Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: colin5524 on January 04, 2007, 06:14:00 PM

Title: Intake manifolds
Post by: colin5524 on January 04, 2007, 06:14:00 PM
Okay ,thinking to fab up an intake at some point but wondered what gains i would make here is a couple of pics from guys at ausrotary forum had on there 13b\'s
(http://i103.photobucket.com/albums/m134/colin5524/120ze.jpg)
(http://i103.photobucket.com/albums/m134/colin5524/P1000808.jpg)
now does anyone here run an aftermarket intake manifold, and what are some of you guys FC\'s bhp?
cheers
Title: Intake manifolds
Post by: McCARTHY on January 04, 2007, 06:59:57 PM
i will be running an after market inlet manifold with 80 or 90mm throttle body. Provided you get the sizes right you can in prove the throttle responce and horespower.

Each application will differ due to mods like turbo porting etc. What else will you be doing ot your car?
Title: Intake manifolds
Post by: kev-yorks on January 04, 2007, 07:16:14 PM
Quote from: McCARTHYi will be running an after market inlet manifold with 80 or 90mm throttle body. Provided you get the sizes right you can in prove the throttle responce and horespower.
 
Each application will differ due to mods like turbo porting etc. What else will you be doing ot your car?
A word of warning you can run into drivability issues with a single large throttle body! In many cases you will get just as much power but with good drivability with two mid sized ones with a slight lead on one of them to give progressive initial opening. Porting the stock throttle body and removing the secondary butterflies is also a good option with good gains in flow while retaining low speed throttle control.
Kevin
Title: Intake manifolds
Post by: 88GT-R on January 04, 2007, 07:17:35 PM
No matter what anyone tells you, it all depends on your end goal. The inlet manifolds shown are VERY good for a Drag setup. When contemplating designing or modifiying an inlet manifold, the are a few factors to conscider...pulsation being the overiding factor. This is most noticable at part throttle openings, and low speed manouvering.

My setup is currently making a conservative 430atw@0.91bar. This is from a special 13b-RE block. If you have any queries please email me at
arty26we@yahoo.com

Cheers,
John
Title: Intake manifolds
Post by: Brett on January 04, 2007, 07:21:30 PM
Moving this to the technical section. :wave
Title: Intake manifolds
Post by: 20B_boy on January 04, 2007, 07:32:09 PM
Quote from: McCARTHYProvided you get the sizes right you can in prove the throttle responce and horespower.
Easy to lose throttle response, hp and/or torque though too. Lots of experimentation required :D Try chopping about a stock plenum and/or trying a big throttle body on it and see what happens!
Title: Intake manifolds
Post by: McCARTHY on January 04, 2007, 07:54:26 PM
yes i totally agree. Its very easy to get it wrong much more easy to get it wrong than right..... As suggested removing the secondary butterfies it the first easy option to improve the situation.

What else are you going to be doing to the car?
Title: Intake manifolds
Post by: kev-yorks on January 04, 2007, 07:55:57 PM
Dont just remove the secondary\'s there\'s a lot of Ali you can remove as well to aid flow.
Kevin
Title: Intake manifolds
Post by: stuart wizy on January 04, 2007, 11:02:40 PM
Ive been looking into this for quite a while now , see my pics of my inlet on project page, It seems custom inlets are usefull if your looking for really big power from really big flow,  but only at high revs then this is the way to go, the bigger the dia your runners the more cfm will flow through them, as long as your turbo is big enough to pump the air through your runner size diamater.
The problem is the bigger you go runner dia, the slower the flow or airspeed you will get until the turbo spools up, im worried that mine wont run of boost because the air speed will be that slow and the fuel wont mix with the air because of this low airspeed, also the bigger the ports the less vacum you get sucking in which will slow airspeed down  even more at low revs.
almost all really high powered drag cars in the uk are running bigger custom inlets and plenums for serious flow, check norris designs evo inlet manifold or all the 1000bhp skylines.
Title: Intake manifolds
Post by: colin5524 on January 04, 2007, 11:19:15 PM
looking for around 400bhp going to be running a garret GT42,1600c secondaries, bigger fuel pump,homemade fuel rail,frount mount intercooler, ecu wise i was thinking apexi fc, what do most guys run ecu wise? Also going for porting but indecided on how far to go any suggestions. and cheers everybody :)
Title: Intake manifolds
Post by: stuart wizy on January 04, 2007, 11:33:02 PM
antnicuk has built an fc i think with a fd uim making around 400 horse, he will tell u more,
I dont think u need custom inlet for 400 bhp unless you want to build one anyway, always good to see people building and developing there own parts mate, go for it I say:Thumbsup!
Title: Intake manifolds
Post by: antnicuk on January 04, 2007, 11:39:02 PM
You will easily get 400 flwhp and could well see 400 rwhp with a good set up, i went for the FD UIM, removed the secondary butterflies.  I only really went for this because it meant i could use a greddy elbow and the FD TPS as i have an FD Apexi with a modified loom.    Cris at reworx got 600 fwhp from the stock TII inlet with a different elbow.
Title: Intake manifolds
Post by: McCARTHY on January 05, 2007, 12:19:02 AM
are you doing this on a TII lump or using a FD lump?
Title: Intake manifolds
Post by: 88GT-R on January 05, 2007, 12:24:28 AM
Don\'t believe everything you hear.....
Title: Intake manifolds
Post by: McCARTHY on January 05, 2007, 12:27:44 AM
Quote from: 88GT-RDon\'t believe everything you hear.....

