Sudox_E

Well, I've seen many a thread speculating hp, quarter mile times, yadda yadda... Well, here's my thread. Do you guys think 13's are possible on a sp 12? Little to no weight reduction, with a racing beat road race style based exhaust and a holley 465? If its well tuned, and you get good traction, I'm thinkin high 13's/low 14's is very possible. I will soon be running a similar setup, thats why I ask...

Directfreak

iTrader: (2)

No.

mperformance

hell no...I'm lucky now to be @ approx. 14.5 with 2150lbs (read LIGHT) 12a streetport and lots of tuning...

my guess with no weight redux, properly tuned and traction, low 15s to high 14s but not close to 13s ever. For 13s you need a bridge port and weight redux...

poweRX-7

or a TII streetport in a first gen....
hey, dreams can come true! if money permits
jeff

Pedestrian X

what would times be if it were say a 13B w/ large SP?? under same conditions..

mperformance

possible low 14s to high/mid 13s, but again it depends on weight/traction.

Cloud

Don't forget, at the track, traction is everything...street ported RX7's can be finicky to launch correctly, and it would require both sticky tires (slicks or drag radials) and some finesse to be able to knock down some good 60 foot times.


Remember, the only difference between a 14.5 @ 100 and a 13.80 @ 100 is TRACTION and DRIVING SKILL.

A compliant suspension (read: loose), sticky tires, good tuning, and great driving are the only way to maximize your quarter-mile timeslips.

That being said, we have yet to get my brother's mild SP 12A (Holley 465 and RB exhaust) into even the low 14's due to tuning issues and traction, so it's obviously not easy! :P But i DO think the potential is there...

Sudox_E

hah, thanks for the enlightening response....

Anyways, how many horses would such a setup be pushing, if it was properly tuned? Still, I'll continue being optomistic and naive, we'll see what I run this summer A certain amount of weight reduction has been done, much lighter exhaust system, no storage bins/sound deadening, no ac. I know it's not much, but I guess every little bit helps.

fatboy7

You asked a yes or no question.....

Amagi82

with weight reduction YES, definately. Without, its gonna be tough.

12abridgeport

I personally seen a '79 with 13b 4-port stock port (12a side plates) running 14.0 on slicks, so a S/P should be able to do at least 13.5's.

Metallic_rock

to use a little science... the less inertia your vehicle has to overcome, the faster it will get to that finish line.

Common terms? pull as much crap off that car as you can.

FD Racer

~170 hp

MIKE-P-28

iTrader: (1)

nightmare is more like it, see ya at the 20k mark Im almost there

BRealistic

I assume these FBs with big bix in them are the result of: "I got the car cheap, but I put the money in to it as I get the extra dough, and it adds up."? Right? I just don't understand why spend $20k on an FB when you can buy a sweet FD for that.

And not to diss those who drag sevens by any means (I know it is cool to be different), but why buy an FB RX7 -which was specifically designed by Mazda to be a great balanced handler on a budget with 70's technology- and try to make it into a drag car? Doesn't that ruin the handling of the car when you set it up for drag launches?

That brings up the question: Do FBs have any advantages over other more cheaply tuned cars in drag racing? I am not criticising, just trying to learn.

12abridgeport

Actually that same balance you are talking about helps 7's in drag launches as well. With a stock rear end and street tires i get a 2.1s 60 foot time. But anyways, unless i have a full suspension done for drag racing and some really skinny tires in the front, it's very easy to make it into a cornering car if i had to.

Rxmfn7

iTrader: (4)

Id rather use a FB or SA for drag racing than any other rx-7. They were the lightest, and had the solid rear axle.

Sudox_E

well, I'd be happy with a low 14 at this point. I was under the impression that the setup i was talking about would yield around 190hp. Anyways, looks like I have work to do... thanks for the help guys

tomsrotary

a fella in NZ (new zealand, close the australia) has run low 12's in a J-Port (race port) 12a. he is a very smart guy, and was able to tune it presiley, and have decent drag diff ratio - 4.4:1 - 4.8:1. i doubt that u will run 13's, thats what is expected from a stock 13b turbo in a gen1 with no weight redux.

rollin82

i have a friend here in tucson who ran a 15.2 on 16inch wheels and 45 series tires.... the jist of his mods were.. 12a streetported. webber 48 (i think) custom headers and full exhaust.... the sad thing is a few weeks later his engine had a electircal fire

he was a pretty good driver.. and i suck at launchin my modded gslse and he kicked my *** many o times haha

there is my .02

Cloud

Update:

FYI, we took the car I was talking about to the track tonight. It was a crappy test-n-tune, and there was very little traction. The best run was a 14.8 at almost 93, with a shoddy 2.3 60 ft. time.

However, high 13's on this set-up, NA, are a certainty. Car was 2420 with driver and over half tank of gas. Mild streetport (with 60k miles on rebuild), RB exhaust, Holley 465, poor tuning and stock crappy ignition at unknown timing. Traction with the crappy Sumitomo's and autocross suspension was hard to come by - on the best run, I spun completely through 1st and most of second. I powershifted and held third through the traps. :O

Some more weight reduction, traction, tuning, and mods (ignition system will be installed within the week!) and this is MOST DEFINETELY a high 13 second car. After it runs that number, a small shot of juice will knock it down to low 13's.

Thought you might like to know that your goals ARE attainable, it's mostly about the tuning and driving skills - which take practice!

Now I am going to copy the same set-up on my daily driven 82 GS, which was running high 16's in comparison - yuck!

REVHED

Nice time. 13's will be no easy task but some people are too quick to say something can't be done. There was a quy on Mazspeed and here a while back who ran low 13's with a stock port 13B. Like you said a lot of it is and tuning and getting a good launch.

Sudox_E

wow, it's great to hear some opinions from some open-minded people. 13's would be heaven for me, even if it is a lot of work. Maybe with some drag radials, a little weight redution, and a lot of patience, I could prove a few people wrong

sudox_e