To VVT or not?
 

I currently have a perfectly smooth running 94R with 130k miles. My power goals are 200-250hp from a BEGI shanghai setup. Engine management will be a DIYPNP with 460cc injectors. This will be my first turbo.

I also have a VVT engine with 35k miles.

1) Is it worth it to swap in the VVT engine when my 1.8 can easily handle my goals?

2) If I decide to swap in the VVT, will a 94-95 shanghai kit still work on my car? Would I need a different DP/turbo manifold?

Thanks in advance.

You'll want something to control VVT or just have it set to full retard. You'll still see the higher rpm gains but lose mid-range with VVT set to full retard.

I believe the new MSIII will be able to control VVT, but don't hold me to it, heh.
But the ones that will are : AEM, Adaptronic(?), Haltech, Hydra, Xede, and thats all I know of lol.

If you have a means to control it you would be stupid not to utilize it.

Since I already have a DIYPNP, I am looking forward to the DIY VVT control unit. I heard that even at full retard, the VVT engine is still faster than my 94 1.8 because of the increased compression, better flowing head, and the full retard is actually 12.5 degrees so that's actually more base timing than my current engine anyways.

But the dilemma is that both will be reliable at 200 whp. The VVT would be more complex for me to install since I am a turbo noob. Should I swap the engine just to make about the same HP?

They say 94-95 blocks are stronger. When I say they I mean random threads on m.net.

But FWIW the 94-95 blocks have the pre-tapped hole for oil feed in a very convenient place, on the exhaust side near where the heater hoses are.

not worth it

Why not put the 01 head on the 94 block?

--Ian

From a cost/simplistic approach, you'll make your goals on the engine you have in there now. VVT won't hurt you, but to properly control it is going to be the key factor. Yes, the 01+ block has 10:1 compression which helps with off-boost power and throttle response and you may make a small gain by swapping in the 01+ block. Or you could throw the whole VVT engine in, forget about controlling the VVT for now, make a good base tune and hold out for the proper ECU to run the VVT. Remember that your current harness has no provision for the VVT solenoid and you'll have to add that yourself if you get a VVT enabled ECU.

If I were you and wanted to be impatient, I'd just skip the 01+ engine and boost what you have.

Your car currently runs fine, just leave it alone and put the turbo setup on it.

Didnt that stop with the 94 models??

You don't need it, but it would be a wicked street setup (10:1 + 2554R). Not a ton of torque, but all of it everywhere.

The VVT motor has the potential to run stronger than the non-VVT motor, if you want to deal with the extra cost/hassle of dealing with it.

VVT control *is* coming... ;)

believe me I've pondered this. if I make full boost at 3700 with the big mother of a turbo and VVT optimized... what kind of crazy low end would I have with a 2554....

does a 2554 CHRA fit in a GT2876 hotside housing?

wtfs? im sure the chras are identical. Its only the compressor, turbine, and housings that are completely different.

you can't replace the wheels on the GT28XX turbos. you buy the CHRA.

Oh your right, stopped in 94.



This sounds fun, I've got an extra 01 motor atm that I could use with my 99-00 head. All I need is the hotside parts! 230ft-lbs on a wide range of rpms would be pleasing :)

Where is the oil feed location on 01 blocks, same as a 95-97 block? Beside the oil filter?

Putting on the 99-00 head would completely remove the added effect of VVT....you would no longer have a broad tq curve.

Ok so it seems like the consensus is to turbo my stock engine.

Let's say I decide to go VVT next year, would the manifold/turbo/downpipe still fit on the VVT engine? Keep in mind I will be running a shanghai-S

I don't know dude, I'm pro VVT...

https://www.miataturbo.net/forum/t43108/

Everything on the exhaust side of the head is interchangeable between all of the 1.8L engines.