Custom Intake Manifold with Honda Throttle Body
 

I just wanted to post some pics of the custom intake manifold I built for my 89 Turbo II. I used a Honda 70mm throttle body and TPS for a cleaner look. I just wanted to get some feedback and opinions on whether you guys liked it or not.

I enjoy how its unique...definitely never seen that... Too boxy for me though. I like the original intake manifold better. Have you used it yet?

Coil pack bracket
 

I am running a EMS Stinger on my 7 and made a custom bracket to mount 4 coil paack facing straight up, then bracket places the four coils in the stock location of the trailing coil pack.

not yet, just finishing the little things here and there before I do an initial base map and then take it for dyno-tuning.

I think the Coil pack definitely will look better like that

Very sweet. It reminds me of Aaron Cake's manifold.

It doesn't look bad.... I'm just still digesting putting Honda parts on an RX-7 :puke: Why not a Q45 throttle body?

how is the throttle sensitivity with the single throttle body? is it really twitchy?

Got any shots of the inside of the intake manifold? Looks good. Post the dyno sheets when you have them...

After alot of searching around for a throttle body, I chose the Honda one mainly for the cosmetics and the clean mount of the TPS versus the stock dual plunger setup on a bracket running off of thirty rings on the throttle body, maybe that was a little exaggerated but even though it is a honda throttle body, and I do despise most of them mostly because of their inability of understanding the fact that intake +fart can+ altezza's does not equal race car, it is a very nice looking and clean throttle body.

I havent quite got to the point of running it yet so I am not sure how it is going to act, I would imagine with the proper tuning it will work good.

Aaron Cakes manifold was the main reason I decided to build my own, I originally wanted to do a fd upper intake, but then I decided I wanted to make it look as clean as possible so I made my own.

Dude that looks great, mad props. Love to see how this works out.

Very nice fab work man, that set up does look clean. As far as the the Honda throttle body who cares if it works then it works.

I'm just curious if this is going to result in a noticeable loss of low end response because it doesn't open in two stages like the stock TB.

So... it says in the 87 FSM that the factory throttle body diameter is a total of 135mm (45 mm primary and 2 45mm secondaries). Im not sure if the S5 is different, but if the honda throttle body is just 70mm, isn't that a giant difference? Does throttle body size matter that much on a turbo motor? Or would the giant... plenum (i think thats what its called) make a difference? But it looks like you did a great job with the fab. And that TB is surely way sexier than the factory one.

Very clean and good looking. I went a little different route but the same concept.


http://img.photobucket.com/albums/v2...hrotlebody.jpg

http://img.photobucket.com/albums/v2...p/P8090001.jpg

Mathematically, you are right. I haven't use "pi R squared" in a while, but

45/2 = 22.5, 22.5*22.5 = 506.25, 506.25*3.1416 = 1590.435, 1590.435*3 = 4771.305

70/2 = 35, 35*35 = 1225, 1225*3.1416 = 3848.46

So it's obviously smaller. Don't go around thinking the stock TB is the same as a single round 135mm throttle body though. A larger circle gains exponentially more area than having several smaller circles. A 135mm throttle body would have an area of 14313.915!! It appears the Honda TB has 80.66% the area of the oem unit. I agree, it does look very nice. I'm just waiting on real dyno (not butt-dyno) numbers to see if this was negative progress.

That makes sense. I imagine having 4 less butterfly valves in the way would help as well. This should be interesting. Good luck Tproductionz.

stacher I would like more info on what your did there.

pretty cool. i did a lot of searching also. and i went with an 80mm mustang TB. its TPS compatible with Mazda and also has no "junk" on it.

very nice!

Sen2^2 you have more info on the TPS compatible part? Cause that would be of great use for something I have been thinking about doing.

just because the total cross sectional area is smaller doesnt mean that it will flow any less, with one large opening the flow characteristics are drastically changed as there is less side wall surface to slow down the flow as velocity of the air at the wall is theoretically zero.

I would have made the plenum out of a cylinder for a smoother transition of air in and out of the plenum.

I like it. :D

It should be pretty good in the low and/or mid-rpm range with those long runners. The plenum looks a bit large, and I assume you didn't put bellmouths on the runners, but I think it will work pretty well. Even if it isn't so great, it still looks way more cool than a junkyard FD intake rigged to a FC engine.

My guess is that it will have too much response down low, making the car twitchy. However, I am not familiar with that throttle body, and it may have a built-in mechanism that tapers the opening rate.

In general, a smaller plate gives better throttle response and better low-rpm performance, while a larger plate gives better high-rpm performance. Multiple-plates, which are standard on most production street cars, allow for better engine control at the cost of peak performance.

Throttle plate rule of thumb for turbocharged engines, reference "Forced Induction Performance Tuning" by A. Graham Bell.
50mm - 250hp
56mm - 310hp
62mm - 390hp
70mm - 500hp
75mm - 600hp
85mm - 750hp
90mm - 830hp
100mm - 1000hp

He does have a giant plenum. The plenum is the big fabricated metal box between the throttle body and the runners.

cant remember exactly wich wire is wich. but it has the same range, wires, ect. you can find the info googling it...

and mine is aftermarket brand new for 80 bucks! pretty sweet deal.