some of you my remember my thread from a while ago about the "homemade intake manifold vs. Edelbrock victor x " https://honda-tech.com/zerothread?id=1559749

well time has come for v.2 and hopefully its better than v.1

here are some pics of the new manifold. I made a few changes from v.1 hopping to improve air vellocity and fuel automization in the lower rpm ranges.

lets see if you guys can make out the differences.

 

well, the plenum is way bigger, thats for sure. thats the only thing i noticed right off the bat. looks friggin sick though!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by I Have an STD &raquo;</TD></TR><TR><TD CLASS="quote">well, the plenum is way bigger, thats for sure. thats the only thing i noticed right off the bat. looks friggin sick though!</TD></TR></TABLE>

you are right, the plenum diameter was raised to 5" instead of the 4" of the v.1

 

Velocity stacks are much higher off the floor of the plenum and the injector bosses are farther upstream. Should work better than V1.0

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nfn15037 &raquo;</TD></TR><TR><TD CLASS="quote">Velocity stacks are much higher off the floor of the plenum and the injector bosses are farther upstream. Should work better than V1.0</TD></TR></TABLE>

you are right also, but there is one more thing about the injector bosses that you have not noticed. you think you can spot it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by onefstek &raquo;</TD></TR><TR><TD CLASS="quote">you are right also, but there is one more thing about the injector bosses that you have not noticed. you think you can spot it? </TD></TR></TABLE>

What that they are on the bottom?

 

Looks good.

 

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

What that they are on the bottom?</TD></TR></TABLE>

thats right, I put them on the bottom of the manifold, so it keeps it clean looking on the top. Just something I wanted to do, I want to try to keep my eng. bay clean looking, as much as I can. But I also know thats hard to do with a turbo car.

 

I beleive it is better to aim the injector at the back of the valve, at least for part throttle, cold start, and emissions reasons.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99_GS-T &raquo;</TD></TR><TR><TD CLASS="quote">I beleive it is better to aim the injector at the back of the valve, at least for part throttle, cold start, and emissions reasons.</TD></TR></TABLE>

Agreed and the bosses should be closer to the flange.... you are going to be spraying the runners and not the back of valves.

I don't think this version is going to be any better. Now start v.3

 

looks good, fabrication

 

putting the injectors on the bottom isnt the best idea but i have heard that making the bosses a little further away from the flange is a good thing. not sure why though.

 

the idea is that the further you get back from the valve the more time the fuel has to spread out laterally and you get better atomization of the fuel. You should theoretically lower your injection angle as well, but before you were using gravity to pull the fuel down where as now you're using the pressure force to fight gravity. granted the weight of each droplet is miniscule and gravity only has a VERY short amount of time to affect it...its still worth thinking about. /over analyzing it.

good job.

 

what kind of injectors are those bosses for?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 743power &raquo;</TD></TR><TR><TD CLASS="quote">what kind of injectors are those bosses for?</TD></TR></TABLE>

precision 1000cc

 

Nice head flange. Looks good

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ~RTErnie~ &raquo;</TD></TR><TR><TD CLASS="quote">the idea is that the further you get back from the valve the more time the fuel has to spread out laterally and you get better atomization of the fuel. You should theoretically lower your injection angle as well, but before you were using gravity to pull the fuel down where as now you're using the pressure force to fight gravity. granted the weight of each droplet is miniscule and gravity only has a VERY short amount of time to affect it...its still worth thinking about. /over analyzing it.

good job. </TD></TR></TABLE>

Now you have to alter the injector pulse timing.... right? You are moving the injector so how do you account for the delay of fuel?
I guess I can see how it can atomize better, but at the same time wouldn't you have a greater chance of gumming up the end of the runners with crud?

I will give the fabricator credit.... he is doing a pretty good job on the fab work. It looks much better than rev 1.

Where did you get the runners and the velocity stacks?

 

Moving the injectors up the runner is great for high RPM performance. It just kills the motor every where else and that is why the factory puts them close to the head.

If you go for a V3, I'd suggest a wider plenum. Something that gets the sides of the plenum away from the edge of the velocity stacks. Also, aiming the throttle body AWAY from the runners can improve air distribution. The solid model below kind of shows what I mean. The plenum is relatively thin, yet wide. Basically, I've tried to obtain about 2" of clearance from every point of the inlet area. The throttle body is also aimed so the air "crashes" into the back of the plenum to prevent it from blowing directly over the top on any inlet.

 

with regards to the injectors being further up the runner than the factory position, will work ok. They are not that much further up than the factory ones, and my Power Fc has the abillity to adjust the fuel as I please.

And the timing of the fuel, will not be afected, since the intake valves still open at the same time.

 

timing of the fuel will be affected.... you are moving the injector farther away therfore you will need to advance the time of the injector pulse to pick up for the additional travel time.

It is not like you have fuel sitting on the back of the valve at all times and you just wait for the valve to open....

 

IMO - if you wanted a better stratified combustion you would have moved the injector boss's to the top of the mani where honda originally designed them to be but moved them closer to the flange. if you went a step further and took in account for the spray pattern of the injectors that you are using you would also have changed the pitch angle of how they spray into the cylinder.

What you are left with now is an upside down injector that is spraying the on top of the intake runner, now this causes worse stratified air fuel mixture because the fuel is pooling against the top and dripping down to the bottom. Atomized fuel burns, a puddle of fuel won't burn as well. you will find your engine running leaner as the rpm's increase and you will need to add more fuel acress the board.

but none the less that mani does look excelent !

 

 

over the week I had a chance to put the mani to the test.

dyno testing put out a amazing 575 whp and 403 wtq at 25 psi boost on 92 octane.

track testing was a bit more dificult, but it helped me get at the end of the track in 11.5 sec @ 130 mph. with my ek wheight at 2650 lbs.

 

get your suspension setup and the traction issues figured out and you can smash your ol 10.7

 

very nice, what numbers were you making before on the v.1