So I want to know if anyone has swapped a JDM FSDE into their MSP's. My block spun a bearing but my head is still good if I need to swap that over. But I want to know if the JDM blocks are identical and if it's possible to use the JDM head or if I should stick to the original USDM head.
Need a new engine, should I go JDM or USDM FSDE?
- Thread starter im2bad4ya
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okay, so I can definitely use the block? Are they the same internally? I know some older FSDE blocks had cast iron crank and the 98 (i think or maybe 99?) and up had the forged crank shaft. Also is the complete engine plug and play or do I need to use the MSP head? Are the cam shafts the same on both heads or is one set of cams better than the other (performance wise)?
uhm, what???
cool, I already knew that, this is like my 4th engine, i've just never done a JDM swapped one. Also the pics of the JDM engine looks like it has a different head and intake manifold, so wanted to see what the deal was with that, and if the cams are the same on the JDM VS USDM
Aren't the USDM and JDM FSDE blocks the same though? When you say "better" cams do you mean better performance wise or the build quality or both? So what's the best combination head for my MSP, are you saying use the USDM head with the JDM intake manifold and JDM intake cam?
hornsfan10609
Certified Mazda Tech
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- 2003.5 Mazdaspeed Protege x2
Blocks are the same, cams are different and the ZE has high compression pistons. Use either head with the JDM cams and IM.
I'm not using an FSZE, using the FSDE, just the JDM version. So from what I can gather, the USDM and JDM blocks are the same (assuming the JDM block is '99 and up). The only difference in the heads are the intake manifold, the intake cams and the way the ignition is set up. The JDM engine has the FP39 intake cam and the USDM has the FS1G intake cam. Both engines have the FSD7 exhaust cam. The JDM engine has coil packs and the USDM has the coil on top setup. I'll be swapping over the coil on top to avoid modifying anything but should I keep the JDM intake manifold or the USDM manifold? and which is the better intake cam?
hornsfan10609
Certified Mazda Tech
- :
- 2003.5 Mazdaspeed Protege x2
JDM cam is better, JDM IM doesn't have VTCS IIRC so it would be the better IM.
I'm pretty sure you're right about the JDM IM, but let's say all things equal, I removed the VTCS off the UDSM manifold, which would be the better manifold?
Also how and why is the JDM cam better? Remember it's not the FSZE cam. I couldn't find any specs on it other than it's stamped FP39.
hornsfan10609
Certified Mazda Tech
- :
- 2003.5 Mazdaspeed Protege x2
If you remove the VTCS you basically have the same thing as the JDM. JDM cam is slightly more advanced timing than the USDM IIRC. The 'JDM' cam was used in every FSDE motor outside the US and Canada.
The blocks are the same. The internals arent the same.
I.e. higher compression. USDM is 9.1:1 and JDM is 9.7:1.
Best combination would be, FS-ZE intake, JDM FS and USDM Block/Bottom end.
Ignition is the same for 99+ AFAIK. All 99+ JDM engines got coils on top, same with ZEs.
JDM FS dont have teh FP39 cam. The key is FP (1.8). JDM engines utilise FSH9 intake with FSD7 exhaust cam.
JDM cam is much better over the US cam. Will improve your upper rpm massively
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The blocks are the same. The internals arent the same.
I.e. higher compression. USDM is 9.1:1 and JDM is 9.7:1.
Best combination would be, FS-ZE intake, JDM FS and USDM Block/Bottom end.
Ignition is the same for 99+ AFAIK. All 99+ JDM engines got coils on top, same with ZEs.
JDM FS dont have teh FP39 cam. The key is FP (1.8). JDM engines utilise FSH9 intake with FSD7 exhaust cam.
JDM cam is much better over the US cam. Will improve your upper rpm massively
I'm not sure if this is information you have based on a search (on this thread, google or otherwise) or if it's first hand knowledge. What I DO KNOW is that the JDM FSDE that I'm getting has the FP39 intake cam because that's what's stamped on it. I know this is an FS engine because it has the FS stamp on the block. And also, not all JDM engines have coil on top, only the ZE, the FSDE and FPDE I believe have the coil pack on the front of the the engine, like the one I'm picking up tomorrow.
This may be the info you got from the FS Engine Specs thread, but just because it's presently in a nice and clear way doesn't mean it's true, even a few posts down there are corrections, ones which were never amended into the original post.
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hornsfan10609
Certified Mazda Tech
- :
- 2003.5 Mazdaspeed Protege x2
Does it really matter that much? The cams will make about a 5hp difference either way.
Will make more then that. Really undervaluing cams.
Its first hand. Australian cars have all JDM gear, I have an FS my entire build started off using JDM FS.
If it has an FP cam its not an FS man. *ALL* FS-DE/ZE cams start with FS. Whether its FS1G, FSH9, FSD7, FS9 or FS1E. The FPs came with FP39 and FP47.
Only time that it could be an FS, is if it has an FP cam. But that would be stupid so not sure why that'd be the case.
I have had JDM FP, FS-DE and an FS-ZE in my time on these forums.
Well the exhaust cam on my JDM engine is FSD7 and the block itself is stamped FS NOT FP. That convinces me that it's an FS despite the fact that it has the FP39 intake cam.
Just because you think it would be "stupid" doesn't make it not true. So I'll take your word that you've worked with all the JDM F engines and know what you're talking about from experience. So in that case, do I have something unique? There's no way I really have an FP if the block is stamped FS
If you get the time check out the stamp on the Crank. If its a FS itll be FS01.
Ill have to check what the FPs were stamped. Think I still have a 1.8 crank downstairs.
Your misunderstanding why Im saying its stupid. The FS cam is 241 degrees duration intake on the JDM, it opens at 5 Degrees BTDC and closes 56 ABDC.
When you pair that up with the FSD7 Cam which is 230 degrees which opens at 48 BBDC and closes 2 ATDC. You get 7 degrees of overlap.
With the FP Intake Cam its 225 Degrees duration and opens 0 BTDC and closes 45 ABDC. This gives you 2 Degrees overlap.
Now despite what anyone says some overlap in a turbo car is a good thing, it decreases spool up. Your original motor stock had double this.
The major problem is that the rod ratio that these engines have mean they respond to duration more then overlap. So in effect you have either a JDM FS with higher compression and a intake cam that will make it more likely for you to zoom zoom boom, due to higher dynamic compression. As well as producing less power or an FP with a FS exhaust cam. Which is just sily as you want the FS intake cam and the FP exhaust cam as that would combine to give you 11 degrees overlap.
Should note that all these numbers are at .003 which means that your effective overlap is actually bugger all for USDM FS and your JDM FS.
