PrecisionH23a

Too many of these threads are popping up. Feel free to add some great info in this thread so we can throw it in the FAQ thread to help our newer members.

Thanks.

darkd1gt

intake header and exhaust
what ever you can afford will do they are basically all the same just make sure its good quality

Daboi630

https://honda-tech.com/zerothread?id=180883
https://honda-tech.com/zerothread?id=683477

but most importantly for the new people
https://honda-tech.com/zerothread?id=689805
https://honda-tech.com/zerosearch

PrecisionH23a

Good links, but I'm looking for stuff more along the lines of simple up grades and power results.

Daboi630

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PrecisionH23a &raquo;</TD></TR><TR><TD CLASS="quote">Good links, but I'm looking for stuff more along the lines of simple up grades and power results.</TD></TR></TABLE>

Power Results = https://honda-tech.com/zerothread?id=691830

Intake - CAI, SRI for top end, Type S for low/mid
Header - Greddy, Mugen, Prospeed, Hytech, SMSP
Exhaust - 2.5"

Paul H22A4

Cold Air Intake or Short Ram Intake
Header
Exhaust
Accessory Pullies
Crank Pulley
Spark Plug Wires
Copper Sparkplugs
Engine Managment, VAFC, Hondata, etc
Remove Balancer Shaft
Hondata Intake Gasket
Intake Manifold
Larger Throttle Body
Cam Gears
Camshafts
Pistons
Coolant Bypass Mod
Disable EGR
Advance the timing
Turbocharger
Supercharger
Remove Power Steering
Turn off the A/C


Don't bother buying a cheap header. They don't make much power.

Revi

I installed:

GReddy Evolution Exaust
DC 4-2-1 Header
AEM CAI
AEM Pulleys
Apex-i VAFC

Tuned i made 181whp. If you want a simple start this is not a bad route. From there on you can move to High-Flow or Test Pipe, Moddify DC Header to 2.5" collector. At this point your pretty much at the end of basic stuff. The only way to go next would be cams, upping compression or force induction. But then your batting with the majors.

98TypeSH

Intakes 101
An intake is an intake is an intake. If you dont want to be hassled by cops, stick with the stock intake arm and get like a apexi power intake filter, really good filter.

If you dont have to deal with cops, go to home depot/Lowes etc. and make one!! Once again the filter is where its at.

Headers 101
It would be wise of you to decide what type of route you are going before purchasing a header. If you are going turbo you need a turbo manifold (DUHH)
If you decide to go N/A, get the best header you can afford. You should only have to buy 1 header ever, so make it a good one!!

Exhausts
Make sure you get something you can handle the noise level of. Dont get some monster exhaust setup, blast out all your neighbors and make your ears bleed just so you can look cool. Cops will hate you forever, and so will every other person within 5 miles. Typically N/A exhaust setups are about 2.5inchs. Turbo is 3.0. When in doubt, i say go with something stealth and that doesnt attract to much attention but performs well.


After these 3 small upgrades or before, i would HIGHLY recommend a good suspension setup. Live within your budget, but remember, you get what you pay for when it comes to car parts. Keep in mind this is your daily driver, so dont kick your own *** with some crazy *** suspension. Hit a pebble and your head hits the roof = BAD. I would also recommend some nice lightweight rims, not only are they sexy, but they actually serve a purpose.

SUB-0 H23

IMPORT TUNER'S - Power Pages: 1995 Honda Prelude SE (auto?)





Baseline Horsepower: 122.1
Baseline Torque: 124.8



PROS
The 1992-'96 Honda Prelude was an exceptional vehicle for its time, but its hefty price tag made it out of reach for most.
And with the 1992-'95 Honda Civic Si at nearly half the price and almost equal performance, often many overlook the Prelude.
However, the Prelude was an exceptional vehicle with an exceptional H-series powerplant.
The same powerplant that helped propel Stephan Papadakis to an eight-second territory in a front-wheel drive, tube-frame Civic.
The non-VTEC H23 engine found in the Prelude Si and SE was the largest displacement four-cylinder that Honda offered.
The great thing about the H23 engine is the amount of torque it produced (156 lb-ft). Honda rated the H23 engine at 160 horsepower at the flywheel.


CONS
As mentioned earlier, the downside of the Prelude was its price tag. As each year passed, the price tag rose and by the time the 1996
model rolled around the price escalated to $30K. Putting another wrench in the whole deal were the cramped quarters of the Prelude.
Although it had four seats, fitting two passengers in the rear was practically impossible.

DYNO NOTES
We were rather skeptical about dynoing a vehicle with such high mileage (240,000 miles) but we were confident in the Honda powerplant.
The Honda ran extremely well and also showed good figures on the dyno.
The Prelude generated 122.1 horsepower and 124.8 lb-ft of torque to the wheels.


