Well when the last header was test fitted on a 5th gen Prelude (Ref: https://honda-tech.com/zerothread?id=491394) the secondaries were a little too close to the cross member. One of the things I've been trying to incorporate with this header is that no modifications would be required to the cross member. Also, many owners with the 5th gen and ATTS were interested to know if the header would fit their vehicles.

So this is what I came up with. I was able to increase the radius of the 1st bend in the #1 primary, get rid of (2) little bends in tubes #2 and #3 prior to going into the collector, provide more clearance at the cross member and I should be able to make the header work for all the 4th gen, 5th gen and ATTS equiped cars.

The pictures below show the collector used on header #4. The collector will be similar but there will be an extension of the 2-1/2" tubing so that it will clear the P/S cover on the 4th gens and the ATTS unit on the 5th gens.

P/S and A/C can be retained. I'm almost positive that the header should work with any H22s in the Accord since it will clear the cross member and front engine mount in the Preludes. It should also fit in the Civics, the only thing that may need to be verified is the space in front of the engine and the type of radiator used. If someone has pictures of their H22 in the 92-95 or 96-00 Civics with A/C, please send them to me and I'll take some measurements.

As for dyno results, I posted the graph in the referenced thread above for Corey's stock H22A4, with AEM CAI, a lightened flywheel and a race exhaust which included a 18" long resonator, a turn down and my #3 prototype header. Those peak numbers were 185/146. Prototype #3 used cheaper formed collectors where #4 used merge collectors and was set up to have more straight tubing coming off the head prior to turning down. We have not been able to test #4 yet since Corey's tranny is shot but I would expect it to produce better numbers and more importantly a better curve due to the addition of merge collectors and changes in the tubing configuration. With the theorectical improvements detailed above for this 5th prototype header, I could foresee some minor improvements over header #4.

Pictures deleted


Modified by SMSP at 10:49 AM 8/3/2003

 

 

Nice info on some minor gains possible....

Any chance of an email list or newsletter for new SMSP products or forthcoming runs? Or is that sorta planned for the new website to have that info?

Won't be able to make this production run unfortunatly, but am still very interested.

Thanks....

 

Hey Dave, any idea if the header will clear the front engine mout that the H22 equipped 90-93 Accord owners have. What I mean is that this mount comes up a lot higher than the front mount for the Prelude and later accords. I noticed this when I put on your 4-1. The mount hit. In my case I was able to make a significant bend in the bracket that attaches to the block. This bend and the use of a very thin nut allowed for the needed clearance. I realize that the 4-1 was an old design, but I was curious if considerations were made for both styles of engine mounts.

 

Can you post a picture of the mount. I'll post one of the prelude mount on the jig with the header and see if you think it will clear.

 

Is this header only for the 5G? I ask because the 4G H22A1 engine has an engine mount right at the front center of the engine. How are people putting this header on their engine? What am I missing here?

 

It will fit ALL H22 equipped Preludes from 92-on

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kb58 &raquo;</TD></TR><TR><TD CLASS="quote">Is this header only for the 5G? I ask because the 4G H22A1 engine has an engine mount right at the front center of the engine. How are people putting this header on their engine? What am I missing here?</TD></TR></TABLE>

I should be able to make the header work for all the 4th gen, 5th gen and ATTS equiped cars.

 

1994 Civic EX coupe JDM H22A with A/C, PS, cruise, etc etc:



And for measurement:



I'm rooting for you man, if the dyno says these headers are worth it, I'll be buying 2-3 of them.

:-)
Jeff

 

Im want in on this, I wan this header bad, I will have to money in like a month. Please contact me when you get ready for another batch.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeff652 &raquo;</TD></TR><TR><TD CLASS="quote">1994 Civic EX coupe JDM H22A with A/C, PS, cruise, etc etc:

</TD></TR></TABLE>

Well the Civic probably has less room than the Prelude, but we may still be in luck. Hopefully the worse thing would be sliding the A/C fan out of the way for the install. This header comes out far from the header to promote better flow so I'm sure it sticks out more than other headers.

