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Discussion Starter · #1 ·
This is very important for all of you interested in modding your H22 motors! Let me describe the two H22a motors first:

motor 1: JDM H22a with 11.5:1 compression, aem cai, dc header, apex ws exhaust, b&m fpr, dyno tuning for fuel pressure and ignition timing.

motor 2: USDM H22a4 with type-s cams, skunk 2 cam gears, Field VTEC controller, AEM tru-time 3 pc. pulley set, Iceman CAI, HP racing header, Nakayama muffler with 2.5" piping, dyno tuning for cam gears, and vtec controller.

Ok, now stop and think about who should win this test. Motor 2 right? After all, it has way more mods. Well, at least that's what I thought. Check out the results, the first numbers are motor 1's hp/tq, the second numbers are motor 2's hp/tq, the 3rd set of numbers are the difference between motor 1 and 2 (i.e. motor 1 - motor 2):

4k rpm - 104/137, 93/123, +11/+14
4.5k rpm - 115/134, 103/123, +12/+11
5k rpm - 135/140, 105/120, +30/+20
5.5k rpm - 155/147, 137/125, +18/+22
6k rpm - 165.9/145.2, 156/129, +9.9/+16.2
6.5k rpm - 174.5/141, 168/135, +6.5/+6
7k rpm - 176/132, 174.4/130, +1.6/+2
7.4k rpm - 171/122, 170/119, +1/+3

It's pretty obvious that motor 1 here is beating motor 2, even though the 2 motors have similar peak hp numbers. Using the above data points, motor 1 averages 11.25 or so more hp across the rev range, and 11.775 more torque.

Motor 1's data is from my dyno chart.
Motor 2's data is from the following link: http://www.geocities.com/timn_1/type_S_Cams2.html

Hope you guys found this interesting, it sure took me a long time to do the math. Hope you guys appreciate the info
 
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<font face="Verdana, Arial" size="2">Originally posted by LudesLudesLudes:
This is very important for all of you interested in modding your H22 motors! Let me describe the two H22a motors first:

motor 1: JDM H22a with 11.5:1 compression, aem cai, dc header, apex ws exhaust, b&m fpr, dyno tuning for fuel pressure and ignition timing.

motor 2: USDM H22a4 with type-s cams, skunk 2 cam gears, Field VTEC controller, AEM tru-time 3 pc. pulley set, Iceman CAI, HP racing header, Nakayama muffler with 2.5" piping, dyno tuning for cam gears, and vtec controller.
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Were these done on the same day, on the same dyno?

Anyway, increasing compression will make a noticable difference. About 3% per point of compression, so going from 10:1 to 11.5:1, would be about a 4.5% gain. I would also suspect that the fuel pressure and ignition tuning help quite a bit.

I would suspect that the DC would work better than the HP header.

The 2.5" exhaust might be a tad on the large side for a mildly modified H22.

Did you dial in the cam gears for top end power? If so, you hurt the low end. Conversely, you could dial them in for more low end power.

3 piece pulley set? I thought AEM only made a 2 piece set.

Anyway, all of this is moot if they weren't dynoed on the same day, on the same dyno.

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Billy
North Texas Prelude Owners Group
www.ntpog.org
 

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Discussion Starter · #3 ·
Nope it wasn't the same dyno or the same day, but I don't think that means that the numbers are completely inaccurate. I was just posting the info, so people could get a general idea of where certain mods make power. I just typed this up so people could get an idea of what type of trends are happening. I think it's somewhat accurate if you are looking at trends, because the margin of error between two sae corrected dyno charts shouldn't be much more than 10-15% right? Even if the comparison is off by 15% in favor of the motor with type-s cams, it is still clearly evident that the motor with higher compression is putting out much more area under the curve. Error would impact the absolute accuracy of the numbers, but you can still learn something from the shape of the curves right? For example, remember when you told me that increasing compression will give you more hp across the board? It's pretty clear that that is what's happening here.

LLL
 

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Sorry but when I saw 11.5:1 for the compression ratio I started betting on the JDM motor not the USDM one with more mods.

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Mugen front bumper and sides with a combat rear bumper for sale in NJ....talk to me personally. East coaster highly, HIGHLY preferred.
 

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thats my dyno, and thanks for asking me to use it.

i never listed a 3 pulley piece set.

if you were smart about things you would've seen the HEADER comparison test as well. it shows that the DC headers have a HUGE mid range advantage over my hp racing headers.

good thing i don't have any of that stuff anymore.

Tim
 

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<font face="Verdana, Arial" size="2">Originally posted by Joon525:
Sorry but when I saw 11.5:1 for the compression ratio I started betting on the JDM motor not the USDM one with more mods.

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Me too. The JDM motor you said had timing tuning done which led me to believe it was a OBD1 car or not OBD at all. That helps alot.
 

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um, if you take a look at the before and after the hp headers chart on the page you listed, you'll see that if you just put the stock headers back on his engine they'd be putting out the same numbers.

And am I the only one who thinks both those peak hp numbers are low? motor 2 i'd expect at least 10 more hp...

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Flavour
98 Base, Black
I/H, pulleys, tb, p&p, cams
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JUN flywheel, Mugen clutch
www.hondaprelude.to
 

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Discussion Starter · #10 ·
Tim: Sorry. I thought that you posted that info. so other people could see it and check out your results. I'll stop assuming that webpages on the net are open to the general public from now on. I'll make sure to ask permission beforehand every time I visit a website. Also, the fact that both cars have a different header, does not explain the gap in midrange, and most of the high end. I think that has more to do with the higher compression than a difference with regard to a header. I'm sure the header plays a part, but not as much as the higher compression. I would suspect that the hp/tq advantage would apply to the low end also. Too bad I don't have any results below 3750 rpm.

71dsp: Looks like you're right about the pulleys - 2 pieces instead of 3. I'm just guessing that he has 2 pulleys because it says "pullies [sic]" on his webpage.
 

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Discussion Starter · #11 ·
<font face="Verdana, Arial" size="2">Originally posted by Flavour:
And am I the only one who thinks both those peak hp numbers are low? motor 2 i'd expect at least 10 more hp...

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I think that you are right about that - NGLuder also thought that his dyno chart ran somewhat low. I think that he is making more than 154.7 whp.
 

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<font face="Verdana, Arial" size="2">Originally posted by LudesLudesLudes:
Tim: Sorry. I thought that you posted that info. so other people could see it and check out your results. I'll stop assuming that webpages on the net are open to the general public from now on. I'll make sure to ask permission beforehand every time I visit a website. Also, the fact that both cars have a different header, does not explain the gap in midrange, and most of the high end. I think that has more to do with the higher compression than a difference with regard to a header. I'm sure the header plays a part, but not as much as the higher compression. I would suspect that the hp/tq advantage would apply to the low end also. Too bad I don't have any results below 3750 rpm.

71dsp: Looks like you're right about the pulleys - 2 pieces instead of 3. I'm just guessing that he has 2 pulleys because it says "pullies [sic]" on his webpage.

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don't worry about it.

no doubt that the lower rpm torque and hp gains were attibuted to your higher compression and jdm ecu.
 

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Is your JDM H22A equipped with Type S pistons and thinner head gasket? What makes the compression so high compare to USDM H22A??
 
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