DYNO2
AEM cold-air intake
Air temp @ 69 Degrees Fahrenheit
Temperature difference from previous run: +1 degree Fahrenheit

Peak HP . 124.9
Peak TQ. 127.9



2000 to 3500 HP average: 1 to 2 _ 2000 to 3500 TQ average: 2 to 3

3500 to 5500 HP average: 2 to 4 _3500 to 5500 TQ average: 3 to 4

5500 to redline HP average: 4 to 7 _5500 to redline TQ average: 4 to 6

Peak Horsepower: 124.9 Peak Torque: 127.9


PROS
The AEM cold-air intake performed well throughout the entire rpm band but shined at the top-end. Gains as large as seven horsepower
were witnessed on the dyno. Torque gains were also substantial throughout the powerband with gains of five to six lb-ft from 5500 rpm all
the way to redline.

CONS
Installing the AEM system requires the removal of the air box located in the bumper well on the passenger side. Getting to the bolts to remove
the box is not that easy with the cramped space behind the bumper, so you better have small hands. The other choice is to completely remove
the bumper.

PARTS INCLUDE
Aluminum intake piping, four-inch cone filter, misc. rubber hoses, hose clamps, misc. hardware, license plate, stickers and instructions.

TOOLS REQUIRED FOR INSTALL
10- and 12mm sockets, ratchet, extensions, standard and Phillip screwdrivers, needle nose pliers.

DYNO NOTES
By monitoring the coolant and ambient air temperatures, we are able to perform more accurate A and B testing.


DYNO3
Skunk2 Exhaust
Air temp @ 70 Degrees Fahrenheit
Temperature difference from previous run: +1 degree Fahrenheit

Peak HP. 130.2
Peak TQ. 130.4



2000 to 3500 HP average 2 to 4 _2000 to 3500 TQ average 2 to 3

3500 to 5500 HP average 3 to 5 _3500 to 5500 TQ average 4 to 5

5500 to redline HP average 5 to 8 _5500 to redline TQ average 5 to 6

Peak Horsepower 130.2 Peak Torque 130.4


PROS
The Skunk2 exhaust system made the most significant gain of the three products. The H23 is a heavy breather and the stock system
was not up to par with the small diameter piping. With the Skunk2 exhaust system in place the Prelude sang to full song with gains as
high as eight horsepower and six lb-ft of torque.

CONS
The exhaust system is obviously louder than the stock system but the system comes with a silencer to further muffle the sound.

PARTS INCLUDE
Polished stainless steel exhaust system, gaskets, nuts and bolts.

TOOLS REQUIRED FOR INSTALL
14mm sockets, ratchet and three-inch extension.

DYNO NOTES
Prior to removing the exhaust nuts on the system, soak them with WD-40 to prevent stripping. Also make sure the exhaust has cooled off
enough before trying to remove the system.


DYNO4
DC Sports 4-2-1 Header
Air temp @ 76.5 Degrees Fahrenheit
Temperature difference from previous run: 1.5 Degrees Fahrenheit

Peak HP 134.1
Peak TQ 135.2



2000 to 3500 HP average: 2 to 3 2000 to 3500 TQ average: 2 to 3

3500 to 5500 HP average: 2 to 3 3500 to 5500 TQ average: 2 to 3

5500 to redline HP average: 2 to 4 5500 to redline TQ average: 2 to 4

Peak Horsepower:134.1 Peak Torque: 135.2


PROS
DC Sports has found a proven design and incorporated it into the entire Honda line-up. The header gains throughout the powerband with gains
as high as four horsepower and four lb-ft of torque.

CONS
It's hard to think of any drawbacks of installing the DC Sports header. Besides coughing up the money to purchase the unit, we can't see any
negatives.

PARTS INCLUDE
Two-piece ceramic header, misc. gaskets and bolts.

TOOLS REQUIRED FOR INSTALL
12- and 14mm sockets, ratchet, six-inch extension, 12- and 22mm wrenches.

DYNO NOTES
Although replacing the header is a straight R&R affair, the weathered nuts and bolts are prone to stripping. Using a little anti-seize prior to
installation will help prevent further stripping.

Install time: 1hour

Performance Chart

HP Level HP+ _TQ Level TQ+

Baseline 122.1 _124.8

1 AEM Cold-Air Intake 124.9 +2.8 _127.9 +3.1

2 Skunk2 Exhaust 130.2 +5.3 _130.4 +2.5

3 DC Sports 4-2-1 Header 134.1 +3.9 _135.2 +4.8

Final 134.1 +12.0 _135.2 +10.4

PARTS COST

1 AEM Cold-Air Intake $244.48

2 Skunk2 Exhaust $638.00

3 DC Sports Ceramic Header $411.29

MSRP Total $1293.77


NOTE
With all the power the Prelude is generating, the Honda will not be complete without help in the style department. Our tester was equipped
with a set of 18-inch RH Evolution C3 wheels wrapped with 225/40 Fusion gumballs. Closing up the wheel gap is a set of Skunk2 coilover kits.
The Prelude now flaunts style and speed in one complete package.

