Starting 4g swap into my 94 fd rx7. Thoughs and advice?

Sketch_hs · Post by **Sketch_hs** » Wed Apr 11, 2012 11:14 pm

The car is a 94 FD rx7 I just bought recently. Had a mkiv supra before with tons of power.... but was involved in an accident and it was totaled. Money to play now thanks to good insurance so project FD is next!

So far I've sourced the bell housing from a b2600 to use a wideblock 4g64. I'm not totally set on that bell houing but it seemed like a nice solution. I like the stock FD transmission, it has good gear ratios and is cheap to rebuild and replace. Also I really don't want to loose the stock brace from the diff to the tranny.

I can get evo engines pretty cheap from my last employer (EVO tuner, WORKS at Infineon raceway) but I'd need an adapter plate and custom clutch, flywheel stuff probably etc. Also the exhaust is on the wrong side vs the 13b (less room for turbos and a downpipe)

I'm still researching and trying to decide on which head and intake manifold to use. I want to use the best factory equipment for the setup. This will be a street car with AC, PS etc.... Likely going to use AEM EMS.

Anyone know if there is a factory oil pan/sump setup? It needs to be rear sump for this car. And the intake manifold, will anything bolt up facing the right way on a 2g head? I'm guessing that would have to be custom also?

Functionality and fitment is my greatest concern, cost is secondary.

I'm excited for this project to get moving. About myself, I've done a few conversions (1jz FC rx7s and 2jz datsuns, v6 mr2s, v8 510s etc etc)

I work on Audis at a specialty shop called "2Bennett Audimotive" in Davis, CA.

-Tyler Orr

jeffball610 · Post by **jeffball610** » Sat Apr 14, 2012 5:54 pm

Keep reading the forums. Most of your questions can be answered in detail. But here's some quick answers:
Pick a block and go with it. If you really want the FD trans, make sure the motor will clear with the trans in the stock location. The biggest firewall fitment issues are the cam angle sensor and the thermostat housing. If you go with an EVO block or narrow block options, you will need another transmission or see if the Mazda housing can be modified to work.
If you stay away from an EVO head, you can use the DSM stuff and the exhaust is on the passenger side like the FD had. You also won't have to worry about the injectors needing to be a part of the intake manifold.
JMF and other race companies can simply flip the manifold over for ease of use and actually sell a RWD setup. As long as it clears all of the other components, this may be the option to go for. There should also be plenty of room for the AC compressor in the stock location.
There is no current solution for a rear sump pan. You can go with a dry sump solution which may limit the use of other components like AC, or you can have a custom fabbed pan with the oil pickup at the rear of the block.
Hope that helps. Start posting progress of your build in the build section if you decide to go this direction. If you're set on keeping it a high revving motor like the Rotary, then a 2.1L build might be what you're looking for.

SOB Racing · Post by **SOB Racing** » Fri Jun 08, 2012 1:07 pm

I'm doing a 4g63 swap on a 87 RX7 and determined that I'm going to have to make an oil pan from scratch as well. There's a guy on RX7.com doing a 4g63/FD swap and he modified the K-member so he didn't have to make an oil pan

quicktalon11s · Post by **quicktalon11s** » Sat Jun 09, 2012 1:31 am

kens custom chassis sells a rear sump pan for rwd 4g63 motors. i wanna say modern automotive performance sells one too but you have to call them.

Richard · Post by **Richard** » Tue Jun 12, 2012 9:11 am

You can use modified evo 8 intake manifold if you use a 2G head

a stock evo 8-9 exhaust manifold & turbo can be used with an additional exhaust flange as a spacer.
But the alternator would probably be in the way and moving it could cause a problem if you want to keep A/C

JDOliver · Post by **JDOliver** » Sun Jun 17, 2012 9:55 am

There is a lot of discussion on the Evo vs. 1G head and flow. Personally I think most of the discussion becomes mute once you start adding boost, but that's just my theory.

The bigger issues with deciding on the head relates to the intake side and where you want your fuel injectors. The 1G are part of the head and Evo are part of the intake. Like others mention, the intake and exhaust sides are swapped also and picking the wrong way to go will give you significantly more fitment problems.