ClubRoadster.net banner

Why has the 4G63 swap not been done?

31K views 59 replies 39 participants last post by  Derail20T 
#1 ·
Considering all the information that is out there on RWD swaps using the 4G63 with a TII tranny and B2600 bellhousing. There is a forum dedicated to the swaps. Even some RX7s have the swap....I guess this would be a good read. Just from the pictures I have seen, the first problem would be the exhaust being on the passenger side in the engine bay as opposed to the drivers side. That would be a problem with the PPF...Discuss

http://www.projectzerog.com/

http://www.projectzerog.com/rx7transmissions.shtml
 
#4 ·
Mongrel swaps are not common in general. I'm sure there is a Miata somewhere (Trinidad, Thailand or Russia?) that has this swap that we just haven't seen yet on CR.net. But it just doesn't make much sense where there are easier and more cost-effective swaps out there (FE3, LSx) that make more than enough power for the little, short wheelbase Roadster.
 
#14 ·
Considering all the information that is out there on RWD swaps using the 4G63 with a TII tranny and B2600 bellhousing. There is a forum dedicated to the swaps. Even some RX7s have the swap....I guess this would be a good read. Just from the pictures I have seen, the first problem would be the exhaust being on the passenger side in the engine bay as opposed to the drivers side. That would be a problem with the PPF...Discuss
No one says the exhaust needs to run under the car and out the back. There's ways around that.

The big problem is the oil pan sump will want to occupy the same space as the steering rack. So you'll need to fabricate a rear sump oil pan like I had to do on my SR20 Miata. What people don't realize on these high HP engines is that the oil pan becomes a structural member of the engine and helps to hold it together. I solved this by having mine machined from a 74# brick of aluminum. The end product cost about twice what I pad for the Miata in the first place; about $2K.

Also, not sure how tall that engine is, but between oil pan depth and hood height, the engine might be too tall for the bay. That was also the problem with the SR20. From 10ft it looked like it was exactly the same size as the 1.6 engine, but in reality it was about 15% bigger everywhere.

The other big problem is that all of the suspension is designed for a ~130hp car; not a 300hp car. Replace brakes, build new axles, new hubs, reinforce chassis, etc. This is why crazy off the wall swaps like this continue to hover at close to $15K by the time the car gets on the ground (assuming the engine is inexpensive or free),
 
#18 ·
Well if it uses a tII tranny you might as well use the tII rear end. That swap is already documented. A pain in the ass but doable. I believe there was a vender that offered bored hubs but can still do it on a per order deal. If you were to get the measurements of this engine, and it could fit, I could see this not being super difficult. The oil pan will be your main hurdle.
 
#20 ·
I can tell you on, that the two biggest issues aren't going to the PPF or the exhaust. It will be finding the correct block, and custom oil pan. To use the T2 transmission you can't just use the motor out of a DSM. You have to find one of the semi rare RWD blocks.

Someday i would love to either build a 4g miata or 4g FC, but it isn't a cheap swap at all.

Parts need just for the motor:
Wideblock 4g63/4g64/g63B--(only comes in SOHC)
DOHC head off DSM or EVO(depending on which side you want your exhaust)
Custom intake manifold
custom turbo manifold(could maybe use stock)
custom oil pan.
 
#25 ·
I have seen one 4G swaped Miata. It was a drag car..and Bryan knows what I'm talking about. It's been done.

As for the exhaust...remember that the 13B has the exhaust on the opposite side to the B6/BP. FE also requires a customized oil pan...but at least the transmission bolts up.
 
#30 ·
the 4G63 motor for a lack of words DECENT stock. one you start to mod them, iv never seen a engine get so unrelyable so quickly. i havent know anyone with a DSM that hasent rebuilt the motor a dozen times because it always fucks up.

if someone is interested in doing a 4G63 swap into a miata i would suggest getting one out of a EVO instead of a old Talon or Eclipse. the evo 4G motors can actually take some abuse and be relyable.
 
#34 ·
So much bad, and misinformed information is being thrown out in this thread.

The 4G63t's tend to be unreliable due to the people working on them. They can make huge power for very little money, so maintenence is often overlooked. Typically the people owning these cars are really cheap.
I know a lot of people dd'ing 4-500hp motors, some big power cars with stock internals. Big power always comes with problems. Especially when your making 100+ hp per cyl.

Only the later 7bolts really suffered from crank walk.

The original reason why I got into miatas was to do this swap. I have too many things on my plate now.
I have an early galant vr4.
 
#35 ·
+11000

4g63 are really unreliable like you said due to the owners. Now days most owners are young teenagers that get the cars for $1000 and then don't do any maintenance and just put a few hundred into in mods and wonder why it breaks.

Also any motor in the whole world(minus Rotaries) can crankwalk, but your right late model DSM 7 bolts are more likely, but you can thank American builders as the 7-bolt for the eclipses were built state side and they f**ked the motors.

One day I will either build a 4g63/4 miata or rx7 as I really like the powerband and feel of the motors.
 
#36 ·
I don't really see a point in going through the trouble to swap a 4G63 into a Miata. I have an Evo and I like how easy it is to make power and how reliable mine has been even with increased boost level and daily beating to redline. I still think you'd be wasting your time trying to swap the engine into a Miata. You might as well just boost the engine your Miata came with since they can already take boost fine. Or do you want to swap a 4G63 to make 400+ whp? Still a waste. Go do some sort of V8 swap where someone has already done the homework for you.
 
#40 ·
I can name a few reasons(why someone would swap motors). 1) making over 300 on a B6/BP is really starting to tax the motor(stock) yes it has been done, but at that point your have triple the power and things break easier. 2) some people just prefer the feel of one motor over the other, it why some people prefer the B6 over the BP 3) last something different. yes going V8 could be cheaper, easier and such, but if you wanted something a little different then doing a random motor swap would be the key.

Just so you people know the 4g inthe 03-06 evolution is a 7 bolt. I ran my evolution for 5 years modded and it nrlever broke down on me once. **** at 110,000 miles I was DD on low boost making 340/360 wheel and never had a problem. Look into stock frame evos making 500/500 and daily driving it.
any 4g made after 92 is a 7-bolt. Doesn't matter what it came in, if it is a post 92 it is a 7-bolt. Just that the lovely factory in Indiana f**ked up the specs and well the rest is history for USA made 7-bolts. Same story with the Mk3 supra's with the 7m, a f**K on specs and they blow headgasket every other day.
 
#39 ·
Just so you people know the 4g inthe 03-06 evolution is a 7 bolt. I ran my evolution for 5 years modded and it nrlever broke down on me once. **** at 110,000 miles I was DD on low boost making 340/360 wheel and never had a problem. Look into stock frame evos making 500/500 and daily driving it.
 
#47 ·
I see alot here interesting! The 4g63 is was offered in FWD or AWD, like said above the 7 bolt blocks were known for crank walk & I have seen Honda motors that have crank walked. As far as not being relaible I have alot of DSM friends making over 600 awhp, one makes 601 awhp on a stock bottom end on his old GT35r set up & has done this for the last two yrs. There is a guy with a 4g63 swap in a FC3S, he lives in Ohio & there is a white drag FD3S with a 4g63 swap. Starions & Conquest are essentially the same car running the 2.6 four cyclinder a 4g54 I believe RWD. To the OP you may want to check some of the DSM forums to get a better idea on the 4g63.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top