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Discussion Starter #1
First time running my car on a dyno...mods as follows:

h22a4 131K KM's on motor
3" exhaust with a magnaflow cat
chipped p28 with a basemap from Advanced Ignition
PLM Header
K&N Drop in filter
Recently changed the spark plugs (NGK V-Power) , PCV valve and o2 sensor.

Results are 160whp/122tq on a Mustang Dyno.

 

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Those numbers are.not.so great.
 

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Discussion Starter #3
I'm slightly disappointed, considering the mods I have. Was hoping for 180whp. But considering its aa mustang dyno and an h22a4...
 

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Opinionated Bastard
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Huh... did you get it tuned, or just run it on the basemap? A tune would be a huge benefit, because those numbers are really low.

For reference, I made 170hp & 134lbs/ft. with my car 4 years ago, and that's with 170k miles on it and similar mods. (3" short ram intake, 3" full exhaust, Hytech replica header, and a VAFC-II).
 

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Just running a basemap. I'm going to do a compression test this winter and a few other things while its stored.
 

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Huh... did you get it tuned, or just run it on the basemap? A tune would be a huge benefit, because those numbers are really low.

For reference, I made 170hp & 134lbs/ft. with my car 4 years ago, and that's with 170k miles on it and similar mods. (3" short ram intake, 3" full exhaust, Hytech replica header, and a VAFC-II).
What type of dyno was that on?
 

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Those numbers are lower than expected. Mustang dyno's read low if they are not corrected properly.

One thing I have seen a lot of is people running to large of an exhaust system on Preludes. A 3" system is great if you have the exhaust pressures from a turbo set-up or a highly tuned NA set-up, but I/H/E you don't have the flow so you get strange back-pressures. If you went down to a 2.5" you would see higher numbers for sure.
Also, a proper tune as you are flowing exhaust gases much faster than expected causing less back pressure and turbulence when the exhaust gases are leaving the cylinder.
 

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Discussion Starter #8
Those numbers are lower than expected. Mustang dyno's read low if they are not corrected properly.

One thing I have seen a lot of is people running to large of an exhaust system on Preludes. A 3" system is great if you have the exhaust pressures from a turbo set-up or a highly tuned NA set-up, but I/H/E you don't have the flow so you get strange back-pressures. If you went down to a 2.5" you would see higher numbers for sure.
Also, a proper tune as you are flowing exhaust gases much faster than expected causing less back pressure and turbulence when the exhaust gases are leaving the cylinder.
The 3" vs 2.5" debate is still ongoing .
 

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The 3" vs 2.5" debate is still ongoing .
You can compensate for this using timing if you want to use a 3". I've personally done both on 3 different 5th gens and seen the results of each. It can work, but its much easier to run a 2.5" on a mild built 5th gen. You will see better gains easier with a 2.5".

I will see if I can dig up my dyno sheets from my experimenting with this. Done both on a 98 base with I/H/E. Nothing changed but the exhaust on a base map and there was a drop from switching to the 3" compared to the 2.5"

I tried the same with my 97 base with a greddy kit. At lower RPM the 2.5" was more efficient but the 3" flowed far better everywhere else so I ran a 3" on that.

On my current 00 SH I am running a 2.5" and will be going to a 3" once the second motor I have is done. Going for high hp NA build this time around.

If you ever switch over to Hondata I can shoot you over some maps to check out with the setups I used.
 

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You can compensate for this using timing if you want to use a 3". I've personally done both on 3 different 5th gens and seen the results of each. It can work, but its much easier to run a 2.5" on a mild built 5th gen. You will see better gains easier with a 2.5".

I will see if I can dig up my dyno sheets from my experimenting with this. Done both on a 98 base with I/H/E. Nothing changed but the exhaust on a base map and there was a drop from switching to the 3" compared to the 2.5"

I tried the same with my 97 base with a greddy kit. At lower RPM the 2.5" was more efficient but the 3" flowed far better everywhere else so I ran a 3" on that.

On my current 00 SH I am running a 2.5" and will be going to a 3" once the second motor I have is done. Going for high hp NA build this time around.

