xsciuga

Ok, I've been told that the stock HP rating for 80-83 NA Zx's is 145@5200rpms...
Now my question, That is at the flywheel, correct? For some reason I have this idea in my head that it's at the rear wheels, can someone clear it up for me right quick.

Dorifto

The 145hp you speak of is at the wheels. If I remember correctly, the L28E puts out around 180hp to the crank in top factory-spec tune.

Bleach

1975-80 engines have 135wheel/170crank
1981-83 engines have 145wheel/180crank

That's just an overall average. Each engine will output differently based on condition or modifications. No, a K&N filter does not add 15hp.

DoTheDrew888

I saw several stock 280Z's and 280ZX's all dyno around 120HP. I figured the rating of 145HP was flywheel power based on the dyno results. I don't know, but all the cars were basically stock or completely stock and well taken care of. The fact that they were all almost right at 120HP makes me think those ratings were flywheel though.

xsciuga

Wow, I'm excited then so I'm actaully making like 160ish to the wheels..maybe more Sweeet..Who needs AC and power steering when you can go fast!

xsciuga

a K+N dosen't, but a cam does..It sounds like theres a mean cam in it..But I can't be sure, ya know.

s/cL3.0

You only gain a total MAYBE 4 HP to the wheels removing belt accesories.The AC only takes up HP when it is in use.

xsciuga

I doubt the "4hp" figure, underdrive pulleys are found to add 10Wrhp. So how is completly removing them going to result in 4? Not to mention cam is said to gain 10% hp..so We're talking 198ish at the crank..160wrhp is VERY plausible here. 160 is even low, you're not gonna loose 20% w/ no assecories and a 5spd.

Skully

"said to gain"

you will never know unless you dyno it, then put one on your car and dyno again...


see where our conclusion comes from??

they advertise...
exhaust ADDS UP TO 15 HP...

yeah it adds 15 HP if you have SHITLOAD of other work done to your car that actualy is able to use that exhaust...and even then...its a questionmark...ya know...

xsciuga

I totally agree with you on the dyno thing, it's all talk until you get the numbers. However..exhaust is diffrent from freeing up hp at the rear wheels, exhaust is giving you Hp you don't have yet, removing assecories is just using Ho that you allready have diffrently.

Skully

iw as using it as an example

s/cL3.0

Aftermarket underdrive pulleys are usually lighter and smaller in diameter that is why they gain HP. but if you do not use a/c while your racing your probably only picking up a half HP. There is nor real gain in removing your accesory belts.

DoTheDrew888

Maybe I'll test that out next time I dyno.

Bleach

right, like the exhaust is shooting out faster so the airflow pushes your car?
Power is made on the intake side, not the exhaust. Allowing more freeflowing exhaust frees up backpressure. If the intake is only getting so much air and fuel, it cam only make so much power.

A performance cam works well only when it has the bennefit of more airflow in and out of th engine. The cam will allow more air to actually enter the cylinder. At that point, you can use slightly more fuel and that is where you start to get some good results. Sticking a cam in a stock engine does not add 15 horsepower...

except in a Honda. But you have to add a Crane Cams sticker on each fender too.

xsciuga

I suppose the only real way to put this to rest is to dyno. Stickers add like 5hp a peice though. Not to mention the 15hp I get from my 6ft wing. However.."usually lighter and smaller in diameter " the logic you're using is, smaller pulley= taking less hp from crank to turn them..so how would completly elimnating the assecories only add 4Hp? I guess I'm just not following. I'm probaly putting power steering belt back on today..I bought the car and it didn't have a tensioner for it, but I got one for free from the junk yard. so eh. Oh my steering wheel is just metal now, so it's a real bear on your hands combined with no power steering haha....I think my friend has the roller connection..Maybe I'll go dyno this week with him. Then again, he has an SS...I'd feel bad lol.

Bleach

Theoretically taking the belt clear off would free up more power than an underdrive pully. I believe underdrive pullys are overrated though. Typically they are just for the alternator and fan.

I did remove my AC belt, and then removed the belt from my power steering one time that I had a big leak in the power steering hose. I noticed more torque right away and got about 1 more mpg. Not enough difference on the high end to tell without a dyno.

Dorifto

I always assumed the underdrive pulleys were used for racing applications where high revs are common for extended periods of time. Something about saving the accessories from unneeded abuse. I dunno, I got a set of pulleys for my Sunbird for $3 one time, and I didn't notice a difference, other than the power steering being harder to turn, and my Alpine amp suffering for current.

Now, if my L spun to 9500rpm and still had PS and AC, I would probably invest in pulleys. Otherwise, stock works just fine. I know for a surety that my Rx7 needs a pulley [8500rpm is tough on alternators not built for over 7500, and no PS from the factory].

s/cL3.0

The most power gain I have realized on my ZX before I rebuilt the bottom was I removed the cluth type fan {it was stuck together all the time} replaced with an electric fan and added the MSA Intake. I dont know how much it added but I could feel a huge difference. On the whole removing belt thing I am just saying It is not alot of HP to the wheels especially not the A/C that only sucks up power when it is on.

xsciuga

You also have to remember although it's the same engine, each specific one reacts different to diffrent things. All cars are diffrent, and perform diffrently. Like I said though, All we're doing is hear say until we dyno, I'll try to set it up though. I do know however that trading off for an electric fan is said to net around 7 wrhp. My buddy did it on his 69 camaro w/ a 327 and picked up 8 I think, he said you could fill the difference, but it wasn't like it'd be enough to break your neck.

xsciuga

Oh by the way, that 327 is crazy fast! It's unreal, he has 4.56's!!! Dang. talking low 7's in the 1/8

Bleach

I thought the AC didn't pull on the engine either. One time when I was changing my belts, I just took the AC belt clear off since the system did not work. I gained an average of 1 to 1.5 mpg with no noticable power increase. I think just turning that belt and free spinning pully at freeway speeds takes some amount of load on the engine.

HybridS130

hmm i've been thinking about getting rid of the clutch fan, mainly because all you hear when i pop the hood is the fan. you can't really hear the intake sucking in air and you can't even hear the exhaust when i rev the throttle. i hadn't really thought about a hp gain that's great though, how hard was the swap? price? did you use a thermostat or a switch?. . . . . as soon as i get ahold of a welder im gonna start looking for a new daily driver and tear apart that Z so she'll be nice again, im trying to get together a whole bunch of idea and this one sounds good

Dorifto

If I remember right, the old 240/260/280Zs had 102-amp alternators ... If I remember correctly, there were upgrades to 120-amp models. Wouldn't that be enough for that Lincoln Continental fan swap? Again, if I remember reading right, they drew 100-amps when started, and pulled 20-40 [can't remember] at full speed, and they move something like 4000 cfm! Now that would cool the radiator.

I'm set on swapping to an electrical fan as well, I hate having the fan clutch sound louder than my straight-pipe side-exit exhaust ... ugh.

whyfeel

MSA has an electric fan kit w/thermostat for about 150. I don't know how well it works, but that would be a very interesting comparison.

Bleach

I don't know about the 240Z, but the 280Z and 280ZX all had 60amp alternators.
Some books say the 280ZX turbo had 70amps but all the replacement alternators for them I see are just 60amp.