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power drag at 80mph, climbs slowly, help!

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I read that you changed the filter's but dose that include the fuel filter? My car sat for almost a year when i was in Afghanistan and when i got back it seamed really dogging like yours is now (from the sounds). I put a new fuel filter and ran some lucas fuel treatment plus I ran the same brand of motor clean to just help get ride of any sludge that may have built up just over time. When I did that little bit of work it ran better and pulled harder. I have the same mods as you but running 18's. I live in southern California and the speed on the high ways are 75-80 most of the time and I never have a hard time dropping down to pass big trucks and getting back up to 80. I hope this helps you and best of luck with the turbo kit that is were you will see the biggest hit in acceleration. :thumb:
 
WTF

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

The only change in frontal area would be from the difference of exposed tire. Frontal area is geometric, and doesn't change because of its altitude.

Frontal area is not the only deciding factor is calculating drag, though it is a very important one. There are other effects which affect the overall drag of a vehicle, such as the toroidal effects of the air passing beneath the vehicle, and the delta of up and downforces.

See Bernoulli, fluid couples, 1st TD, and probably Reyliegh for reference and example.
 
Wow, Give the kid a break you guys! I'm pretty sure everyone started out like that before, Not everyone has the options of taking it to a track, some tracks are about 6-10hrs away, so don't be a bunch of D###'s and help the kid out....

OP first off :nono: You shouldn't even be trying to do 140mph on any hwy that's very stupid and dangerous :ohdamn: Someone or YOU could be gone for that matter.

Now to you question.....I've seen these 420a hit 140mph before how I know...I've had a 95dogde neon r/t and a n/t eclipse with that engine before so I know what that motor can do. Its a lot of work, port out the intake manifold, TB, head, purchase some good headers along with long tube CAI not short ram, these cars jz needs more torque that's what they lag. Now put a Hahn's turbo kit on then you can play with the big boysl.

Happy modifying :D
 
I think there are a few things that need a little clearing up.

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

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..

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.

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

First of all I think everyone should know the difference between "Curb weight", "Gross vehicle weight" and "Gross vehicle weight RATING"

Curb weight is the actual weight of the vehicle with out any additional items (people/crap).

Gross vehicle weight is the manufacturers guessed weight with average passengers and cargo.

Gross vehicle weight RATING is the manufacturers specified "safe" maximum weight that this vehicle can carry including the weight of the vehicle. Now vehicles can exceed this rating, however, the manufacturer states the it is not safe because various parts of the car are not rated for more than that weight such as the breaks and suspension. 3600lbs is this cars rating. If you exceed this it is possible to get a ticket.

What is "curb weight" versus "gross vehicle weight" and do they affect a car? - What Should I Know About Weight? - Epinions.com

I don't know the exact weight but I think the GS is around the 2800 curb weight with the RS being a little lighter and the gst being a little heavier and the gsx weighing the most.


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 LOL

There are no speed governors on the NT models... being just over 100hp is handicap enough.

Wow, Give the kid a break you guys! I'm pretty sure everyone started out like that before, Not everyone has the options of taking it to a track, some tracks are about 6-10hrs away, so don't be a bunch of D###'s and help the kid out....

OP first off :nono: You shouldn't even be trying to do 140mph on any hwy that's very stupid and dangerous :ohdamn: Someone or YOU could be gone for that matter.

Also no :ohdamn: Props for saying that he shouldn't do 140mph, however, racing on public roads and exceeding speed limits is something this forum does not take lightly! This post is a dangerous post! Unless you make it perfectly clear that this is on a closed course and folowing some form of racing rules (most say speeds of 120mph would require a roll cage and other safty mods) you are encouraging others to be stupid. For example... I read this post and think "man... I want to help this guy. I know I will video my car going form 80mph to 120mp and post it so he can see!" Then I go to my nearest highway with my video camera, lose control, and kill a family of four. Its one thing to endanger your own life, however, other people are killed every year because of senarios just like this. Thats why the rules are sooo strict on this please don't second guess the greater powers.
 
I think there are a few things that need a little clearing up.











First of all I think everyone should know the difference between "Curb weight", "Gross vehicle weight" and "Gross vehicle weight RATING"

Curb weight is the actual weight of the vehicle with out any additional items (people/crap).

Gross vehicle weight is the manufacturers guessed weight with average passengers and cargo.

Gross vehicle weight RATING is the manufacturers specified "safe" maximum weight that this vehicle can carry including the weight of the vehicle. Now vehicles can exceed this rating, however, the manufacturer states the it is not safe because various parts of the car are not rated for more than that weight such as the breaks and suspension. 3600lbs is this cars rating. If you exceed this it is possible to get a ticket.

What is "curb weight" versus "gross vehicle weight" and do they affect a car? - What Should I Know About Weight? - Epinions.com

I don't know the exact weight but I think the GS is around the 2800 curb weight with the RS being a little lighter and the gst being a little heavier and the gsx weighing the most.