It looks like you may have to remove the heat shield to get the measurement I need . Can you measure from the manifold gasket surface, perpendicular from the head out to the A/C fan? If you could measure from each exhaust port location that would even be better. Thanks a lot in advance.

 

Hi Dave - Gee where'd you get a 5th Gen just lying around to test that header on?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by preylude &raquo;</TD></TR><TR><TD CLASS="quote">Hi Dave - Gee where'd you get a 5th Gen just lying around to test that header on? </TD></TR></TABLE>

I heard it was abandoned and soon we'll be able to apply for a title.

 

Sure, I'd be happy to. I'll try to measure them tomorrow, but probably Tuesday of next week.

:-)
Jeff

 

Well I had to cut the mount on Corey's car also. We're not certain that the mounts are different. But here are some pictures, let me know if you need anything else. Thanks.

"Pictures Deleted"


Modified by SMSP at 10:50 AM 8/3/2003

 

excellent to see so much time and effort being put into this. Have you any idea if it would require any cutting of a 5th gen's front engine mount to clear this header?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GirlNALude &raquo;</TD></TR><TR><TD CLASS="quote">excellent to see so much time and effort being put into this. Have you any idea if it would require any cutting of a 5th gen's front engine mount to clear this header?</TD></TR></TABLE>

No cutting of the front engine mount required for the 4th or 5th gen. The cross member and the front engine mount of the 4th and 5th gen cars are the same. From what I can tell, the only difference between the 4th and 5th gen is the length of the stock A pipe.

 

Thanks for keeping us posted! Did Corey get his new tranny in yet? I'm looking forward to seeing the dynos of the production header...

 

He picked up a used tranny that I think he'll use the synchros from but he's waiting on the LSD. I hope it's done this week so we can dyno or else it won't be until the first week of July. Unless someone else wants to come over with a stock H22. It would be nice if it was in a Civic since the changeover would go quicker, but at this point I'll take any car with the stock engine.

I know that header #3 did better than the first 4-1 which was 1-3/4" x 1-7/8" stepped primaries that I built almost a year ago, so I'm really looking forward to making more power with either prototype #4 or #5.

 

I picked up my tranny, now just waiting on my LSD to return for a rebuild.. Anyways, we are going to do some baseline runs w/ header #3 and then the "production" models, #4 and #5 I believe.. Then, I will have a FPR to do some tuning, and see what we can get out w/ just a little bit of playing w/ the fuel..

 

Good luck playing with the fuel. You'd almost be better off with a set of carbs than a stock P13 ecu. Here is a stock P13 A/F plot using adjustable fuel pressure to try and get parts of the rev band in the right place:



If you are really stuck with a stock ECU, then I guess you have to decide which RPM you use most and tune it for that. Also, I would suggest that you disconnect the O2 sensor. You will get a cel, but at least the ECU won't be trying to correct for whatever you change you make to the fuel pressure. I've also seen people remove the clock fuse, so every time you turn off the car the ECU is reset. A better way to change things is to get into the ecu and change the maps. Here is a A/F plot from a H22 running a P28 ecu with the maps tuned a little:



Sorry to get a little off topic. My point was to say you may have trouble trying to get the results you want with a FPR...

 

ANything I think will help some. When we recorded the 185/148 numbers the A/F was no leaner than 11.8:1 from 4800 up.

 

I can legally use a P72 (OBD1 GSR ECU) to use on the car.. hum...

 

Dave.. Check your IM. thanks.

 

What are the details of the ECU rules? If you can use a stock ecu from a different car, then how is that different than a stock ecu with different maps? If they just don't want you changing rev limits, you can keep the stock rev limits and just tweak the fuel/ignition tables. Just a thought, I don't know the rules you are subject to...