Anyone done a 99 head swap?

[sabretooth]

After discovering that I had in fact thrown away my original set of lifters, I'm now reconsidering my options. One thing that has come to mind is to use a 99 head on the block that I'm rebuilding (with forged pistons and whatnot). A new head would negate the need for lifters and will also buy me a performance boost at the same time.

Has anyone else done the swap?

[JBT]

Will you also need the 99 intake manifold to get the most out of it?

[JBT]

Have you done a price comparison between KIA HLAs (aren't they considerably cheaper than Mazda?) and a 99 head and stuff?

[Garry]

You'll need the 99 cams as well. The profiles are different for HLA's and solid lifters.

[Boyracer]

How much is a second hand set of HLA lifters worth?

I have a set sitting in the shed....would be prepared to part with them now I'm not a NA owner any more.

[sabretooth]

Yup, I know. I'll be getting a complete head.

JBT: They're half the price from Kia, but $20 (which is what I assume they are - I haven't confirmed) - multiplied by 16 = $320. So, a 99 head swap might just be a viable option assuming I can get the complete head for around that. I have to also factor in that I need a few new valves as I toasted some and also put a couple in the Familia motor. So the costs are adding up.

[kitkat]

sabre, you have a pm

[93_Clubman]

keith tanner also recommends nb fuel rail in his write-up

[sabretooth]

Thanks kitkat.

I was over at MX-5 Plus today getting a couple of bits (new alternator pivot bolt and washer bottle #3 :p). He doesn't really have heads for sale, so I'll have to see what I can do there. I'm contemplating reusing the 94 head though. I'll see what happens there. Apparently if I use the 99 head, I'm going to need the 99 intake manifold also, as the intake ports are 10mm higher on the NB than the NA engines. If the exhaust ports are similarly raised then I may ditch the idea. We'll see.

I'll do more research on whether or not the head upgrade is worthwhile or not. It's something I can always do down the track, as removing the head isn't -that- difficult really.

93_Clubman: was that in his book?

[Boyracer]

NA8 exhaust will fit the NB engine.

I thought you would have trouble getting a 99 head..best you could do is get a complete engine.

[lowmiata]

Geoff, just sell your red car and get a blue one!
Blue ones are alot less trouble if you leave the fuckers alone and don't modify anything!

No amount of head swaping, motor swapping bits and pieces adding will ever make it go as well as a blue one!

Please don't look at this post for anything useful to the above conversation!

[sabretooth]

NA8 exhaust will fit the NB engine.

I thought you would have trouble getting a 99 head..best you could do is get a complete engine.

Oh, thanks. In that case, a 99 head with intake manifold should do the trick. Actually, would an NB VVT head work? I don't really care for the VVT, but if it can fit then I'd use it. I guess the other concern is, did the NB8B use coil over plug?


Pfft, yeah right Ryan. You're in denial! How is the blue beast going, anyway?

[CT]

Hey Sabre, I think the head swap would be a waste on your turbo motor. I'd just fork out for the new HLAs. On a high revving NA race spec motor it would certainly be worth it. My highly modded early head flows about the same as a mildly ported late head. Had I started with a late head, flow rates above 260 net hp would be possible.

[93_Clubman]

93_Clubman: was that in his book?

sure was sabre - pages 45-46 - let me know if you need them. ref vvt engines, tanner reckons 1999-2000 (us) cars are the best choice for swapping from as with vvt you somehow need to control it. he also reckons the head, intake manifold & intake cam are physically different on vvt engines...