There are no speed governors on the NT models... being just over 100hp is handicap enough.



Also no :ohdamn: Props for saying that he shouldn't do 140mph, however, racing on public roads and exceeding speed limits is something this forum does not take lightly! This post is a dangerous post! Unless you make it perfectly clear that this is on a closed course and folowing some form of racing rules (most say speeds of 120mph would require a roll cage and other safty mods) you are encouraging others to be stupid. For example... I read this post and think "man... I want to help this guy. I know I will video my car going form 80mph to 120mp and post it so he can see!" Then I go to my nearest highway with my video camera, lose control, and kill a family of four. Its one thing to endanger your own life, however, other people are killed every year because of senarios just like this. Thats why the rules are sooo strict on this please don't second guess the greater powers.


Noob to the forum and kinda blew it initially talking about running my car on the highway. If I could rent track time every day i would, wouldnt be much of an argument to say that we all would.

As for the focus of my issue, not being speed but rather my car running well.

I did change my fuel filter along with running lucas octane boost/ injector cleaner. I did not run anything through the engine however to break up possible sludge so tomorrow I will be making a trip to pick something up.

I do have a long tube cai, its not injen or anything but i like it and its built well enough.

As for the ride height, spoiler, and/or weight affecting the drag - I have spoken with some fellow car guys, one a previous gst owner, and if it is a drag issue we came to the agreement that air is having trouble coming from under/behind the car. The previous gst owner suggested a skid plate(s) type of application under the engine bay to help move air more fluidly under the car.

I do not think it is a weight related issue or the spoiler playing a part.

My car runs amazing - responsive throttle, no missing or sputter, engine is smooth - no pings or clanking, and she isnt burning oil. I've checked other areas and didn't find anything. Spark plugs appeared normal.

One thing though that is getting to me, on the intake located along the lower part of the cai there was a male end to connect some kind of vacuum or possibly sensor. The original owner never plugged or capped this nozzle.

I removed the intake, TB, and took a look inside. Was not pretty. There WAS gunk along the intake, TB was nasty looking, and the intake manifold is begging to be removed and cleaned. I did clean the TB about 80%. The butterfly operates smoothly opening and closing.

I plan on picking up a gasket tomorrow and this weekend taking the intake man. off and along with the TB give them one heck of a cleaning.


I kicked myself pretty hard today because after pricing some initial turbos and kits I could have went turbo during my overhaul of my car easily with the budget I had. Rather my focus was reliability and longevity instead of performance.

OH and for all of you bad mouthing about my talk about speeding on the highway and saying i'm the kind of person that causes wrecks, yea, dont be mad because of your ATTEMPT to show off in a car that resulted in some kind of epic failure.
 
Edit: so I bought some ZMAX and wow, must say i was impressed within the first mile at how much smoother my engine revved up and down.

Dropped it to 3rd to pass around a car and wow, pulled hard all the way through and when I shifted to fourth rather than the car losing pull she started pulling hard.
I have no doubt that there was some extra friction and build up. ZMAX is definitely worth the $20 from now on whenever i change my oil.
Next oil change is soon and I am anxious to see how it comes out.

After reading other threads on here about removing the intake manifold it seems as though I'm going to have a field day with that. Took a look and felt around, I feel confident I can do it once i get everything out of the way.

Debating on just ordering an after market Intake Man. and fuel rail while I'm taking it all apart. I don't like to do things twice. The only things I'm lacking for a full exhaust is headers and a high flow cat/ test pipe. I have a custom 2 1/2" cat back already and it sounds deep and mean. Lots of compliments on how deep my exhaust it rather than raspy and whiny like about 90% of the other cars I see on the highway. But again I dont want to spend money on headers and what not when ill be replacing them with a turbo manifold in the future.
Which is why i may consider a set of Ebay headers or try to find a good deal so when I do turbo i don't feel too big of a kick in the nutz.

I had my car inspected barely 2 weeks ago and everything computer wise checked out that the engine is running proper. But after today and thanks to ZMAX I now am totally confident in my car. That bug telling me to keep looking for things to fix or check to make sure, just in case, has finally moved on.

Immediate plans - a few ( 3 ) door dings I would like to pop out - I removed the spoiler and I must say I was really turned on by how the 2g looks with no spoiler. Will be looking for a proper and stylish way to plug the holes and remove spoiler for a while to give the car a new look. Rear window needs new tint. Drivers side seat needs to be stitched up on one seam.

