SP or SE

Garry · Postby **Garry** » Fri Apr 21, 2006 9:52 am

Rumour has it the SE engine is based on the engine from one of the 323 turbo motors with tougher crank shaft and connecting rods or bigger bearings or some such. Which explains it's lack of SVT, lower compression and lower redline. It's not the same engine as a regular MX5.

They probably needed to use up some old stock after the 323 went out of production.

jolt · Postby **jolt** » Fri Apr 21, 2006 10:13 am

Casey: Which begs the question - wouldn't it have been cheaper to build up a SP replica like Brian and Pilsner from a wreck/cheap import NB8B rather then build an SP replica from a SE?

Once again I say ... so how are you going to tune the SP?

Whereas there's a number of proven ECU/piggyback/interceptor options available to you for the SE at very reasonable purchase prices and are easily tuned all because it doesn't have S-VT.

That's why starting with the SE is easier and you get stronger gearbox internals.

Rod

sabretooth · Postby **sabretooth** » Fri Apr 21, 2006 10:20 am

What, the gearboxes are stronger too?

Garry · Postby **Garry** » Fri Apr 21, 2006 11:26 am

The SE gears have been shot peened to reduce manufacturing stresses. The rest of the gearbox is the same.

CT · Postby CT » Fri Apr 21, 2006 12:04 pm

Casey wrote:Which begs the question - wouldn't it have been cheaper to build up a SP replica like Brian and Pilsner from a wreck/cheap import NB8B rather then build an SP replica from a SE?

I am not building a replica SP though, I am building a real SE. Which means greater eligibility for events like Targa for example should I choose to prepare it that way. Replica's are not eligible for some events.(Prod sports will allow me to run it as an SP replica if I so choose - not sure I need to but it's an option). A replica might be cheaper but then it's only a replica.

Postby **Boyracer** » Fri Apr 21, 2006 12:24 pm

Body braces...I am pretty sure the SE has an extra brace...I don't remeber seeing this on a NB8B(NB8B owners would have to confirm this one)...it is the one on in the photo behind the heat shield,which the NB8B doesn't have.

Casey...Brians car was built up from a Aussie road car,not a wreck/cheap import.

CT..you would have to run the SVT engine to make the SE in to a SP replica.

I like the SE so much I bought 2 of them...

:lol:

rjastra2 · Postby **rjastra2** » Fri Apr 21, 2006 2:36 pm

Whereas there's a number of proven ECU/piggyback/interceptor options available to you for the SE at very reasonable purchase prices and are easily tuned all because it doesn't have S-VT.

Why is the SVT so hard to \"tune\"? Numerous other performance vehicles have VVT (VAG ubiquitous 20V 1.8L turbo for example) and are catered for by aftermarket tuners.

Surely piggyback ecus, aftermarket computers have outputs for the controlling of VVT. The issue is getting someone to \"tune\" it. This is then just a matter of $$$.

Garry · Postby **Garry** » Fri Apr 21, 2006 3:46 pm

BR,

The NB8B+ has all those braces except the silver heatshield thing

Casey · Postby **Casey** » Fri Apr 21, 2006 7:56 pm

Garry wrote:Rumour has it the SE engine is based on the engine from one of the 323 turbo motors with tougher crank shaft and connecting rods or bigger bearings or some such. Which explains it's lack of SVT, lower compression and lower redline. It's not the same engine as a regular MX5.

They probably needed to use up some old stock after the 323 went out of production.

That's true, it is a detuned version of the old Familia GTX engine (much smaller turbo though and certainly not the same spec as the GTR 180odd kW version

)

However, since the 1.8l GTX/GTR Familia (BP engine), all BPs used the MX-5 rods which superceeded the B6 GTX rods (which were actually beefier).

Also - the GTX Familia had oil sprays for the pistons and additional webbing in the block (the NA Familia B6/BP did not), however its been a long held belief that ALL MX5s use the extra stong GTX block with the oil sprays - although I have never seen this proven beyond all doubt. Maybe some of the racers/engine builders can prove/disprove this for once and for all.

So in short - I doubt that unless Mazda reproduced the 1.6l GTX rods especially for the SE, there is no difference in the engines aside from the out of date (in terms of modern day turbo thinking) lowered compression and lack of SVT.

Casey · Postby **Casey** » Fri Apr 21, 2006 10:14 pm

Boyracer wrote:I like the SE so much I bought 2 of them...

So did you vote twice? C'mon, the SE needs you (SP 52% vs SE 47%) :mrgreen:

Russellb · Postby **Russellb** » Fri Apr 21, 2006 11:17 pm

Casey . Batman's B6 has oil sprayer as a standed and so does Greenmachine's engine from the Open heart Surgey on both engines I would say they all do

O and Pilsners engine has them too
I hope when my engine come apart I find them in there too

Do you reconise this Casey?
:shock:

GRRRRR

Russellb · Postby **Russellb** » Fri Apr 21, 2006 11:22 pm

All so the VVT on the SP is worth nothing :shock:

it is just extra weight and completacty to an engine that can prduce a heap of power on the right tune

Casey · Postby **Casey** » Sat Apr 22, 2006 12:17 am

Russellb wrote:Casey . Batman's B6 has oil sprayer as a standed and so does Greenmachine's engine from the Open heart Surgey on both engines I would say they all do O and Pilsners engine has them too
I hope when my engine come apart I find them in there too

Do you reconise this Casey?
GRRRRR

How about the extra webbing in the block?

That's a nice turbo :mrgreen:

Garry · Postby **Garry** » Sat Apr 22, 2006 12:53 am

How much end play is there supposed to be in the turbo shaft in an SP?

Casey · Postby **Casey** » Sat Apr 22, 2006 1:08 am

Pilsner has a brand new one straight from Garrett for his SP replica and there is end play - less then 1/4mm I would guess. A lot more side play - probably 1/2-1mm.