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-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   Is it Possible to for a 13b without turbo, supercharger or bridgeport to do 160mph?? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/possible-13b-without-turbo-supercharger-bridgeport-do-160mph-904800/)

hashman626 05-23-10 12:37 AM

i appreciate that Primos003, i don't know how it didn't show up for me??
and nate91242, that's an interesting comment. I once did 96 mph in a chevy beretta, it felt about as fast as I was going in my rx7 (120mph). I don't believe my speedometer is that far off, rather the suspension on the beretta is very soft and on the rx7 quite stiff but could you or anybody else suggest an aftermarket speedometer which is wickedly accurate??

KidA 05-23-10 02:57 AM

i just did 120 in 4th with 1.5k room left on a bridge tonight.

RTRx7 05-23-10 07:10 AM

Get the one that Brian had on the fast and the furious.

If he can get his eclipse to 160mph, you can do it too.

R_PROWESS 05-23-10 07:28 AM

i hit 138 with a 6 port n/a with secondary ports stuck closed so (all she had in her).. definitely

Valkyrie 05-23-10 08:12 AM


Originally Posted by keithrulz (Post 10013008)
i hit 138 with a 6 port n/a with secondary ports stuck closed so (all she had in her).. definitely

You were probably doing closer to 120 actual speed.

Spirit-RE 05-23-10 08:19 AM


Originally Posted by hashman626 (Post 10012772)
and nate91242, that's an interesting comment. I once did 96 mph in a chevy beretta, it felt about as fast as I was going in my rx7 (120mph). I don't believe my speedometer is that far off, rather the suspension on the beretta is very soft and on the rx7 quite stiff but could you or anybody else suggest an aftermarket speedometer which is wickedly accurate??

Just use a GPS.



Beretta at 90+? Yeah, I'd be afraid to go that fast in that car... lol

jjwalker 05-23-10 09:02 AM

My brother and I did 160 once in his 3rd gen drag car (yes, he drove it on the street). If I remember correctly (this was 10 yrs ago) he was running a single turbo swap dialed in at 20psi, haltech, 3 inch exhaust, coilovers, ceramic apex seals and probably alot of other shit I don't remember. I was only 14 at the time. The car was built by Don Marvel. Full roll cage and all the safety equipment, even a clutch shield because redline raceway wouldn't let him drag without it.

Anyway, we where going up I-35 to see my grandma in Oklahoma and he got a wild hair...

Since then, I still don't want to go that fast. We'd go over the little hills in the road and it felt like you where going to take off like an airplane, and this was a drag car. I can't imagine stock aero and going that fast.

scathcart 05-23-10 11:33 AM


Originally Posted by Valkyrie (Post 10012057)
There's simply too much air resistance and not enough power. If you had maybe 300 HP it would be possible.

Its actually about 265 flywheel hp to go that fast.
Here's an example of an N/A streetport build that makes that kind of power.
https://www.rx7club.com/naturally-aspirated-performance-forum-220/make-230rwhp-streetport-13bre-n-818133/
A bridgeport/PP would make that kind of power even easier. You'll be hard pressed to do it with a 6 port engine, though.

You should, at the very least, lower the front of the car so its roughly an inch lower at the front with respect to the rear. This will help to reduce aerodynamic lift.

Turbo23 05-23-10 01:07 PM


Originally Posted by scathcart (Post 10013279)
Its actually about 265 flywheel hp to go that fast.
Here's an example of an N/A streetport build that makes that kind of power.
https://www.rx7club.com/showthread.php?t=818133
A bridgeport/PP would make that kind of power even easier. You'll be hard pressed to do it with a 6 port engine, though.

You should, at the very least, lower the front of the car so its roughly an inch lower at the front with respect to the rear. This will help to reduce aerodynamic lift.


265 hp is about right, my speed 3 makes roughly that, and Ive been up to its top speed, 155 (with GPS) Took some road but it can do it.

Sideo 05-23-10 01:15 PM

buy an FD i hit 160 before i get to the bottom of the freeway onramp

2slow4stock 05-23-10 01:57 PM

A stock block can do 160mph+. But not without a turbo./thread

Valkyrie 05-23-10 02:00 PM


Originally Posted by Turbo23 (Post 10013401)
265 hp is about right, my speed 3 makes roughly that, and Ive been up to its top speed, 155 (with GPS) Took some road but it can do it.

More power, more torque, way more power to the ground (FF), and modern aerodynamics. But you still didn't reach 160!

Valkyrie 05-23-10 02:02 PM


Originally Posted by scathcart (Post 10013279)
Its actually about 265 flywheel hp to go that fast.
Here's an example of an N/A streetport build that makes that kind of power.
https://www.rx7club.com/showthread.php?t=818133
A bridgeport/PP would make that kind of power even easier. You'll be hard pressed to do it with a 6 port engine, though.

You should, at the very least, lower the front of the car so its roughly an inch lower at the front with respect to the rear. This will help to reduce aerodynamic lift.

A streetport is not a stock block! A bridgeport/PP is most definitely not a stock block.


BTW, every time you increase downforce to keep the car from taking off at 160, you decrease the chances of actually reaching 160.

