Please dont flame for asking but im really in a cross roads where i can go either route. I have my twins already there in excellent shape with only 20K miles on them, they been ported by Pettit and are full non sequential.

I am shooting to break into the high/mid 11's in my FD this summer.

I have an excellent suspension setup I think.

I have the rx7.com Launch kit
tein flex coil overs
transmission and differential brace
and I will be running BFG drag radials at the strip

Hooking up should not be a problem (mydriving maybe since i havent driven the 7 at the strip ever)

anyways lets pretend I can drive pretty darn good in it.

and my car has pretty much every bolt on under the sun for the stock twins.
down to the intercooler to the downpipe to the HKS ignition system..

now my question is if i run therse twins at lets say 14psi or 15psi for that matter and get a propper tune.. should this car be cappable of running those times safely?

or should i ditch them now and just go single turbo??

reason i ask is I love the twins, they way the look sound, run everything. I have everything for them already also.. I have no ambition right now to really go faster than an 11.5 ET in in the quarter mile..

the motor I have is also a Pettit street ported motor.

can the twins get me there or should i not even try it?

 

From what I understand that's very possible.

 

ok cool.. i just dont want to waste my time with the twins if they wont do it.


plus i wanna be able to get a decent life out of them also.. and not fry in my first year.

 

well, the stock system is kinda... weak, you should never really go over 15 psi. I would suggest either swapping out to BNR Stage 3's if you wanna keep the sequential system or just swap out to a large single turbo, T70 or something in that range

 

Yes, it can and has been done on stock twins. However, I'll tell you right now that you are going to (eventually) break something at the strip. You'll need the following:

* Either a TII or a Kaaz diff
* Chromoly axles

RTS3GEN here on the forum ran an 11.77 a few years back. I watch him over the years break a lot of things to get to that 11.77.

 

actually mahjik.. the money ill save from not going single will actually fund my Kazz locker unit.

the stock axles ill have to deal with till winter tho sadly.

 

if im going to keep the twins.. i want my car to have pretty much the best of everything while running non-sequential twins for now.. maybe 2-3 years ill still go single but for now I might as well have fun!

 

As you strengthen one part (the diff), another part becomes your weak link (i.e. the axles). RTS3GEN broke his axle after his 11.77 run. He had already upgraded to the Kaaz, but snapped an axle on his next run trying to better his time. Well, I wouldn't call it a run as it didn't leave the starting line.

 

i got ya.. yeah maybe ill just get used to my car this year upgrade everything and do the axles when i get the money and then see what she will do!

 

plus i always thought the axles were good to the mid 10's i think hinson even says it on there site.. i was hoping i could get away from the axles at least for a year.. but i def know the locker is a must have.

 

Any FD quick enough to run 11's, has enough power to break the stock diff and/or stock axles.

 

understood sir..

ill just upgrade the diff, now and take it somewhat easy at the strip until i can afford the axles too..

or i can just not run drag radials

 

Yes, that is the other alternative. However, on stock twins, you'll need something to hook up the car on the launch to make it into the 11's. That "hooking up" is what breaks stock components. It's just not a drag car by nature.

 

Also running BFG drag radials will break stuff a lot faster than a true slick will.

As far as running 11.XX on twins, it's not that hard to do.

-J

 

If I were you I'd buy a spare set of axles and carry them with you to the track. Very cheap insurance.

 

^ +1 better safe then sorry!

 

Why is that? Sidewall differences?

 

Probably about 10-15 peopel over the years have gone 11.0-11.5s on the stockers. Some have done it on stock ports also. A lot of those guys later switched to singles and still run about the same E.T. but trap obviously higher. The stock twins are very capable to make a fd move down the track in a hurry.

 

excellent news and help guys! and thanks for not flaming me for asking, cause im sure its a topic thats been beat to death..

So pretty much i need to look into upgrading axles and the kazz and i should be safe for about anything id then run right?

 

Yes, a drag radials have a stiff sidewall which causes drive train "shock" under a hard launch. A true slick has a very soft sidewall and has a dampining effect on the drive train. The fact is you will always have a weak link.... clutch, input shaft, gears, output shaft, drive shaft, diff, diff case, diff gears, axles, suspension, wheels and tires all have to work together.

Also I would consider something a little softer than your coilovers.....

-J

 

what would u think for shocks/springs etc for launching if not flex coilovers?

 

There seems to be a big misunderstanding with fd owners and the whp/et ratio....
I've been 12.02 @ 113mph with 312 rwhp on 245/45 16 street tires. 11.XX is not as hard as people think, you just have to have a GOOD driver and the right setup.


-J

 

I'm only in the high 10s and i broken a chromoly axle, but busted7 is running better times than me with the same 60' and he is on stock axles.

 

Read this thread and search in the drag racing/race/suspension sections.
https://www.rx7club.com/rotary-drag-racing-167/proper-drag-suspension-541711/

-J

 

ok i think i know my setup ill run for the street/strip but its not set in stone.. im readin up on it for now..

now i gotta figure out my fuel system thats the only last thing i need and im thinking 4-850cc injectors will do well for 350rwhp?? you guys agree?