OE Manifold CRACKED!
#21
When I thought the price was $75 shipped the answer was yes. When I found out it is now $100+shipping the answer is no, they only go three blessed millimeters over stock size for petes sake! I had sort of thought that they were doing an extreme porting job, but it turns out not to be the case. I would spend the money if I were going FI, but I'm not. The adhesive I used to re-assemble the manifold is not inspiring a lot of confidence in me. It bonded beautifully and set up solid as stone, but it is VERY flexible (rubbery) and I'm worried it may fail under pressure. So I may let it sit another day and then cut it back apart to be re reglued with Liquid Metal filler. After all it would be a real shame to do all this work only to have the head digest enough cured adhesive to seize the valve train LOL
#22
If you have the money you might invest in this.it's a cheaper one but should do the trick.
PLASTIC WELDER WELDING KIT FAIRING SYNTHETICS PVC ABS : eBay Motors (item 330416021358 end time Mar-27-10 17:08:01 PDT)
PLASTIC WELDER WELDING KIT FAIRING SYNTHETICS PVC ABS : eBay Motors (item 330416021358 end time Mar-27-10 17:08:01 PDT)
#23
Hell, I may get one of those whether I use it for this or not! Thats really cool! The adhesive actually set up better than I had first thought, so I am going to install it as is for a first attempt. I fixed the grind through in the top and sealed the throttle body neck where I had cut through it with the hacksaw yesterday. So the intake is ready for install and maiden voyage as soon as the weather cooperates, hopefully some time early this week (tomorrow is gonna be shitty) I will post some installed pics and my impressions ASAP.
#24
any kind of mods without flow testing before and after is well.....lmfao
brave brave people
does anybody know what kind of education an engineer gets?
even without a formal education, common sense dictates dyno testing before and after (yes i know this costs money but there r thing u just dont ghetto macgyver)
brave brave people
does anybody know what kind of education an engineer gets?
even without a formal education, common sense dictates dyno testing before and after (yes i know this costs money but there r thing u just dont ghetto macgyver)
#26
http://img704.imageshack.us/img704/4...akepics008.jpg
I think i would remove the horrible lip at the throttle body inlet!! It could constrict the airflow!! (Or so i think!)
Marko!
I think i would remove the horrible lip at the throttle body inlet!! It could constrict the airflow!! (Or so i think!)
Marko!
#27
^^I did remove a fair amount of that lip, it is an integral part of the flow equalizer. I was limited by the fact that if you remove too much you go through the wall of the intake though. And Profit, yes I realize I'm no engineer, but thank God you don't have to be one to mod a car! I am trying this because I can, and because I'm modifying a spare intake manifold I can remove it and re-install the unmodified stuff if it doesn't work. What is the worst thing that can happen? Have the guts to try something new every now and then, it will make life more exciting!
#28
Round one goes to the intake, sad to say. I put it on the car this evening and fired it up. It started without hesitation and settled into a normal idle for about a minute, then began to porpoise up and down between about 850 and 1000 RPM. I poked around the TB under the hood and could hear air escaping from the intake near the TB neck where I had made some repairs. So I have a leak somewhere that is causing the ECU to freak out. I will try re-gluing the intake only once, then I'm getting me a plastic welder and we'll do this right! Further updates as events warrant LOL....
#31
Okie Dokie, i discovered the root of my leaking problem. The Liquid Metal Filler I used to repair the TB neck was so hard that it couldn't flex with the rest of the manifold. So as soon as I fired up the engine the filler cracked and the mani leaked around the base of the TB. I have already re-filled the damage with something MUCH more flexible and should be able to try again tomorrow or the next day. And on a side note, I have re-discovered why no one tries too hard to polish the lower intake manifold. There are so many itty bitty voids in the casting that you'll go crazy trying to sand them all out! I have gone from abrasive wheel to sand paper four times and have succeeded in making the smoothest shitty looking lower intake mani of all time I may actually succeed in lightening the damn thing enough to see a performance increase before I get it to look half-way decent
#34
Personally, I think the original Honda design has more to do with creating a false plenum. I think you'll see more losses than you will gains (under the curve, your peak may move either up or down, but my $ says your average power will be less). You've modified the volume of the manifold, your resonance point will be at a different spot in the RPM band.
As you said the Honda engineers are fairly smart. They didn't put it there because they wanted to to decrease power.
