt the best quality of the car.

[John Scott]

wrong place to ask that question!

 

I have to agree with John: most people can't drive their STOCK 240 or whatever to 10/10ths before they start gobbing in more power.

 

More power makes you lazy as you think you can always "make up time" on the straightaways. Watch the old Corvette/Lotus battles of the early days of televised roadracing and you will see this laid out very well.

 

A balanced machine will ALWAYS be faster than one with just one good attribute. Building a car that you can never drive to it's fullest is both sad' date=' and a sorry waaste of good resources.[/quote']

 

Sorry, but that last quote got to me. Restrict yourself to only as much power as you can drive to the fullest? Very few people in the world have that kind of talent. HA! Since when did a trophy winning race car, and the ability to drive it to the fullest, become the only reason to build a HybridZ? Look at my face every time I get out of my car. I'm as happy as any car enthusiast in the world. No I'm not kicking Lotus and Porsches around the track, just enjoying the heck out of my wasted resources. Some of us really like being able to lay rubber by rolling on in 3rd. High 3 second 0-60s on my G-tech... starting in 2nd, mid 20s mpg. Goes way faster in a corner than I'm willing to try. Good springs, front and rear sway/strut bars, phantom grip, Nitto 555s make for a well balanced amout of fun. Never been on a track, never will, can't drive it 10/10ths, and still grinning ear to ear.

John

[JMortensen]

I took a friend for a ride on a twisty road in my Z. Coming up over a rise with a little lip at the top I got slightly out of shape, I took the 15 mph turn at ~50, etc. It was fun.

 

We get back to his place and he says: "You wanna ride in a really fast Z you should get a ride with Jason... his still has all the stock suspension but he's got a V8 and he just steps on the gas and it goes completely sideways!"

 

Different strokes for different folks I guess. I'm at ~240whp and I wish I had 300, but I think it helped that I built it up really slowly and didn't just jump into a Z with a whole buttload of power and then try to figure out how to drive it.

[Drax240z]

I think that my car at ~240rwhp is exceeding my driving abilities at times. At the very least, I know I can get myself into trouble with it easily. On the track, traction is a huge issue, but I wouldn't be any faster with more power. In fact I MAY be faster with less power. Some additional grip/LSD would go a long way.

 

Upgrading the brakes/tires on my car would go a long way to allowing me to stay out of trouble.

 

The track is one thing, but on the street it's so easy to overlook something (wet road, deer, other cars, road debris, etc) that I am not sure I NEED more power.

 

I guess what I am trying to say in a round about sort of way, is that if you build the car for the power, it's a whole different ballgame than just swapping a powerful engine in a car that isn't ready for it. I have a roll bar, strut braces, coilovers, bushings, larger anti-roll bars, etc, combined with good performance alignment setttings, and the car is fairly well balanced. It's controllable, I can drive it hard without surprises on the track. If I drive hard on the street, 100mph+ comes up very fast, and those wet patches/gravel can be quite... troubling, to say the least.

 

My advice (which I didn't follow well enough myself) is to build the car, then build the engine to suit the car you've built!

 

EDIT: Oh yeah, if you just want to smoke honda's and 5L you don't even need an engine swap!

[deMideon]

I guess it just depends if you think peeing your pants is exciting!

[Tim240z]

I guess it just depends if you think peeing your pants is exciting!

 

[fl327]

You should set a goal for yourself and work towards that goal deliberately and methodically, it is the most direct and the cost efficient way IME.

My example:

Im building a z to practice drifting, if I get any good at this I long to be able to smoke up the whole track with long smokies sideways.

I actually detuned my z to learn its true potential as an autox car and a drift machine. Until I get a competant understanding of the concepts of both I wont raise power. Right now I can drift the car fairly well but I dont get a smoke show, its more finese than brute power over technique.

My goal is just short of 300hp, right now at 182hp the car will do whatever I want slidewise, this is also due to a well oiled LSD and a guy thats owned 10 zcars and almost killed himself in all 10. My supporting mods, fuel pump, fpr, fuel lines, ignition, braking and driveline shold support 300rwhp fairly well, but at my current detuned state they combine to form an incredibly well running car that screams at me to turn up the boost, its a raging bull with a muzzle basically.

I know my goals and I have set the car up to perform, but only a ridealong track instructor deems me worthy.

[BrandonsZ]

I've been bragging to my wife that I'll have 20mpg when the swap is done... I was thinking a zz383 fast burn... (don't have the engine or the car yet, but very soon) now I'm thinking stock 350. I just don't want to deal with fuel injection, but all signs point to it!!!! I know I could build a mild 350 and get 20mpg, but... I really want a daily driver that drives like a funny car in acceleration, and a formula 1 on the turns, but gets over 20mpg.

