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this is my KLZE in my car with a straight neck intake manifold http://imgur.com/6hCzt.jpg" onclick="window.open(this.href);return false; ...just wondering if i can get some advice on what you guys think i should do here...ive increased air volume in the manifold and im assuming that its having an effect on something...i was driving it for like 2 weeks and i was getting 15 mpg =/ and idling at like 2,000 rpm... the distributor (i think) just died the other day...so im replacing that...

do you guys have any ideas on a route i should take? i dont even know where to begin? and i know "get a curved neck" is going to be an answer, but i was just looking to make an alternative to buying one...do you think its bad for my engine? ok i know im gonna get some negative feedback, but i just want advice on how to keep this and make it run smoothly impossible?

heres a couple other pictures:

http://imgur.com/na0i6.jpg" onclick="window.open(this.href);return false;
http://imgur.com/zQJZ6.jpg" onclick="window.open(this.href);return false;

and i know the engine bay is a mess and the wires are crossed (which i got complaints about already) but that was all done really quick just to get it running these pictures are like a year old now...

let me know what you guys think...

What the F did you do to your throttle body? That needs to stay ON the intake manifold, no wonder your car's running weird. If you're gonna fit the straight neck then do it properly.

You said you know "get a curved neck" would be an answer.
Well, guess what: "get a curved neck" is THE answer. That or get a hydro electric brake system, so you can get rid of he booster.

Not only you increased your plenum volume with that "mod" ( ), but you completely screwed up your VRIS.
Now, believe it or not, things like the plenum volume are calculated by ENGINEERS (that is, by people who know what they're doing), to give you the best RPM range for your engine, and the best torque figure for a street application. The VRIS takes that a step further, by changing the plenum volume in a CONTROLLED WAY, to give you the best torque figure across the whole RPM range. Both the plenum and the VRIS system work by RESONANCE. That elbow you put on your engine just lowered the resonant frequency of your plenum to a point where it's completely useless.

GET RID OF THAT STUPID ELBOW, AND EITHER GET A CURVED NECK, OR MODIFY YOUR BRAKE SYSTEM, IF HAVING A STRAIGHT NECK IS SO IMPORTANT TO YOU.

get a curve neck is not the answer at all.. it has nothing to do with your intake manifold, its that hack job sideways throttle placement

Do you have a K8 throttle body lying around ? you need a K8 throttle linkage

first remove the dual mechanism off your i assume is a KL31 tb.. use the smaller round K8 linkage on the kl31

It clears the brake booster just enough to be safe. its simple and took myself and projectzemx3 all of 15 minutes to figure out once we got both throttle bodys off to look at them side by side.

Using a K8 manifold might work, but you'd have to make a side by side dyno comparison to see how it affects performance. Intake plenums are calculated in relation with the total engine displacement, so you can be sure using a 1.8 l intake manifold on a 2.5 l engine WILL make a difference.
My guess is you'll lose some low end torque. If you're ok with that, it can work.
But, at least in my opinion, settling for lower performance when you can get the right IM at a junkyard for just a few bucks, doesn't make sense.

Inodoro Pereyra wrote:Using a K8 manifold might work, but you'd have to make a side by side dyno comparison to see how it affects performance. Intake plenums are calculated in relation with the total engine displacement, so you can be sure using a 1.8 l intake manifold on a 2.5 l engine WILL make a difference.
My guess is you'll lose some low end torque. If you're ok with that, it can work.
But, at least in my opinion, settling for lower performance when you can get the right IM at a junkyard for just a few bucks, doesn't make sense.

He wasn't talking about the whole IM, just the throttle linkage.

Inodoro Pereyra wrote:Using a K8 manifold might work, but you'd have to make a side by side dyno comparison to see how it affects performance. Intake plenums are calculated in relation with the total engine displacement, so you can be sure using a 1.8 l intake manifold on a 2.5 l engine WILL make a difference.
My guess is you'll lose some low end torque. If you're ok with that, it can work.
But, at least in my opinion, settling for lower performance when you can get the right IM at a junkyard for just a few bucks, doesn't make sense.

I think you missed the point.... the picture i posted is a Straight neck ZE manifold with a KL31 throttlebody, the only thing K8 there is the linkage where the throttle cable attaches (see projectzemx3's worklog)

the right IM is already on his car

JWMX3 wrote:
I think you missed the point....

Yep, I think I did...

Sorry...

This is exactly what I did. I put the K8 bell crank on my KL31 throttle body. I also installed a modified MX-6 brake booster.

The only thing I don't like about it is that I have to unbolt the bell crank from the TB to remove the TB because it won't go past the brake reservoir with the linkage installed. But it's not so bad.

I would like to know how the throttle feels with the stock 2-stage bell crank. I'm thinking there is probably a good reason they did that.

So this is the all famous secret on fitting the straight neck into an mx3?? I remember a few years ago there were some members here that would refuse to help a brother out on fitting the straight neck. Great post!

wytbishop wrote:This is exactly what I did. I put the K8 bell crank on my KL31 throttle body. I also installed a modified MX-6 brake booster.

The only thing I don't like about it is that I have to unbolt the bell crank from the TB to remove the TB because it won't go past the brake reservoir with the linkage installed. But it's not so bad.

I would like to know how the throttle feels with the stock 2-stage bell crank. I'm thinking there is probably a good reason they did that.

the 2-stage was apparently for throttle response... but ive driven both and feel no difference.. projectze's car hauls @ss too so I would throw that theory out the window, just because mazda changed it for the better, dosent mean it worked.

we originally did the mx6 booster as well, its unnecessary but definetly not as crammed in there. worth the extra work for a REALLY clean install i think.

hec - it was those boys from atlanta that fit the straight neck first, but they wanted to keep it all hush hush because they wanted to be special

i though this myth was busted a long time ago, i guess lots of members missed that thread !

JWMX3 wrote:

wytbishop wrote:I would like to know how the throttle feels with the stock 2-stage bell crank. I'm thinking there is probably a good reason they did that.

the 2-stage was apparently for throttle response... but ive driven both and feel no difference.. projectze's car hauls @ss too so I would throw that theory out the window, just because mazda changed it for the better, dosent mean it worked.

I agree with JW - I prefer the K8 one stage TB.

There's another answer that should be mainstream by now; KLG4 IM. If you port match it to the square port heads, and knife edge the divider, you'll have airflow as good as the curve-neck, with closer VRIS points. They come from 98-2002 626 V6s. You still have to use the K8 linkage, but it's nowhere near the brake booster.

The only (good) reason I wanted to put a straightneck in my car was to get the KL31 cams and not have to source a different manifold.

The other (childish) reason was to be special...though I didn't need to...my mom already says that I am.

When I want people to know I'm special, I just wear a white helmet, and lean forward when I walk.

But, seriously, the straight neck is viable, and many people have pulled it off, but, also, many people have broken their booster. The short booster idea is awesome.