rabbit640

Looking for best balance of power and mpg. Searched everywhere and I am slowly starting to piece this together. So far it sounds like y5 with turbo will get about 35-40 mpg combined. The horsepower compared to z1 is better 125-175. The z1 has better mpg at 45-55 combined. The horsepower suffers at 92.

Obviously how you drive would effect mpg the most. I commute all over town (many times from opposite sides) hopping off and on I-80 trying to merge over in time to make it to the expressway or 680/480 interchange. Needless to say cruising at 50 mph lean burn is not always a reality for me. Should I go with the y5 turbo? Anyone with a z1 have trouble with interstate on ramps, passing, or any other scenarios where driving like a grandma is simply not possible?

I'm wondering if the y5 is more practical for my occasional aggressive driving. The 60+ mpg sounds great with the z1, but I don't think its a reality for me. My fear: getting the z1 -> getting 35 mpg due to aggressive driving -> realizing that I could get equal to that or greater with a y5 stock -> then realizing that with a turbo it could be even better ->

Also, this is my first post. Be gentle...

JuggerNaut-CTR

So is the real question turbo y5 or turbo z1? ...turbo y5 or n/a z1? Which one?

Theres a thread on here somewhere of a turbo y5 that made around 330whp and gets around 50mpg. I'll look for it in a sec

rabbit640

I read that the z1 doesn't really benefit from a turbo. Not 100% sure why. Consensus seemed to be that the z1 was too small (valves I think). The only successful turbo z1's I could find weren't truly z1 once the all the mods were done. Engine was much closer to a y5.

Question is definitely z1 vs turbo y5. I'm definitely leaning towards the y5. More reading is needed, but it sounds like the z1 is so weak it might not even be able to handle occasional aggressive driving. It's been described as "painfully weak" and interstate is a nightmare (especially on-ramps and aggressive merging). Any VX owners confirm this? Or stock z1 owners?

aaronhume

I drive a JDM version of the D15Z1 in my sedan all the time, it has much better torque than my old engine, I have it combined with my old tranny (94 civic sedan) and I have towed a boat with it... top end power is pretty much useless but I have no issues accelerating onto the freeway.