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For an upcoming spring project I want to make use of my extra rx8 engine and have some fun. Not all of my current concept is set in stone, and I have no intentions of trying to break any records. I might even make a build thread for it when the time comes.
What I need help with is a picture or even dimensional differences between the rx8 center Iron and any various rx7 center irons. In particular I am currently looking into the 87-88 Turbo2 center Iron.
Focus points:
Side by side picture of the intake manifold runners. (concept involves mating the rx8 LIM to an Rx7 center housing) From pictures I found in my search, the REW center Iron has higher intake runners and would not be close enough.
here’s the T2 iron though; in addition to higher ports, there’s also the other cavity port below them
I’ve pretty much explored about every thing possible, but maybe not every last crazy idea. If you want to pm me we can discuss whatever it is you’re considering.
Just to clarify for anyone else I am looking for pictures of both the center Irons side by side in the same picture. I know individual pictures exist, but various angles and distances of pictures are not as helpful as a side by side.
Just to clarify for anyone else I am looking for pictures of both the center Irons side by side in the same picture. I know individual pictures exist, but various angles and distances of pictures are not as helpful as a side by side.
Wish I could help with that but I'm not around too many disassembled engine blocks. Despite having 5 RX8's all have perfectly good engines still. Even the one RX7 my friend has still a long way away from needing a rebuild. Love your content and your style. Look forward to learning along with you.
Still searching, issue is that without physically putting the plates next to each other I have to try and go off of these different angles by comparing the tension bolts.
04-08 6 port Rx8(left) vs 86-88 NA S4 FC(right) Centerplate
In this picture I can't tell the height difference of the runners, but the S4 seem to be the closest out of any 13b plate. If anything the S4 plate appears to have enough material to work with and does not have the cavity just below the runners.
Differences to note is that the Rx8 coolant jacket above the injector port is smaller due to them angling the injector more towards the primary port. What is interesting is that it looks like the rx8 fuel rail may work on the S4 plate since it appears the assembly of the injector port and the mounts all changed by a relatively similar angle.
Have to admit I overlooked that housing likely assuming it was the same as the T2. I suppose you might be able to drill and tap the missing manifold bolt, but might be ok without. Not really sure under boost pressure. I’m assuming they went to the trouble of putting it there on the T2 for good reason though. An RX8 manifold in general being built for NA with long sweeping radius turns has a lot of overhang out past the mounting surface. Which additionally eats up a lot of space on that side of the engine. The APV motor being on there; more so.
Not really going to comment much otherwise having shared my thoughts privately and will let your thread do it’s thing. My analysis is elsewhere on the forum and still the same.
I have decided to put this project on the backburner and save money for the Rx8#3 or the REW funds, mainly due to Team's explanations. Although I would still like to find an actual side by side comparison just to see if I was correct that the Rx8 LIM could have fit. As far as I can tell it almost appears like Mazda copied the runners into the rx8 and then just reangled the injector assembly.
One of my friends is planning to buy an FC and rebuild it, so perhaps an Iron may be available in the future for free mockup purposes.
01-07-2021, 12:55 AM
LF Pics of rx8+rx7 Center Irons
I suppose you might be able to drill and tap the missing manifold bolt, but might be ok without. Not really sure under boost pressure. I’m assuming they went to the trouble of putting it there on the T2 for good reason though. An RX8 manifold in general being built for NA with long sweeping radius turns has a lot of overhang out past the mounting surface. Which additionally eats up a lot of space on that side of the engine. The APV motor being on there; more so.