DIY Honda B18 intake manifold-on-miata kit
Hey all. You may or may not have seen the thread in engine performance about adapting a honda b18 intake manifold to the miata. The long of the short is that the intake port spacing on the Honda B16 and B18 is very similar to the miata bp. The honda manifold allows you to run a intake manifold with nice straight and balanced runners as well as a nice large plenum. Also the manifold allows you to run honda throttle bodies. You can find a used 70mm honda throttle body with iac and tps for well under $100! The manifold used is an ebay skunk2 knockoff manifold which can be purchased for ~$130. I have bought 3 different manifolds from three different vendors and each has been identical. This is what Im talking about:
EG EK Da DC2 B16A B16B B17A1 B18C5 Aluminum Cast Intake Manifold Upgrade Bolt On | eBay As of now, If you wanted to do such a thing you either had to design a custom flange or do some sort of drill and slot job on the honda flange. Ive designed and machined a weld on flange for myself and a few of my buddies and would like to throw it out there if anyone wants to buy one. The thread about the manifolds is: https://www.miataturbo.net/engine-pe...d-43103/page1/ So what Im offering is a flange that is port matched between an ebay b18 manifold and a miata 1.8 head. As of right now I have the nb 1.8 flanged ready to cnc but I can easily do a na 1.8 head with a little cad work. The flange looks like this: https://www.miataturbo.net/attachmen...old-ccnc01.jpg https://www.miataturbo.net/attachmen...old-ccnc02.jpg https://www.miataturbo.net/attachmen...old-ccnc03.jpg https://www.miataturbo.net/attachmen...old-ccnc04.jpg https://www.miataturbo.net/attachmen...old-ccnc05.jpg To do the job you would cut off the honda flange off the manifold like so: https://www.miataturbo.net/attachmen...old-ccnc09.jpg and weld on like so: https://www.miataturbo.net/attachmen...old-ccnc06.jpg https://www.miataturbo.net/attachmen...old-ccnc07.jpg https://www.miataturbo.net/attachmen...old-ccnc08.jpg Then weld. If you read through the original thread youll see that the biggest issue with this mod is the welds cracking. The fool proof way to prevent this is to use the stock miata manifold support. The honda manifold has the mass much further from the head then the miata manifold and puts a lot of stress on the welds. With the manifold I will include a weld on support bracket which will allow you to use the stock miata support. I have ran this setup for over a year (with poly engine mounts mind you) with out any issues. The support looks like this: https://cimg0.ibsrv.net/gimg/www.mia...970ed9085e.jpg https://cimg2.ibsrv.net/gimg/www.mia...8bb5ccd92d.jpg Im offering to make both parts to order for $100 plus shipping. Also, If you want to run a miata throttle body, I have made an adapter flange and throttle cable mount which allows you to do just that. I can make these 2 parts for an additional $50. They look like this: https://cimg6.ibsrv.net/gimg/www.mia...4db5fe9a6c.jpg https://cimg8.ibsrv.net/gimg/www.mia...b8917383a4.jpg https://cimg9.ibsrv.net/gimg/www.mia...dc61e72132.jpg https://cimg0.ibsrv.net/gimg/www.mia...e401f4d7a7.jpg https://cimg3.ibsrv.net/gimg/www.mia...f03a253bd7.jpg So if this is something you are interested in, let me know |
Wow. That's incredibly slick how you machined the new flange so the Honda manifold slips in before welding. Pricing seems super reasonable too.
i likes this idea. |
In!
|
Very cool indeed. Group buys will probably need vendor status tho.
|
Right now I'm just a guy who has a cnc machine. I haven't thought far enough ahead for group buys or what not. I tried to price the parts as fair as possibly could though, there is no point to this if it winds up costing more then a fancy fabed manifold. Let me know what I need to do to stay mt.net legal.
|
Oh I have no issues with this thread, carry on. Just pointing out something to keep in mind if this takes off.
Want to keep the vendors happy. |
Thats excellent! If I dont follow threw with installing carbs....
|
Should we PM to buy, or are you just gauging interest?
I would be in for a flange kit! |
Originally Posted by OneTwo
(Post 1361644)
Should we PM to buy, or are you just gauging interest?
I would be in for a flange kit! |
Shipping to australia?
Dann |
4 Attachment(s)
Here is mine by mike. He does a great job.
Attachment 231045 Attachment 231046 Attachment 231047 Attachment 231048 |
Can I ask one of yall for a approximate center to center measurement of the intake ports?
|
Originally Posted by nitrodann
(Post 1361667)
Shipping to australia?
Dann |
Subbed for future forfeiture of my paycheck.
|
Any possibility of selling a completed manifold?
|
Originally Posted by GreenNB
(Post 1361678)
Can I ask one of yall for a approximate center to center measurement of the intake ports?
honda side: 88.7mm - 86.2mm - 88.7mm |
Originally Posted by glade
(Post 1361698)
Any possibility of selling a completed manifold?
|
This is the one i bought.
Mike does a great job and is well worth the money. Honda Acura B Series DOHC vtec B16A B17A1 B18C5 Cast Aluminum Intake Manifold | eBay |
any before and after DYNOs with just the intake change?
|
Originally Posted by cyotani
(Post 1361800)
any before and after DYNOs with just the intake change?
|
All times are GMT -4. The time now is 10:02 AM. |
© 2024 MH Sub I, LLC dba Internet Brands