Advice for more bottom end.

[jbreitz]

After some mods to my 92 2.3l, the power is great but all the low end torque is gone. what can i do to fix this?

Here's what im running:

I just got done with a new custom fab exhaust you can see in the corner of the bed. (see pic). Its got a pretty big glasspack in the larger section of the stack, other than that its a stock diameter tubing and manifold.

On the other end of the engine i rerouted the existing intake tubing to a obnoxiously overkill cone filter bolted to the stock maf sitting on the battery tray. (other pic)

what would you do?

 

[killj0y]

Bigger exhaust can possibly lead to weaker low end if i remember correctly. Something to do with the scavenging effect. Anyways headers would probably make the biggest difference with that application. I would love to put a snorkel and a similar exhaust as yours but i actually want to have a toolbox lol.

 

[scotts90ranger]

a header doesn't really do anything on these things...

Better low end? put a different rear axle in it (cheaper than regearing) that has better gearing, many base model 2.3 rangers had 3.08's... that's going to be your best bang for the buck

 

[Mark_88]

If you were in Canada I'd let you try my adjustable cam timing gear...only $75 for a new one...it's for adjusting the timing up or down a notch and supposedly gives you more top or bottom end...I've played around with it a bit but gave up on it in order to just get it running...

Other than that...I'd go with Scotts90ranger's suggestion...4:10 or 4:56 gears will give you some punch off the line...

 

[killj0y]

Yea kinda seems like the best option really.

 

[jbreitz]

Thanks guys!

the axle swap would certainly do the job, but fuel mileage is important.

I really just dont have the time to mess with the timing, but i will certainly mess with the exhaust some more. it's hard to explain, but the way i designed it will let me change the piping size enough to help a bit. ill give that a go and let you guys know how it tuned out!

 

[Bryan22]

4.10 geared axle would be great, fuel mileage would probably even go up, and for sure see a change in power, what gears are in it now?

 

[Ranger Sport Honduras]

+1 on gears.
4.10 gears will deffenetly wake that thing up

 

[jbreitz]

ive got 3.45 gears in it now, but i really dont see how higher gears would translate to better mileage. more power, maybe. correct me if i'm wrong, but this seems as though it would almost certainly be at the expense of fuel mileage.

 

[Mark_88]

It would affect the top end more than anything...unless you put on bigger tires and lift it the mileage should be about the same...I've got 3.73 gears in mine and (since I've tuned the carb a bit) get pretty good mileage...about 23 mpg...or 10 litres per 100 km...

The gears don't actually affect engine performance or power...as you probably know...but they get you moving faster than lower gears so, as someone said, you might even see a slight improvement in gas mileage...

 

[Rackster]

4.10 gears with automatic tranny

I have 4.10 gears in my 2000 Ranger. It's all stock and doggish off the line, but runs pretty smoothly on the highway. Off the line, 0-60 mph in 13-14 seconds. I couldn't tell you how fast it will go, but at highway speeds of 60-75 mph, she is pretty smooth and efficient. At around 60, I get about 27-28 mpg, 65 and up I start dropping 2-5 mpgs (with AC on 25-50% of the time).

I've read that increasing the size of the exhaust pipe (e.g. 2.5") will likely kill your low end torque as Killjoy pointed out (I caught a link here at TRS to a guy who builds performance 2.3L engines - read the section on Exhaust). While the aim is to improve the flow of the exhaust gases, a common error is the reduction of backflow to the extent that you actually lose power and in some cases, cause engine damage. Finding the balance I suppose is the key: improve flow without creating harmful situations.

I'm by no means an expert; just someone who reads a lot. That said, I might have a good deal of theory, but not a great deal on practical application of it and a novice by that standard. Take what I've posted here as additional input to your diagnosis.

 

[Ranger SVO]

ive got 3.45 gears in it now, but i really dont see how higher gears would translate to better mileage. more power, maybe. correct me if i'm wrong, but this seems as though it would almost certainly be at the expense of fuel mileage.

I replaced my 3.45 rear with a 3.73 rear back in 96. Not really a big change, but both MPG and drivability improved.

I've read that increasing the size of the exhaust pipe (e.g. 2.5") will likely kill your low end torque as Killjoy pointed out (I caught a link here at TRS to a guy who builds performance 2.3L engines - read the section on Exhaust). While the aim is to improve the flow of the exhaust gases, a common error is the reduction of backflow to the extent that you actually lose power and in some cases, cause engine damage. Finding the balance I suppose is the key: improve flow without creating harmful situations.

I agree, too big could be bad
My exhaust is a 2-1/2-inch after the Cat and I have no problems. So I'm gonna assume up to 2-1/2-inch is OK

 

[Rackster]

Size matters

One thing I began to notice once folks started tuning their 4 cylinder vehicles was that many ran quickly to the fancy sounding exhaust systems. I guess it was becoming the rage sometime in the 90s. Loud cars without any punch. And, many had greasy black smudges forming on their bumpers where the exhaust exited from the vehicles. Standing near one of these vehicles, you could hear the engines 'ticking away' and as they pulled away, blue and black smoke coming out the backside. It got me thinking, so I asked a few friends what the effect of these exhaust stytems; valve lash was a predominant response. So, my aim now is not to become a casualty like that and...let my neighbors sleep as I pull away in the morning. One neighbor has an Impreza stationwagon with a loud exhaust - and that's more than enough.

 

[jbreitz]

Ideally i'd like to get my low end back, but not at the expense of top speed, which is downright pathetic as it stands currently.

ill modify the insert in the glasspack to keep the overall diameter of the tubing down. ill take some pictures to show you guys what i mean.

i also mounted the air inlet temp sensor in a better position, which some research suggested could be the culprit. haven't tested, but that should help a bit.

as a last resort, ill swap a posi-equipped explorer axle in with the new gears, which i've been considering doing for a while.

thanks for the help!

 

[scotts90ranger]

One thing I began to notice once folks started tuning their 4 cylinder vehicles was that many ran quickly to the fancy sounding exhaust systems. I guess it was becoming the rage sometime in the 90s. Loud cars without any punch. And, many had greasy black smudges forming on their bumpers where the exhaust exited from the vehicles. Standing near one of these vehicles, you could hear the engines 'ticking away' and as they pulled away, blue and black smoke coming out the backside. It got me thinking, so I asked a few friends what the effect of these exhaust stytems; valve lash was a predominant response. So, my aim now is not to become a casualty like that and...let my neighbors sleep as I pull away in the morning. One neighbor has an Impreza stationwagon with a loud exhaust - and that's more than enough.

the black on the bumper is from not running a catalyst (which isn't going to get you anything on something smaller than a big block), not from running too large of exhaust... I haven't figured out why all of the honda's have the oil cloud behind them.