CONCLUSION
We were surprised at how well the Prelude performed with the bolt-ons. At 6200 rpm the Prelude made an additional 19.4 horsepower with
the bolt-ons versus with stock units in place. From all the normally aspirated vehicles we have tested at ImportTuner, we have never seen a
vehicle make as much power as the


I got this info from Import Tuner website http://www.importtuner.com/tec....html




Modified by SUB-0 H23 at 7:16 PM 10/20/2004

Shakes

wrote this a while ago so some of it may be out dated.


First Mods –

Generally speaking the best way to start out modifying your car is to make it breath better. Even the old V8 guys will agree to this. So with breathing we are led to Intake, Header (not headers… there is only one), exhaust, high flow cats and intake manifold.

Intake –

CAI – Cold air intake

Places the filter element in the fender well providing colder intake air temperatures. Generally a CAI will provide for more top end power. There really isn't much of a difference (except price) between the AEM, Injen, iceman or a generic EBAY cold air intake.

SRI – Short ram intake

A short ram intake will place the filter element in the engine bay. You will have more airflow over stock but the gains will not be as significant as a CAI would net. SRI has shown to be better for supercharged applications due to the blower not having to suck as hard to get the air, but you are bringing in hotter IAT (intake air temps) into something that already makes the air extremely hot.

FMI – Front mount intake

This would be what I consider extreme rice. It’s that thing that “looks like an intercooler” but is just an intake. If you want to have the slightest amount of water on the road soak you filter then by all means go for it. The rest of us will be laughing when you hydro lock your engine trying to “look” cool.

Intake manifold

skunk2
AIR (theoldone.com)
EuroR reworked

The others on the market would be ones such as the Venom, golden eagle and some other brands that I cant think of right now. But they are all the big aluminum box style. They are geared towards turbo applications and have shown great increases for that, but poor increases if not losses for N/A.

Header

There are many options for headers available. Everything from Custom to off the shelf dime a dozen stuff. The most common are the DC, greddy, Kamakazi, etc etc.

A header is a great addition to your car. However many feel that the cheaper brands are just a waste of money. I would have to say that when it comes to this subject the old saying is true; “you get what you pay for.” That should explain enough on that. There are many good quality custom headers out there that give gains you could never achieve with the DC or greddy. SMSP, Hytech, Prospeed and Mugen are just a few. But all come with a heafty price tag on them.

Be aware that some headers are designed for FI use and others are designed for N/A use. Ask the dealer what the one you are thinking of is designed for. If it is for FI and you are putting it on a N/A motor, you could potentially lose power!

Exhaust

When it comes to this subject I am not going to be naming off any brands. Every person’s preference of sound is different. The most important thing I would say is for N/A to stick to 2.25”, 60mm and 2.5”. Anything over that would pretty much be overkill. FI (forced induction) setups would want more like a 90mm at the least leading to a 3.5” at the largest.

High Flow cats and test pipes

A high flow cat is an essential part of a complete exhaust system. Why on earth would you want to spend all that money on a header and cat back that are 2.5” yet still have the stock 2” cat?

Universal catalytic converters can be welded into place by any muffler shop, and a test pipe can be bolted right up as well. The important thing is to match it to the collector (where all the piping merges together) on your header and your exhaust piping. Do not worry if you have a 2.25” exhaust and a 2.5” collector, you can get a conversion cat made by an exhaust shop or order one online at certain stores.

A test pipe is just that. It’s a piece of pipe, with two flanges on the ends. You run the risk of throwing a CEL (Check engine light) as well as you will NOT pass emissions or CARB legally. Test pipes are not street legal in any state and are sold “for off road use only”.

That takes care of the first basic modifications for your car. Now that it is breathing better you can move onto bigger and better things. If you so choose to go more in depth to breathing you can also do head work and a throttle body.

More power mods!

Pulleys

Crank Pulley-

It is a great controversy on the H22 as to weather the addition of an aftermarket crank pulley is worth it or not. YES it will give good gains. But the difference between all aftermarket H22 crank pulleys and the stock H22 crank pulley is this. The stock pulley has a rubber gasket in-between the two sections of the crank pulley that acts as a dampener. It has been shown many times that the aftermarket crank pulleys can cause major internal engine damage due to not having that dampener. Here is one article. NTPOG Crank pulley article

Other accessory pulleys are available and will give some small gains. Some people swear by them while others swear against them.

