power drag at 80mph, climbs slowly, help!

[dropped99gs]

Okay, so the basics - 99 gs anniversary edition- basic bolt ons (cai, 2 1/2"cat back, tsudo fireball muffler, Accel plug wires, ngk plugs) - B&M short shifter - lowered about 2 1/2" inches, JSP Terminator wing, OZ F1 16" wheels

I purchased the car a few months ago for $1500 w/ only 94k miles. in great shape, anniversary oz edition, reason so cheap was b/c the car had sat for over a year. All service records were in the glove box and everything seemed in order.
Immediately, i drained and replaced all fluids, filters, valve gasket, spark plugs, went to exhaust shop and had 2 1/2" cat back made and tucked under nicely due to high centering some parking lots and speed bumps. Car is really really low, previous owner (original owner) had hit the oil pan a few times so i replaced that as well.

Now the problem so to speak. Car runs great, shifts flawless, no issues. BUT - when i downshift and get on it it goes but just seams as though she should have more pull. When wrapping out 3rd gear it takes a lil bit, and i can't push past 120 in 4th to 5th. On take off its nothing impressive but she does get up and go, 1st gear wraps past redline flawlessly, 2nd pulls hard, no smoke from exhaust, idle's perfect.

I've watched youtube vids of top speed run same car (essentially) but my car just doesn't seems to have that top end pull.

I reviewed another thread on there where aerodynamics were discussed.

Could it be - due to my car being exceptionally low - (not sure of suspension, came with car - looks to be KYB struts with tein springs but the drop seems to be more extreme that what tein offers - ), the JSP terminator wing, and the added weight of myself and subs bringing the total to about 3600lbs, all factored in together limiting my top speed?????

What can I troubleshoot myself and see what it may be?

 

[Bud92gsx]

So what is the question..Why can't you pass 120, or that it climbs slowely past 80 mph?

You do realize you drive a n/t that weighs 3600lbs..Both of those are definatly factors..

 

[RoryBarron]

You can troubleshoot why you are doing over a hundred on a public highway and endangering other people along with yourself. That seems to be a pretty big problem to me.

 

[dropped99gs]

problem is the climbing slowly after 80+ mph.
primarily after 5,500 rpm in 3rd =
i mean is the n/t really that horrible?? i've built a 2000 civic si back in 05 and before i even put an intake on, that car would do 140mph.....
i bought the GS b/c i needed a car and it was tax time. was looking around for a good deal w/ low mileage.
I had enough to get a GS-t or GSX but not one in good enough shape i could rely on it after purchase w/out putting work into. I have been on the look, and will continue to be. for a turbo model for the right price and mileage. at that time i will sell my gs and join the turbo club.
if not, hopefully by this summer i can put a few stacks away and go turbo. And hopefully by christmas have everything sent off to get ported and polished, bored, necessary components for high boost.
i dont want something to drive 100mph everywhere i go, i usually set my cruise to keep myself out of trouble. but when i want/need to downshift and accelerate i want some oompf.

 

[96 420a-t]

You drive a n/t. 80+ is about all the stock 420a has in it. Im sure your aftermarket wing causes a bit of extra drag too.

 

[Bud92gsx]

If the SI was a hatchback I could see it doing 140, but theres really no need to go that fast..Also I bet the SI didn't weigh 3600lbs either..

 

[my dreamt dsm]

Sorry to tell you but that's how it is. I'm not sure about the speed governor on n/t models?
My single cam civic never had problem with the 420a's so you can compare what I meant

 

[96 420a-t]

Side note where are you getting this 3600 pound bs.? These aren't american cars. Mine weighed in at 3180lbs. With me and a heavy stereo.

 

[dropped99gs]

You can troubleshoot why you are doing over a hundred on a public highway and endangering other people along with yourself. That seems to be a pretty big problem to me.

i know stretches of highway where population is minimal and traffic is almost nonexistent for starters. i dont weave in and out of traffic and rarely even push past 80 mph.

what are some at home troubleshooting tips ?


I've already checked what i know to check, i.e. - plugs, throttle body etc.

Side note where are you getting this 3600 pound bs.? These aren't american cars. Mine weighed in at 3180lbs. With me and a heavy stereo.

wikipedia has the weight at around 3200lbs, figure 200lb for me, and 200 lbs for stereo.

 

[96 420a-t]

There really isn't anything to check. You drive a n/t. That's about all they are good for.

 

[dropped99gs]

looks like im going to have to settle for where it's at (for now) i achieved my goal with the car already, which was to establish a reliable vehicle for every day.
for being dropped as low as it is it rides like a dream. not choppy and harsh, it's smooth and even.
The wing i'm sure adds some drag and force, but works with the wing when i get up to speed going around corners and keeps the car seated nicely on the pavement.
The engine is solid and just turned 100k. so piecing together the required parts to go turbo or hopefully a gst or gsx crosses my path that is the right deal for me, is my direction now.

 

[96 420a-t]

I stay planted when I corner but most of my cornering is done at 20- 30mph. I never seen a reason to put a wing on a car that understeers as it is. You would probably handle better without it, unless you have something to apply downforce in the fromt as well.

Edit: You can't count wiki. 3200 is the awd weight. The n/a's weigh just under 2800.

 

[brandonwh64]

Since it is low miles and given you sound like you trust the engine, i would get a good turbo setup like hann or garrett and run around 8 PSI. That should show you some improvement

 

[laserspeeddemon]

You can troubleshoot why you are doing over a hundred on a public highway and endangering other people along with yourself. That seems to be a pretty big problem to me.

