'95 1.8 in a '99?
#7
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I know it's inferior. But this head has been ported and polished with a 3 angle valve job, so it flows a little better than the factory '95 head. The other main issue I'm having would be paying $2,700 for basically a short block if I use the '99 head. If it comes down to it, I will use it. But if it works with the '95 head, I'd do that too. All I was wanting to know is if it would work or not.
#10
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I have a 99 motor in my 95 and it a considerable change. Your main issue, if you want to use the earlier head, is going to be making all the connection correspondent to the 99 wiring. Also the 99 does not use a CAS as the 1.8 do. You would have to eliminate the CAS (which you can donate to me, I am in need of one) block cavity that it leaves and use the crank position sensor from the 99. Aside from that everything else is pretty much the same.
#12
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You can simply drop in the 95 engine.
Then... speaking from memory here. I'm assuming you're using a stock ECU.
You will need to use the 94-97 intake manifold with 99 throttle body. It will bolt up, the throttle cable should fit too. Then, use the camshaft gears and valve cover from your 99 head. That will allow you to re-use the cas-on-valvecover sensor. All NBs have a crankshaft sensor. The 95 block SHOULD have a threaded hole for that sensor, so it will bolt up. The hole may be hard to see due to grime/dirt whatever. For the crankshaft sensor to work, you'll need to use the crankshaft pulley boss and timing plate from your 99 engine. Finally, use your old coil pack.
This will get the car running but it'll throw a ton of engine codes due to disconnected VICS and EGR. Also the EGR crossover pipe from 95 exhaust manifold will probably not bolt up to the 95 intake manifold. You could use a 99 exhaust manifold, but then you need pretty much the whole exhaust as well. And the 99 exhaust manifold sucks!
edit: the coolant temperature sensors on the back of the head might also be different, so check if connectors fit before you swap. If they don't fit you can swap the whole rear water neck.
edit edit: you WILL need to do something about the fuel rail. 99 fuel rail is returnless (one hose), 94-97 is a return system (2 hose). There's a good guide explaining what you need to do to change from returnless to return (http://www.mx5atlanta.com/forums/showthread.php?t=13121). You will need to do the opposite, I guess? Don't really know.
Then... speaking from memory here. I'm assuming you're using a stock ECU.
You will need to use the 94-97 intake manifold with 99 throttle body. It will bolt up, the throttle cable should fit too. Then, use the camshaft gears and valve cover from your 99 head. That will allow you to re-use the cas-on-valvecover sensor. All NBs have a crankshaft sensor. The 95 block SHOULD have a threaded hole for that sensor, so it will bolt up. The hole may be hard to see due to grime/dirt whatever. For the crankshaft sensor to work, you'll need to use the crankshaft pulley boss and timing plate from your 99 engine. Finally, use your old coil pack.
This will get the car running but it'll throw a ton of engine codes due to disconnected VICS and EGR. Also the EGR crossover pipe from 95 exhaust manifold will probably not bolt up to the 95 intake manifold. You could use a 99 exhaust manifold, but then you need pretty much the whole exhaust as well. And the 99 exhaust manifold sucks!
edit: the coolant temperature sensors on the back of the head might also be different, so check if connectors fit before you swap. If they don't fit you can swap the whole rear water neck.
edit edit: you WILL need to do something about the fuel rail. 99 fuel rail is returnless (one hose), 94-97 is a return system (2 hose). There's a good guide explaining what you need to do to change from returnless to return (http://www.mx5atlanta.com/forums/showthread.php?t=13121). You will need to do the opposite, I guess? Don't really know.
#13
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I know it's inferior. But this head has been ported and polished with a 3 angle valve job, so it flows a little better than the factory '95 head. The other main issue I'm having would be paying $2,700 for basically a short block if I use the '99 head. If it comes down to it, I will use it. But if it works with the '95 head, I'd do that too. All I was wanting to know is if it would work or not.
#19
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Well, two years later and still no boost. :( just finished my BP4W head and am building a custom intake manifold. After everything checks out, I'll be going with an FMII with a 3071. Things were on hold for a while, and I've just been putting miles on it.
The NA 1.8 actually worked very well in the car, and was rather painless to swap, in case anyone was wondering. It was pretty slow though. Low compression pistons (and what turned out being a STOCK NA 1.8 head with a gasket match) definitely did not help. Would not recommend doing it lol.
The NA 1.8 actually worked very well in the car, and was rather painless to swap, in case anyone was wondering. It was pretty slow though. Low compression pistons (and what turned out being a STOCK NA 1.8 head with a gasket match) definitely did not help. Would not recommend doing it lol.