I've already installed a full system. minus amp for components.
Kenwood Xcelon Deck - 2011 model like 3rd from the top of the list
Kenwood Xcelon 6 1/2" door and rear coaxial and off brand tweets in the dash.
I can crank it all the way up and distortion is almost non existent. Turn down one level from max and no distortion at all. Almost makes me not want to get another amp.
In the back - 2 Alpine Type R 1042D 10" subs in a ported black carpeted box
Powered by Rockford p800.4 which i have some how managed to get an estimated 400 watts over what the highest rated rms is. Supposed to one run each bridged channel at 4ohms but i'm running both at 2ohms and the amp barely get warm. I started at 8 ohms, then 4 ohms, and tested 2 ohm with just one bridged channel and booom said the bass. I need a bigger box and an amp with twice the power to really let these subs bang but i'm satisfied.

If I get bored enough tomorrow and anyone on here cars enough I will post pics.


Thank you everyone for your help and Junk, ty for suggesting some sludge cleaner/ engine lubricant. Like I said, I had thought about it but discarded the idea.


There is a new track that recently opened and is supposed to be one heck of a road course. I believe the 5th of next month they are having an open event day where you bring your car to the track. It's a $150 registration fee plus your car has to pass track inspection. Also by the end of the year they should have a full race shop built to facilitate the needs of the best world class race teams to the every day tuner. :pray: TY
 
You'll be wasting your money if you buy an intake manifold, stick with the stock. Any intake manifold you buy will probably be bigger then the stock and that's a no no when you're running a non-turbo DSM.

Your air filter will take in as much air as it can but once it reaches your intake manifold, it'll take a longer time for the air to be sucked into the exhaust. You'll have no restriction in your intake manifold, it'll be like a loose asshole. Pressure... is good. Goodluck
 
You'll be wasting your money if you buy an intake manifold, stick with the stock. Any intake manifold you buy will probably be bigger then the stock and that's a no no when you're running a non-turbo DSM.

Your air filter will take in as much air as it can but once it reaches your intake manifold, it'll take a longer time for the air to be sucked into the exhaust. You'll have no restriction in your intake manifold, it'll be like a loose asshole. Pressure... is good. Goodluck

Haha I got ya. I just found out I will be coming into some more money soon, and I should have enough to go Turbo. Or at least get all the parts together. Talking to a family friend who drags proffesionally about helping me out one weekend and let me use his shop and knowledge.

But like I said before, even though I have faith on my engine being solid, I prefer and feel it will be best overall do to internals before adding boost.


I know it is good to have a HP goal. Since its my DD Im not aiming for anything crazy.

End result I wouldn't mind 260hp at the wheels. Rather than ask here ill do my research in the other threads.

But any suggestions and recommendations are welcome. My total parts budget - around 2,000 over the next few months is what I have coming in. So internals may be ordered first. Then work on the Turbo and essentials. Now its time for me do more research on here.
 
260whp is a pretty stout goal with 2k, considering you started at about 100whp. The bottom end build will run you all of your 2k budget. To get the most of your budget id think getting your turbo set up now and running 8psi on stock motor would show the best gains. Maybe 200hp at the crank. Add some tuning to finish off your budget.

In all honestly though for 2k you can get a super clean 1g gsx and have the same performance stock, with the addition of awd. Keep your n/t for a nice dd and mod the gsx.
 
260whp with max boost. would like to drive around with maybe 210-220whp.



2k is not my final budget. Just my initial. I'm going to start a parts lists and order accordingly. Get what I can now and once I get some more extra cash finish up the list.

I'm thinking of going ahead and ordering the internals. Send off the block and head to be taken care of, bore .20 over. Basically built to handle more hp than i want to drive around with. Decent turbo pushing about 14-16psi and call it done.

I know people who build engines and I'm hoping i can get a deal on getting everything done as far as machine work and what not.


Estimated time frame from now till completeion - 6 months i should have all the parts and get engine worked over.
 
Sounds like you have a solid plan and are stuck with the 420a build. Wish you luck and hope you change your mind and go with a 4g before you spend 10k for 12's.
 
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 say bs to this since they were governed to 120 or 125 I believe in that year.
 
I say bs to this since they were governed to 120 or 125 I believe in that year.

I was second owner. Everything appeared stock. I went fully built n/a. Would wrap past the 140 easy.
This was on an airstrip. But my 2000 civic si would fly. Sold when i got out of the navy.

I mean if I come across a 2g gst or gsx locally for a good price ill sell my gs and use. Extra funds on top to get one. Till then I feel if I build my engine right ill be ok with HP I'm wanting.

Sounds like you have a solid plan and are stuck with the 420a build. Wish you luck and hope you change your mind and go with a 4g before you spend 10k for 12's.

I would rather run Autox or road courses.
 
So I've been on here doing countless hours of research for the overhaul of my car. I want to thank everyone who chimed in with advice, and apologize for the appearence I condone street racing/poor public road driving.

Anyways, the reason for the update is I'm trying to figure out a few things I can do to improve my cars current performance. Since purchasing the car I have Went front to back replacing and flushing anything that needed to be done.