This.^

Actually I have made it a point to not help people fix their car who troubleshoot/tune their car on public roads. You can try to justify it all you want, but it's dangerous, illegal and stupid.

So have fun figuring it out for yourself.

 

[DSMTyson]

Side note where are you getting this 3600 pound bs.? These aren't american cars. Mine weighed in at 3180lbs. With me and a heavy stereo.

Actually, these are American cars...

Made in Normal, Illinois.

__________________

OP, Why the hell else would they recirculate them from the factory if there was no point in doing it? Answer me that.

 

[GRAVEDIGGER]

Quite trying to top out your car on public roads. There.... Problem solved

 

[dsmrollerz90]

Okay not to be mean but I have a strong feeling that these are the type of guys we hear about on the news street racing and crashing. Good luck to you buddy, dont do anything to hurt anybody else.

 

[BigBeans]

OP, from a quick calculation it takes about 35whp to overcome drag in a 3600lb DSM @ 80mph.

By 120mph, it takes 105whp to overcome drag, which is probably all you have, meaning on a flat road with no wind, 120 is about the max you'd ever see if you had all eternity to get there.

As you can see, the faster you go, the less power you have available to accelerate the vehicle, and the number changes very quickly as speeds increase.

You can troubleshoot why you are doing over a hundred on a public highway and endangering other people along with yourself. That seems to be a pretty big problem to me.

 

[snowborder714]

i know stretches of highway where population is minimal and traffic is almost nonexistent for starters. i dont weave in and out of traffic and rarely even push past 80 mph.

This doesn't matter - it is still breaking the law. The only place we condone going more than the speed limit is at a track. There will be no more discussion of this going forward. If you mention testing/tuning/speeding on the highway again, the thread will be shut down.

Everyone else, enough with letting the OP know it is unsafe. I appreciate everyone chiming in, but we don't need to build up his whole thread with comments about it. Anyone else that posts about it will have their post removed.

 

[dropped99gs]

This doesn't matter - it is still breaking the law. The only place we condone going more than the speed limit is at a track. There will be no more discussion of this going forward. If you mention testing/tuning/speeding on the highway again, the thread will be shut down.

Everyone else, enough with letting the OP know it is unsafe. I appreciate everyone chiming in, but we don't need to build up his whole thread with comments about it. Anyone else that posts about it will have their post removed.

I never once said anything about it being on a public road. And no, i do no street race......... anymore. stopped in 2005 b/c i saw some kid NEARLY kill someone. I was young, dumb, and full of kum then.

Where i above mentioned knowing stretches of road where population and traffic were no factor was just in reply to the above mentioned accusation that i was conducting my tests on public roads.
Therefore it is was assumed and never confirmed nor inquired where i topped my car out.

My intentions are not to drive around speeding where ever i go, but to get some troubleshooting tips and advice.
Not troubleshoot by taking it out on the street and running it like a mad man everywhere.
My intentions are to make sure my car is running proper.
Maybe my testing methods learned are different than what others on here may know, considering this is my first dsm.
When testing/troubleshooting what should i look for with a dsm engine? whats typical?

^ That was the point of my post, not to see how fast i can get my car to go on the streets.


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[snowborder714]

You said highway in the first post. Unless you have your own private highway, then it's a public road. Whether there is a large population or a lot of traffic on it doesn't matter - it'd still be considered a public road.

But enough discussion about this and cluttering up your thread. If you want to continue, PM me.

 

[dropped99gs]

Since it is low miles and given you sound like you trust the engine, i would get a good turbo setup like hann or garrett and run around 8 PSI. That should show you some improvement

Exactly my reasoning as well. But i'm not made of out money nor do i come from it.
I've always told myself though that i wouldn't turbo a car without internals first... I've seen way too many engines go from boosting stock internals.
But after reading quite a few posts on here where people are running 8psi with no issues w/ fac. internals i'm thinking i just might.

You said highway in the first post. Unless you have your own private highway, then it's a public road. Whether there is a large population or a lot of traffic on it doesn't matter - it'd still be considered a public road.

But enough discussion about this and cluttering up your thread. If you want to continue, PM me.

you're right, i did say highway, i reread my post to make sure i didnt too, so i really feel like a jack ass. my bad, apologies everyone, was not my intentions to promote driving above the speed limit and unsafe driving habits.

 

[Locke]

A good running factory 420a should pull pretty smoothly and easily from 80 to 100. See YouTube.

Toss the wing and subs, raise the vehicle to allow some air to get under it, and fix your motor, then goto your local circle track or something and see how much your top-end improves.

 

[BigBeans]

raise the vehicle to allow some air to get under it

WTF

I would imagine that lowering the car has the effect of reduced frontal area...

 

[91stocker]

OP, from a quick calculation it takes about 35whp to overcome drag in a 3600lb DSM @ 80mph.

By 120mph, it takes 105whp to overcome drag, which is probably all you have, meaning on a flat road with no wind, 120 is about the max you'd ever see if you had all eternity to get there.

As you can see, the faster you go, the less power you have available to accelerate the vehicle, and the number changes very quickly as speeds increase.

WTF

Exactly, WTF

From a wisemen no less. Someones been drinking a little early today. Lowering the car reduces drag.

Lower the car - Lowering the car reduces the effective frontal area, increasing efficiency. Note that this only works up to a certain point. There will be an ideal ride height for each car. According to this article, 2.7" ground clearance is a good minimum height to shoot for. According to Mercedes, "Lowering the ride height at speed results in a 3-percent improvement in drag."