 

*THINKING REALLY HARD, BUT ONLY SMELLING SMOKE*

[WickedWild]

I want enough to scare me. I want enough that it would take a buda like zen to maintain control. I am a gear head in its most basic form. Searching for pure unadulterated torque and power. I live for the smell of rich running exhaust fumes mixed with burning rubber. I am in euphoria when my car shakes at idle growling spitting fire daring anything on wheals to challenge it. No man who thinks he has fast car can resist revving his engine at a stoplight daring to hear the beast unleashed. Pistons pound in my sleep, oil runs in my veins. My flesh it burned, scrapped, and cut into this car. I know every bolt, every flaw; all of it’s potential. But I’m poor. How much power do I think is enough in a Z? How much money do you have? For me there is not enough.

[datsunlover]

You know.. I'd like to have more power.. but at this point, I'd probly kill myself.. heck, almost did a few times already! My car is prety much stock, and the suspension and brakes are almost worn out. This winter i'm gona rebuild the suspension, upgrade the brakes, and stifen the chasis a little..and add a 5 gear. I'm gona take the motor apart (valve seals leaking bad, oil leaks evrywhere, carbs not set proper) and do a bare bones 'rebuild' on it. I figure I'll pick up maybe 15-20hp, but having the rest of the car back up to 100% is gona make it FEEL like more power, and it'll be able to perform better. Heck, i'd leave my engine alone if it was good.. I think the rest of the car needs attention first. I know I'll want more later on, but for next year I'm only gona shoot for 200Hp or so. My car is fun in it's presant state.. I'm getting excited to think how much more fun it'll be after all this!

[jt1]

originally posted by johnc

 

There's only one V8 Z that I know of that can equal the ITS lap record at a race track.

 

John, can you give us any details on that?

 

Thanks.

 

John

[John Scott]

HybridZ has spawned another one. Quick, somebody give Wickedwild a shot of Nitrous, no, Nitromethane at 30 psi! Breath deeply, my son. Excessive hydrocarbons are necter of the Gods! ButlersZ, why the Scarab position if you want the best track handling Z? I though it was resolved that the JTR was best for balance in road racing, less weight on the nose and quicker response in the turns. Your "keep it sideways" sig and your wanting to blow away the usual street performance vermin makes me think you might be a power monger at heart. After all this is America, home of the stoplight wars,0-60, the 1/4 mile, and less than track smooth roadways. Remember, no one says you have to push the gas pedal to floor in an over powered car. Probably takes a better driver to know when and how much. I'm not swayed by an ITS champ. He probably dosn't give a hoot about a 10 second 1/4. Different road conditions/tracks favor different configurations. Where's your heart, at the track or on the street? The nice thing is a well designed Hybrid can really do both pretty well.

[Guest Z2nr]

I personally would build the car for about 250-300whp that is PLENTY in a Z. They are so light that even 200whp is fun as hell, it's not a Supra that weighs like 3600lbs that you need 400+++whp to run good times.

 

With 250whp you can run great quarter miles times and have lots of fun on the street. Personally for a street car you don't want too much hp, it kills the fun outta driving the car.

 

Over powering the car turns a very fun car into a sliding death trap on the streets. Personally I am going to just put an Sr20det in my Z, and get a boost controller with a high/low boost function, that way you can have your cake and eat it too.

 

That is why I like turbo engines, in my opinion they are the best option for a street car because you can adjust boost on the fly. Good luck with your decision making.

 

Watch what you wish for.

[Guest bastaad525]

200-250rwhp in a 1st gen Z is more than enough to embarass almost any rice rocket or most 5.0's w/o much fuss, actually enough to embarass probably 90% of the cars on the road, really. I have always said to myself that anything over 300rwhp in a 240z is a waste as it would probably be pretty difficult to drive it well, with that much power. At 230rwhp/300ft lbs in my car right now, I'm just starting to crest the area of real traction problems... I can control it well enough to launch nicely, but applying power and getting on boost in any kind of turn is... well... interesting to say the least And in such a light car, this power level was just enough to run dead even with a C5 Corvette which thought he was gonna cut me off going up a freeway onramp the other day... SURPRISE!

 

If I were going to the drag strip every week... I'd have really gone crazy and would want to get as much power as I could. As it were I wanted this car to be a 'mild mannered', yet capable, daily driven street car, and set my goal at a modest 250rwhp. Once I get my 'real' exhaust in there (running horribly restrictive 2.5" crush bent now) I should right at that point, and I think I'll be happy with that. Really... living just outside of Los Angeles, I wouldn't ever get a chance to use any more power than I already have anyways. That's what sux even as it is now, for all the work I've put into it, I really never get to use what it has anyways, save for sprints up the freeway onramps. Yee..... haw