NightHawkR 05-23-10 03:52 PM

Seriously why would you use ur NA 13b to drag anyways..... for all the money u need to throw into it to hit the speed u wanted (tires, port, aero, fuel support, etc..) you might as well do a turbo swap or 6 port turbo. And if you have that kind of time and money to spend on the NA block... i would take that FC to do some road coruse instead... just my opinnion.

rbharris1984 05-23-10 05:08 PM

As far as I know my 12a in my sa is stock and I hit 90 in third pretty quick.

R_PROWESS 05-23-10 05:12 PM


Originally Posted by Valkyrie (Post 10013024)
You were probably doing closer to 120 actual speed.

ya probably, i did have aftermarket rims on...

hashman626 05-23-10 07:56 PM

@KidA, thats cool man, ill compare that to a stock block S5 motor. apexi power intake is the only mod
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hashman626 05-23-10 08:15 PM

my bad kidA, i totally read your comment once until a sec ago, i thought you were talkin about a bridgeport haha but thats my vid anyways

jon0886 05-23-10 11:35 PM


Originally Posted by nate91242 (Post 10012024)
The stock speedometer is horribly inaccurate over speeds of 75. Just sayin.





And to the OP:
Just put the 7 on a cargo plane.
Done.


thats why i didnt say i actually went 160. just said the speedometer hit it.

scathcart 05-24-10 01:34 AM


Originally Posted by Valkyrie (Post 10013464)
A streetport is not a stock block! A bridgeport/PP is most definitely not a stock block.
BTW, every time you increase downforce to keep the car from taking off at 160, you decrease the chances of actually reaching 160.

I'm aware a streetport is not a stock block. No one, including the original thread starter, mentioned a stock block, so I don't know what you're talking about.

As well, I never mentioned increasing downforce, I mentioned reducing lift. It is definitely possible to reduce lift without increasing aerodynamic drag. Venting the engine bay out the wheel wells, putting a full belly pan onto bottom of the car, and lowering the front end of the car will all decrease lift with zero increase to drag.

Downforce is the aerodynamic force downward on a car, lift is the aerodynamic upward force. The two oppose each other, so you can keep downforce the same, and reduce lift, and net the same total results without the typical associated drag result of increasing downforce.

rotordad 05-24-10 01:29 PM

I have been to 160 & above in a few cars, only one FC though. Nothing special really & no point in making a goal like that in stock FC. 160 in a FC is very possible if worked. Using a GPS is a pretty good idea.

Valkyrie 05-25-10 10:06 PM


Originally Posted by scathcart (Post 10014481)
I'm aware a streetport is not a stock block. No one, including the original thread starter, mentioned a stock block, so I don't know what you're talking about.

The topic said "without a bridgeport," I simply took it even further to that it's even more impossible without a street port.



As well, I never mentioned increasing downforce, I mentioned reducing lift. It is definitely possible to reduce lift without increasing aerodynamic drag. Venting the engine bay out the wheel wells, putting a full belly pan onto bottom of the car, and lowering the front end of the car will all decrease lift with zero increase to drag.
Generally you reduce lift by preventing or slowing airflow under the car, which increases the airflow around the rest of the car, which increases drag. There is no such thing is a free lunch in physics.


Downforce is the aerodynamic force downward on a car, lift is the aerodynamic upward force. The two oppose each other, so you can keep downforce the same, and reduce lift, and net the same total results without the typical associated drag result of increasing downforce.[/QUOTE]

If you're trying to get to 160 with limited horsepower, you need to reduce drag, even at the cost of higher lift. You'd be better off taking the spoiler off, putting dimples all over the car, removing the windshield wipers, and taping up all the body seams than you would raking the suspension.

rx7racerca 05-25-10 11:52 PM

I'm going to go ahead and say NO to the OP's original question. Here's why: aerodynamic drag, the major factor governing top speed once you're over 90-100 mph (as opposed to weight) increases with the cube of speed - meaning a doubling of speed requires a quadrupling of horsepower. The stock S4 na was tested reaching 128mph with 146 hp by contemporary magazines (the S5 na, with it's additional 1000rpm of rev range and 14 more hp, gained a whole 2mph to come to an even 130mph). 128 to 160 mph is 25% more speed, or 1.25 times the original top speed. The cube of 1.25 is 1.95 and change, meaning 1.95 times more power is required to go from 128mph stock to 160mph, which means 285hp (flywheel, mind you, so 242 rwhp, assuming an optimistic parasitic drivetrain loss of only 15% - 20-25% is probably more realistic). Which means even the impressive heavily ported and modded na 230 rwhp number in the thread linked earlier won't get the job done, although it could come close.

NOx- how long are you going to shoot NOS to gain that speed? 30 seconds? A minute? Don't think so.

RTRx7 05-26-10 10:45 AM


Originally Posted by rx7racerca (Post 10018817)
NOx- how long are you going to shoot NOS to gain that speed? 30 seconds? A minute? Don't think so.

It's NOS.

Pronounced Nawwss.

Learn some respect.

As long as its not a double shot, he'll be fine.

Spectrum24x 05-26-10 11:14 AM

get a sportbike


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