this relates tooooo?
Title: Intake manifolds
Post by: 88GT-R on January 05, 2007, 12:50:38 AM
I won\'t name and shame, but i would suggest that MRC is not the only fountain of knowledge....
Title: Intake manifolds
Post by: rmagictastic on January 05, 2007, 08:49:23 AM
Quote from: 88GT-RI won\'t name and shame, but i would suggest that MRC is not the only fountain of knowledge....


hehehe..bang on John.

GENERAL STATMENT :

As John said earlier, first off what are you trying to achieve?? Better air flow is not the be all and end all of rotary power, you can shove as much air in to the chamber as you want but when you get to a certain stage other things come in to consideration, such as Pulsations from the rotor (as John said), exhaust ports, big timing issues.

And what most people dont consider is that its all well and good having 450,000 Bhp but where does it come in the revs?... and doing all of this stuff will affect the power band on a rotary probably more than everything else!!

By the way i like modding and trying new stuff, just saying that your best off having a goal to achieve or you can end up with a machine that is excellent when your doing 6000rpm, but below that can be a dog.

Rmaj:driving
Title: Intake manifolds
Post by: colin5524 on January 05, 2007, 10:51:07 AM
i would like to use the original FC engine as it was rebuilt at 50000 odd miles and only has around 65000 on the clock?and yes i have looked at other sites such as FC3s.org etc but there were alot of bad attitudes there, ausrotary was good but site was down and everybody seemed quite friendly here :)
Title: Intake manifolds
Post by: 88GT-R on January 05, 2007, 11:46:46 AM
Still havn\'t stated what you wish to achieve....
Title: Intake manifolds
Post by: rmagictastic on January 05, 2007, 12:20:28 PM
Quote from: 88GT-RStill havn\'t stated what you wish to achieve....


I CONCOR DOCTOR:bandit
Title: Intake manifolds
Post by: colin5524 on January 05, 2007, 02:14:44 PM
Sorry looking for around 400bhp
Title: Intake manifolds
Post by: rmagictastic on January 05, 2007, 02:16:13 PM
drag?
circuit?
street?
...........?????????
Title: Intake manifolds
Post by: stuart wizy on January 05, 2007, 05:05:00 PM
has anyone tried a custom inlet runner and plenum in this country???
I know ross uses the cosmo uim with the bigger runners but has anyone tried to go bigger?? apart from pp port that is
Title: Intake manifolds
Post by: 88GT-R on January 05, 2007, 05:07:10 PM
Yes, i have had the pleasure...thats why i have said what i have said...:)

John
Title: Intake manifolds
Post by: stuart wizy on January 05, 2007, 05:11:00 PM
what size and what happened then, any pics
Title: Intake manifolds
Post by: colin5524 on January 05, 2007, 05:21:22 PM
mostly drag with the hope of a few trips to the mainland for a little track action
Title: Intake manifolds
Post by: stuart wizy on January 05, 2007, 06:58:20 PM
found a few pics for u collin
they seem to be made and used all over the world apart from here in the uk,
The big question is WHY not??
ive got a link somewhere on dimensions and how to make a inlet man and plenum explaining about velocity stacks inside the runners to speed up airflow
Title: Intake manifolds
Post by: colin5524 on January 05, 2007, 09:47:10 PM
Thanks for the pics!
Title: Intake manifolds
Post by: allstaruk on January 05, 2007, 11:45:29 PM
They look nice, was thinking about doing somthink with mine too.

A