This is my first post here, so please don't flame. I gotta buddy at work who is planning on rebuilding the engine to his '93 Rx-7 and converting to a single turbo. He said he'll have something like 412 hp at the wheels. Question is, assuming he's on street tires and a fairly good driver, where will his quarter mile times be? I wanted to get an idea of how my Z will stack up to his. Thanks guys.

 

How modded is your Z and what exact single turbo is he getting and what psi does he plan to push?

 

Pound for pound the 7 will kick Z ***. Of course you'll run into less trouble with the Z mod for mod.

Use the Weight/Power ratio. (vehicle weight)/(HP)=Ratio

Car with the lower ratio will win. Good luck!

 

I don't know the Turbo that he is going to run, nor how many psi he's gonna run either. I'm not too familiar w/ the RX-7 yet. I figured all of that wouldn't matter too much, and knowing the wheel hp estimates would be enough to get a good estimate.

As for my Z, it'll probably be in the fall or early winter before its completed. (his car won't be completely ready for a while either) Rebuilt engine w/ upgraded internals. I'll be running JWT Sport 530 BB turbos. Should put down 480rwhp plus (maybe 500whp) w/ proper tuning. These turbos are fairly new (not a lot of info out yet on em), but I would expect to see full spool w/ these turbos somewhere between 3k and 3.5k rpms, faster than stock. Obviously bigger injectors, intercoolers,full exhaust, clutch, etc...... are on the mod list. I'm doing all of this at once. The Z will probably weigh around 3400 lbs., maybe high 3300's. I wish it weighed 2800 like the RX-7 =)

 

Stock Z turbos spool above 3.5k? Makes non-sequential FD turbos look lag-free.

 

Sounds like both of you guys will have some pretty quick cars--assuming neither of you roasts the tires off the line that should make for an interesting race.

 

I meant stock turbos will hit full spool at 3500 rpms.

 

The -7- CAN'T Lose!!!!

Sorry your Z is going to be humilated. Welcome!!! The Rx7Club Knows about you!!!

 

I would agree, your car with 500hp could run a 300hp rx7 and the rx7 will humilate a z. This is not a ******** response or anything. The 7 is just so much lighter and the power band of a rotary is just sick. They are great high rev cars, and once they get moving they are scary quick. I would say the race will be good but I highly recommend you dont put no money or anything on the race because you will probably lose it

 

I don't think so. 400lbs isn't compensating for an extra 200hp.

300zx w/500hp vs a 7 w/300hp? ZX is gonna whoop on it.

Now a 410 rwhp 7 vs his 500hp ZX machine. The rx7 will get the launch and the ZX will pull on it.

 

oh by the way fellas, check this out, the above post mentioned a power to weight ratio....
FD = 2800/412 = 6.796
300zx = 3400/500 = 6.800

Pretty close, huh? Getting 500 at the wheels might be a litte tough for me though, 490 might be a little more realistic. I guess its a question of how long the race will be then, the 7 will pull me on me off the line that's for sure.

 

If its 91+ Z it weights 3500 not 3400. Also, my rx7 weighs 2712 lbs. After we lose the stock exhaust stuff, get lighter battery, etc, we are pretty light. Actually , I have 2 sets of carpet installed and I'm only 2712.

 

I have heard that the Z's have a nice top end....so it depends on what type of race you are gonna do. But then again the top end on the 7 isn't bad either

 

If you have lightened the car a little, why couldn't the ZX guy do the same?

 

I did nothing to make my car lighter intentionally. Just from replacing the exhaust and stuff. Ok, my battery is 25 lbs vs 40 from the stock one.

Its just stuff like the 40 lb Precat, that we replace with a 8-10 lb piece, etc. Look at the Z, it has 2 of everything. An aftermarket exhaust is going to be just as heavy.

David

 

Yeah, my car weighs like 3475 stock (I think). Just my upgrades alone (full exhaust w/no cats, lighter flywheel, etc. should bring it down to 3400) I believe that taking out the spare tire and jack removes something like 40 or 50lbs. In fact, If done correctly, one can remove close to 300 lbs on a Z with the full interior in perfect order.

 

Hmmm, intentional or not it still got lighter and the Z can do the same. I don't see any difference since the Z has 2 of everything and the 7 only has 1. If he replaces one side of the exhaust and gets rid of the cat and saves 10lbs on one side, it's going to be the same on the other side. Maybe I'am missing something but just because it has 2 of something it can never buy lighter parts?

 

I doubt the Z's exhaust is going to get much lighter. I'm sure that Nissan did everything they could to keep the Z's girlish figure.

 

And no.... An aftermarket exhaust will not be "just as heavy." let's say the precats on my car weigh 40lbs. Now, times 2 you got 80. I guarantee the dp's don't weigh more than 15 lbs. I actually cut out MORE weight than the 7 would have.

 

 

you are making the assumption that Z downpipes weigh 40 lbs. Neither of us know thats true. So you are just guessing.

 

Its all about the top end/speed power.. z's are slow and slugish on the top end. I have a friend who has everything done to his. HKS Turbos, intercoolers, exhaust everything. He puts down somewhere around 480whp and I take him all day long running with my boost turned down to 10lbs.

 

You are correct. I have no idea how much a precat or main cat on the Z weighs. All I know is that when all four are off my car, then it will be substantially lighter. Oh by the way, you made the assumption that the Z's exhaust "isn't going to get much lighter." That, my friend, is far from the truth. Sorry.

Also, my original post was questioning 1/4 mile times on the RX-7. Anyone got any ideas?

 

to answer your question, with 412 to the wheels he will have a 122-124 trap speed. thats all you need to know. ET will be based on driver skill/traction.

 

Cool, thanks for the feedback