Good read if you'd like to study a bit on intake design:
Intake Manifold Tech: Runner Size Calculations - Team Integra
As you said the Honda engineers are fairly smart. They didn't put it there because they wanted to to decrease power.
Good read if you'd like to study a bit on intake design:
Intake Manifold Tech: Runner Size Calculations - Team Integra
#35
Hey man quit peeing in my Wheaties! JFWY, I'm hoping that there will be some change, be it good or bad (hoping for good of course) I just have been wanting to try this out for so long. Watching the threads on truly custom made manifolds and seeing them fall into two camps: The weapon R type, which is basically a Stainless higher volume replica of OE, and the SHG Mike, which seems to eliminate the large "surge tank" in favor of directly feeding each runner from the TB. Since I have neither the money nor the know-how to design my own long runner manifold I figure I'll screw with what I do have and see what happens!
#36
Since I have neither the money nor the know-how to design my own long runner manifold I figure I'll screw with what I do have and see what happens![/QUOTE]
I applaud your tenacity and curiosity..... If your efforts gain an increase in power that satisfies the butt dyno test measurably then you are rewarded..... Power gains that are measurable on a dyno don't always work out all that well when you are behind the wheel in real world driving scenarios unless the power gains are consistent throughout the power band..... Since the manifold is of plastic construction there are plastic products that can be used to refill material that has been removed that created negative results and also added and shaped to increase flow velocity which is what needs to be done to fill the combustion chambers of engines with multiple valves and small ports..... The emphasis for an increase of power on this type of engine is not so much on mass volume but the flow velocity....... Good luck and best wishes for a successful outcome.
I applaud your tenacity and curiosity..... If your efforts gain an increase in power that satisfies the butt dyno test measurably then you are rewarded..... Power gains that are measurable on a dyno don't always work out all that well when you are behind the wheel in real world driving scenarios unless the power gains are consistent throughout the power band..... Since the manifold is of plastic construction there are plastic products that can be used to refill material that has been removed that created negative results and also added and shaped to increase flow velocity which is what needs to be done to fill the combustion chambers of engines with multiple valves and small ports..... The emphasis for an increase of power on this type of engine is not so much on mass volume but the flow velocity....... Good luck and best wishes for a successful outcome.
#37
Props to you for fooling around, I didn't mean to sound like a douche, was just trying to point you in the right direction.
After you get done "improving" your factory manifold, maybe you can design a plenum from the ground up, make the resonant frequency at a different value, and make them and sell them (so lazy guys like me can buy a proven design).
#38
Well the leak fix worked! I put the mani back on this afternoon (about two hours ago) and this time it fired up and settled into a normal idle right away, no porpoise-ing The ECU took a moment to sort out what it was seeing but never hesitated. I went for a twenty minute thrashing to see what I could see (and feel) First impressions 1. Holy hell is it loud! The sound is like going from an OE airbox straight to a short ram, except you've removed the hood first! There is also an exagerrated blow-off valve hiss when you shut the throttle at higher RPM (like when doing a full throttle two three upshift) 2. Mid RPM response seems soggier than before like it is taking longer for the enigine to add RPM could be just my imagination. 3. Full throttle feels stronger, especially when upshifting quickly into second and third, once you get into fourth the effect is blunted somewhat. 4. Did I mention its loud as hell? I'm not sure I like it so loud as I've sort of built my car to be low profile. I now sound like one of those hated "street racer Hondas" whenever I roll into the throttle too heavily. We'll see how she does in daily driving this week, I'll give some better impressions after I've put some miles on it. And in the meantime, I'm carrying the OE manifold and all the needed tools in the cargo box, because i may be crazy, but I'm not stupid! Oh yes, one other word of caution. Be careful with the weld nut fixtures that hold the plastic upper to the aluminum lower manifold. I got a little too enthusiatic re-installing the lower one and torqued the stud right in half! One of the spare TB bolts and a half dozen washers and i was able to replace it (thank God!) My first thought was "man instant karma is a motherf^&*er!" LOL
Last edited by grtpumpkin; 04-03-2010 at 06:32 PM. Reason: forgot someshing
#39
Hey - Roads closed pizza boy! I've been busy with life and missed this thread - great job. Props to you for doing all this work and handling all the little things that can come up when your modifying.
Cat :x
PS You watching the game tonight? Go Mountaineers!
Cat :x
PS You watching the game tonight? Go Mountaineers!