If you ever switch over to Hondata I can shoot you over some maps to check out with the setups I used.
Interesting data. I'll definitely take you up on the offer if I do ever go Hondata!

I'm at a crossroads as to what to do next. I think if I were to spend more money on the lude I'd have to go turbo, but that's a whole new can of worms.
 

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Interesting data. I'll definitely take you up on the offer if I do ever go Hondata!

I'm at a crossroads as to what to do next. I think if I were to spend more money on the lude I'd have to go turbo, but that's a whole new can of worms.
There is a lot you can do to get power out of them. NA is the route I'm going this time around. After spending 25k on the my past prelude turbo build I'm looking to do something a little milder :p

You can do a number of things on the NA side to get more power but that same amount of time and money can gain you larger numbers if you go FI.

You may also want to call the shop that did your dyno and ask them what there correction factors are on the runs you did. There is often a setting they can use that will give correction to what the average dynojet would put out.

If thats the base correction on there mustang dyno they tend to read 5-7% lower than a dynojet with its base corrections. If that's the case you could be looking more like 174-177whp and 128-130lb-ft if its corrected properly. Which sounds about right.
 

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'01 Milano Red - BB615
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You'll see gains with 3-inch on I/H/E, but the difference doesn't necessarily outweigh the loudness, haha:

 

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Discussion Starter #13
There is a lot you can do to get power out of them. NA is the route I'm going this time around. After spending 25k on the my past prelude turbo build I'm looking to do something a little milder :p

You can do a number of things on the NA side to get more power but that same amount of time and money can gain you larger numbers if you go FI.

You may also want to call the shop that did your dyno and ask them what there correction factors are on the runs you did. There is often a setting they can use that will give correction to what the average dynojet would put out.

If thats the base correction on there mustang dyno they tend to read 5-7% lower than a dynojet with its base corrections. If that's the case you could be looking more like 174-177whp and 128-130lb-ft if its corrected properly. Which sounds about right.
They did say those were the corrected numbers, for humidity, etc etc.
 

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'01 Milano Red - BB615
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What type of dyno was this on? Those are impressive numbers!
That's about what you should make with I/H/E and a tune on a Dynapack.

I believe SpeedyFacotry uses a dynojet.
They use a Dynapack which reads about 8-10% higher than a Dynojet. So on a Dynojet my old H22A4 would have made about 179whp and 144whp. Not bad for high mileage and I/H/E mods.
 

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Opinionated Bastard
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Just running a basemap. I'm going to do a compression test this winter and a few other things while its stored.
Get that thing tuned! That's where a lot of your power is hiding. H22's run really rich from the factory, and with a 'safe' basemap, there is all kinds of room for improvement.
What type of dyno was that on?
It was on a Dynojet.
TOne thing I have seen a lot of is people running to large of an exhaust system on Preludes. A 3" system is great if you have the exhaust pressures from a turbo set-up or a highly tuned NA set-up, but I/H/E you don't have the flow so you get strange back-pressures. If you went down to a 2.5" you would see higher numbers for sure.
Eh, I'm going to stop you there and say that you're wrong with that advice. It's been debated a ton of times- H22's love 3" exhausts, and make slightly more power than a 2.5". Not a lot more, but more nonetheless. Saying that he'll gain power by stepping down in exhaust size isn't true, just saying.
 

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Guys, mustang dyno and two roller dynos are less accurate due to drum diameter and weight.

Thats why nascar uses 48" rollers, as they provide the most accurate output.

To "correct" a mustang dyno to read likea dynojet248.would he almost imposwible as one would need to have the calibration weight of the mustang dyno, then the calibration weight of the dynojet so that one could propirtionally calculate the actual numericak output difference. Being that all dynos have unique calibration weights(the data provided in the .ini file provided by the dyno manufacturer, which is uniqe to each dyno), its virtually impossible to accuretly cirrect to dynojet standards.

Lesson: dont be cheap ass and buy or use shitty mustang or dynocom dynos, spend the money and use a reliable NASCAR, F1, WRC, sanctioned device.

....also, mustang dynos usually read higher(due to faster movibg smaller rollers) than dynojets, so if the OP was on mustang dyno then his already shitty numbers would be even shittier.
 
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