List so far -

Fuel Filter
NGK iridium ix plugs
Accell Wires
New ignition coil
Valve Cover Gasket
Full Long 2 piece CAI w/ Spectre filter
Water Pump
B&M Edge short throw shifter
Gates timing belt kit - both pullies
Tensioner
Gates serpintine and accessory belts
2 1/2" Cat back to Tsudo fireball muffler (clean deep sound)
Tein springs kyb? struts
New stereo /w subs and speakers
Fully synthetic Oil
New oil pan and gasket (prev. owner somehow managed to slam it due to cars ride height.)

Modestly cheap additoins I would like to make in the new future -

Headers
high flow or delete cat
Colder temp thermostat


I know cams should be on that list but I can't budget that right now. What I'm hoping to obtain is other ideas those with the 420a have done and can recommend that would help my car run better all the way around. Thanks ahead of time.
 
Headers,
Downpipe w/o CAT,
Underdrive Crank Pulley
Polyurethane Motor Mount Inserts

Lightweight Flywheel
 
Does a udp. Really make a difference? If so who makes a better one? Would like to try that. I've read about them but would like some good honest feedback from personal experience.

Something else I would like to find would be upper sway bars front and rear, possibly lowers too.
 
Does a udp. Really make a difference? If so who makes a better one? Would like to try that. I've read about them but would like some good honest feedback from personal experience.

Something else I would like to find would be upper sway bars front and rear, possibly lowers too.

Yes it does and they don't make a "better one" they just make one that is a smaller diameter and a little lighter. Ebay ones are usually fine. Ebay works well with a lot of those sway bars too.
 
I will be on the market for one then. Money doesn't fall off of trees for me but I don't like going to the cheap route either. I'm a firm believer you get what you pay for. This week I'm going to be fabricating a new box for my subs. The one I have now works well but is not big enough. Going to look at ideas other people have come up with and hope that in the end I will still have hatch space. What I have in mind will take up just about all the room in the back.
 
So today I jacked up and squeezed my way under my dsm to remove and gut the cat. Removal was easy and so was gutting it. Use a post driver and extra steel bar laying around it wasn't much trouble at all. The mesh was a little bit of a pain but did come out. Reinstalled and took her for a test drive.

What I noticed wasn't much at take off. But when I shifted from 1st to 2nd there was a noticble gain, and again from 2nd to 3rd upon clutch release I noticed more torque. As far as sound goes there is not much difference if any honestly. It's hard to tell b/c my intake is so loud i can't really hear anything else until throttle release. Before my exhaust was a little throaty and had a slight rumble at the end of decelerating but I didn't notice that sound after gutting the cat. Also NO CEL !!! :pray: Hope it stays off. Just had my car inspected so I'm good for a year. If I have any problems next year I'm sure i can find some small shop to sign off anyway. I know quite a few people who do this. May cost an extra $20 but that's about it.

Total time - 2 hours.
Tools used - air gun and assorted sockets
- ratchet and small socket for hanging bolts and ground bolt.
- Post driver and 2 1/2' 1" steel rod.
- Pliers
Estimated Hp - 4-5hp gain and a few ft. lbs. of torque.

Worth the effort??? Most definitely.

Whats next ??? headers w/ 2 1/2" dp to complete 2 1/2" exhaust into Tsudo fireball muffler.
Clutch line restrictor plate to be removed.
Under drive pulley

Hoping to wrap those up by the end of the month. Throughout the fall I plan on saving for internals and turbo components. I feel confident my car could easily handle 8psi right now w/out breaking a sweat. As i've stated before though I am going to build my engine properly before adding boost. I have been and will continue to read the posts on here about building a 420a for boost. Lots of great information on here and feedback regarding do's and don'ts.

Regardless I'm still on the hunt to save a gst like I did my gs. Hoping to find one that's just been neglected and not driven for some time that just needs a simple overhaul.

Reason for this update was to inform anyone reading this that gutting the cat is not such a bad idea. I'm sure with a stock exhaust and muffler there is a raspy sound. But if you have a cat back on and a better muffler than what i call the coffee can muffler your car will sound nice.

Coffe can muffler = huge oversized muffler hollow inside that sounds like a pissed off bumble bee going down the road. Basically a cheap muffler that came with a silencer. I dont understand why someone would want a louder muffler just to silence it????

Middle price range I recommend what I have or similar. Tsudo Firball . Deep clean sound up and down the rpm range.
 
So it's been about 400 miles since my last post and here's some good news. No CEL since I gutted the cat. Also, the last 100 miles I've noticed a bit more difference when getting on the accelorator.
As for the sound - clean, deep, and throaty at lower rmp's. I have not heard one bit of raspiness.

If anyone is interested in sounds clips, when I get the time I'll post up request.


Using 3M headlight restoration kit today to renew my headlights.
 
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