after engine swap .. RPMs skyrocket on ignition
#21
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I dont think it will be an issue once a new gasket is in place. I've seen gaskets that extrude into the ports, others that have a good 1/8" of clearance around it.
Thing about it this way: Imagine seals that only use o-rings, My Prelude's idle valve comes to mind. A simple o ring surrounds the air passage and once you mash the flanges together it creates a seal around it...but the material doesn't come close to extending out past the flanges.
The really important thing here is that you get a seal around the ports.
And like I posted on m.net, the part numbers for the 95-97 IM gasket are identical.
Also, the fact that there was a gap between the flanges suggests that you didn't tighten evenly/fully.
Thing about it this way: Imagine seals that only use o-rings, My Prelude's idle valve comes to mind. A simple o ring surrounds the air passage and once you mash the flanges together it creates a seal around it...but the material doesn't come close to extending out past the flanges.
The really important thing here is that you get a seal around the ports.
And like I posted on m.net, the part numbers for the 95-97 IM gasket are identical.
Also, the fact that there was a gap between the flanges suggests that you didn't tighten evenly/fully.
#22
I dont think it will be an issue once a new gasket is in place. I've seen gaskets that extrude into the ports, others that have a good 1/8" of clearance around it.
Thing about it this way: Imagine seals that only use o-rings, My Prelude's idle valve comes to mind. A simple o ring surrounds the air passage and once you mash the flanges together it creates a seal around it...but the material doesn't come close to extending out past the flanges.
The really important thing here is that you get a seal around the ports.
And like I posted on m.net, the part numbers for the 95-97 IM gasket are identical.
Also, the fact that there was a gap between the flanges suggests that you didn't tighten evenly/fully.
Thing about it this way: Imagine seals that only use o-rings, My Prelude's idle valve comes to mind. A simple o ring surrounds the air passage and once you mash the flanges together it creates a seal around it...but the material doesn't come close to extending out past the flanges.
The really important thing here is that you get a seal around the ports.
And like I posted on m.net, the part numbers for the 95-97 IM gasket are identical.
Also, the fact that there was a gap between the flanges suggests that you didn't tighten evenly/fully.
though it is funny .. that i wasn't getting any responses or help at all on m.net until i posted here! ha
#23
well .. hell .. interesting turn of events. i've been talking with brandon from flyin miata and he's been extremely helpful. he suggested that my alignment issues and whatnot could suggest that the head is not a 97 .. and in fact, a 99. He told me to check the back of the head and if it says BP4W.. then it's a 99. well .. go figure, that's what it says (picture)
this never even occurred to me as a possibility because I was told i bought a rebuilt 97 engine.. i guess now i actually bought a rebuilt 99 engine?!
so that's good and bad ....
bad, because this is not something i was prepared for and now have no idea what needs to be changed with my setup to make the engine work with the rest of my car!
with this new information .. what is necessary to get the car and engine compatible?
below is my list .. what else do i need to add?
-99 intake manifold
-99 intake manifold gasket
-something about an MSD RPM switch.. what's this?
-egr pipe compatible with 99 head and FMII turbo exhaust manifold
----assuming the one FM sent me with the 95 turbo kit is no longer compatible
-fuel feed rail.. my 95 one feels a bit tight
so .. what can i add or remove from this list?
what changes will i need to make within megasquirt to account for a different engine?
heeellppp!
thanks
EDIT: another thought .. since it's a 99 head ... does it mean the entire engine is a 99? does that make a big difference over a 95 or 97 engine? as far as compression or anything with the cylinders/crank?
this never even occurred to me as a possibility because I was told i bought a rebuilt 97 engine.. i guess now i actually bought a rebuilt 99 engine?!
so that's good and bad ....
bad, because this is not something i was prepared for and now have no idea what needs to be changed with my setup to make the engine work with the rest of my car!
with this new information .. what is necessary to get the car and engine compatible?
below is my list .. what else do i need to add?
-99 intake manifold
-99 intake manifold gasket
-something about an MSD RPM switch.. what's this?
-egr pipe compatible with 99 head and FMII turbo exhaust manifold
----assuming the one FM sent me with the 95 turbo kit is no longer compatible
-fuel feed rail.. my 95 one feels a bit tight
so .. what can i add or remove from this list?
what changes will i need to make within megasquirt to account for a different engine?
heeellppp!
thanks
EDIT: another thought .. since it's a 99 head ... does it mean the entire engine is a 99? does that make a big difference over a 95 or 97 engine? as far as compression or anything with the cylinders/crank?
#24
You could also use a 01-05 IM and remove the VTCS if you want a simple solution. Also finding a NB2 IM will be easier/cheaper. Either wal, you'll need a gasket (same from 99 to 05).