VAFC

VTEC AIR FLOW CONVERTOR

A VAFC will allow you to adjust your air/fuel ratios as well as set your VTEC engagement points.
There are many sites on the net that have settings for it. But do NOT use any of them. Every car is different. The only way to get it right for your car is to properly Dyno tune it. The VAFC is a great tool to have and can be quite fun. But do not let it be the cause of your problems. DYNO DYNO DYNO!!!!

Why would you want to adjust your air/fuel ratios?

Because all Honda DOHC engines run rich. A properly leaned out engine will make good gains and run better (performance wise at least).

That’s all that I can think of now. Its 10 pm and I’m starting to get tired. If anyone would like to add to it please email me and I will add it and give you credit.


-Doug

kb58

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SUB-0 H23 &raquo;</TD></TR><TR><TD CLASS="quote">[B]
With all the power the Prelude is generating, the Honda will not be complete without help in the style department. Our tester was equipped
with a set of 18-inch RH Evolution C3 wheels[/i]</TD></TR></TABLE>

All the power... 12hp?

Those larger wheels and tires very likely cancel out that increase too. So the $1200 only keeps the car from going slower with the larger wheels...

SUB-0 H23

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kb58 &raquo;</TD></TR><TR><TD CLASS="quote">

All the power... 12hp?

Those larger wheels and tires very likely cancel out that increase too. So the $1200 only keeps the car from going slower with the larger wheels... </TD></TR></TABLE>

do you know how to read for more than a couple of sentences?

Paul H22A4

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">VTEC AIR FLOW CONVERTOR</TD></TR></TABLE>

Think its "controller". Prolly a typo.

kb58

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SUB-0 H23 &raquo;</TD></TR><TR><TD CLASS="quote">

do you know how to read for more than a couple of sentences? </TD></TR></TABLE>

My point was that they (the article) went to a lot of effort and expense to get power gains, then threw it away with the big heavy tires. If people follow these power suggestions then put the tires on, they may as well not have bothered - their car will not go any faster. They'd be puzzled why the article got power gains yet on their own car they saw a zero gain as shown by lousy time slips at the track. The article does not mention the effective power loss caused by larger wheels and tires. So apparently I've read more then you.



Modified by kb58 at 6:18 PM 10/23/2004

PR_Prelude

I'm pretty sure it's converter. Since all it's does is convert the MAP signal for the ECU to send more or less gas.

On the topic, I have a CAI(Ebay), a Thermal R&D Cat Back(2.25"), and a tuned VAFC. With that I made 172Whp and 140.4lb-ft. H22's tend to run pretty rich, I easy gained 4whp by just leaning it, and it stayed below 14.0 on the A/F ratio.

PreIudeSI

other than the stuff already listed, i think the one (or two) mods that made my car feel much more fun to drive are CM light flywheel and ACT clutch. The engine revs so much faster. Technically, you aren't adding power but you' are reducing unsprung weight and in doing so, allowing your engine to rev faster getting to horespower faster.

kb58

As referred to above, as much as installing a light flywheel frees up rotational acceleration (making the car faster,) adding larger diameter wheels and tires will slow the car down. Neither add horsepower, but both affect how much power reaches the ground.


Modified by kb58 at 2:32 AM 10/25/2004

94Vtecluder

Nice write up shakes and Sub but I want to correct one thing. It is often mistakingly rumored that CAI will help the top end of the RPM more, and the SRI is more for low end. This isn't true, at low rpms the engine doesn't need to breathe as much and the CAI can provide colder air fast enough. In the top end however the engine needs air much faster so a SRI being shorter obviously does a better job providing more air than a CAI even though it may be somewhat warmer. To put it simple a CAI is more for low range and the SRI is more for high range.

Paul H22A4

^^ Don't they have dynos proving otherwise?

Shakes

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Paul H22A4 &raquo;</TD></TR><TR><TD CLASS="quote">

Think its "controller". Prolly a typo.</TD></TR></TABLE>

no its converter

phil2000

About that Import Tuner article...that's an h23 that baselined at 122 whp?? Is an auto actually that much of a drain on the powertrain? My H23+manual trans dynoed at 140hp/140ft-lbs at a much higher ambient temperature.

tuoniz

Yeah that sounds like a good idea! I'll try that just let me clear my throat.

LudeBoyLeRoy

"We were rather skeptical about dynoing a vehicle with such high mileage (240,000 miles) but we were confident in the Honda powerplant."

240,xxx miles!?!?!?? That engine is OLD....even by Honda standards that might account for low dyno in addition to the slushbox...

tuoniz

LOL wow 240,000 that is pretty old. I've got about 50,000 miles on my motor and i'm starting to save for rebuild.

LuDe_GiRl

Hey !!