When you got the engine, was there a CAS on th eback of the head (exhaust cam)? Was there a valvecover with a sensor on the intake cam gear? That would have been a quick indication of the 99/00 engine. The pistons have 9.5:1 compression and shouldn't be much of a problem with boost (94-97 is 9:1).
NB fuel rails are returnless- you'll need to modify one for your retun line. Though I'm sure the NA fuel rail should be OK.
You should need a 99/00 EGR pipe. Ask FM if you can trade yours in? Or you can remove it- put a block-off plate on the IM and use a plug on the exhaust manifold (I used a drain plug for a 1998 Dodge Dakota Diesel).
When you got the engine, was there a CAS on th eback of the head (exhaust cam)? Was there a valvecover with a sensor on the intake cam gear? That would have been a quick indication of the 99/00 engine. The pistons have 9.5:1 compression and shouldn't be much of a problem with boost (94-97 is 9:1).
NB fuel rails are returnless- you'll need to modify one for your retun line. Though I'm sure the NA fuel rail should be OK.
You should need a 99/00 EGR pipe. Ask FM if you can trade yours in? Or you can remove it- put a block-off plate on the IM and use a plug on the exhaust manifold (I used a drain plug for a 1998 Dodge Dakota Diesel).
#25
You could also use a 01-05 IM and remove the VTCS if you want a simple solution. Also finding a NB2 IM will be easier/cheaper. Either wal, you'll need a gasket (same from 99 to 05).
When you got the engine, was there a CAS on th eback of the head (exhaust cam)? Was there a valvecover with a sensor on the intake cam gear? That would have been a quick indication of the 99/00 engine. The pistons have 9.5:1 compression and shouldn't be much of a problem with boost (94-97 is 9:1).
NB fuel rails are returnless- you'll need to modify one for your retun line. Though I'm sure the NA fuel rail should be OK.
You should need a 99/00 EGR pipe. Ask FM if you can trade yours in? Or you can remove it- put a block-off plate on the IM and use a plug on the exhaust manifold (I used a drain plug for a 1998 Dodge Dakota Diesel).
When you got the engine, was there a CAS on th eback of the head (exhaust cam)? Was there a valvecover with a sensor on the intake cam gear? That would have been a quick indication of the 99/00 engine. The pistons have 9.5:1 compression and shouldn't be much of a problem with boost (94-97 is 9:1).
NB fuel rails are returnless- you'll need to modify one for your retun line. Though I'm sure the NA fuel rail should be OK.
You should need a 99/00 EGR pipe. Ask FM if you can trade yours in? Or you can remove it- put a block-off plate on the IM and use a plug on the exhaust manifold (I used a drain plug for a 1998 Dodge Dakota Diesel).
when i picked up the rebuilt engine .. no cas, but the mounting place was there, but that's the same spot at my 95 cas... which fit without issue.
the valvecover has a hole for a intake cam sensor .. but no sensor installed... i just figured that was something for an OBDII requirement. speaking of that sensor hole .. do i need to plug it?
My NA fuel rail fits .. it just is a tight fit
#26
I finally checked up on this thread, upon seeing this photo
I was immediately going to chime in. This in indeed a '99+ head. That crosshatch casting pattern is unmistakeable.
The NA fuel rail won't fit. (Well, it will "fit", but because of the angle that you've forced the injectors to take, it won't work) You'll need the '99 fuel rail. Theres a damper of sorts bolted to the front end of the '99 fuel, unbolt it and the '95 FPR bolts to it. You'll need to bolt the FPR on upside down, simply run the fuel line back down between the #2/#3 intake runners.
The EGR pipe will be a tricky bastard. IIRC, the attachment at the exhaust header is different as well as the routing. This effectively means that you need a NB header to run EGR to an NB IM. Alternatively, I'm sure you could probably massage the NA EGR pipe to fit., but it will take some effort. I suspect that people that do the NB head swap generally block the EGR system. If you're using a flyin' miata turbo kit, you already have the NB EGR exhaust fitting in place, and you'll simply need a stock NB pipe.
I was immediately going to chime in. This in indeed a '99+ head. That crosshatch casting pattern is unmistakeable.
The NA fuel rail won't fit. (Well, it will "fit", but because of the angle that you've forced the injectors to take, it won't work) You'll need the '99 fuel rail. Theres a damper of sorts bolted to the front end of the '99 fuel, unbolt it and the '95 FPR bolts to it. You'll need to bolt the FPR on upside down, simply run the fuel line back down between the #2/#3 intake runners.
The EGR pipe will be a tricky bastard. IIRC, the attachment at the exhaust header is different as well as the routing. This effectively means that you need a NB header to run EGR to an NB IM. Alternatively, I'm sure you could probably massage the NA EGR pipe to fit., but it will take some effort. I suspect that people that do the NB head swap generally block the EGR system. If you're using a flyin' miata turbo kit, you already have the NB EGR exhaust fitting in place, and you'll simply need a stock NB pipe.
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