Building a Race Car. The great engine debate.

[Sh0velMan]

Okay a friend of mine is building a race car.

He's starting with an S13 240SX chassis and is researching a powerplant and driveline for it.

We want to avoid cliche like the SR swap and to a lesser degree, the RB and LS1 swap.

Here are the potentials being debated:

1) Ford 302 (5.0 roller cam, efi)
2) Mazda MZR 2.3 DISI Turbo
3) Ford Cosworth YB
4) Nissan VH45DE

Each has their merrits, I'll list them as we understand them:

1) Ford 302
- Parts everywhere, cheap.
- Tons of power and torque
- Easily attainable transmissions (Anything from a T-45 to a T-56 works)
- Even with a T-56 only 15 pounds heavier than the KA24DE coming out of the 240
- V8 sound
- Almost no one has done it
- Durable

2) Mazda MZR DISI Turbo (my favorite)
- POWER
- Lightweight compared to other choices
- Hightly Upgradable and Tunable
- Accepts NC Miata transmissions (2006+)
- NEW(ish), the only engine still being used in a production vehicle
- Durable
- Unique. No one has done it, to my knowledge

3) Ford Cosworth YB
- POWER
- Lighter than the V8 options
- Highly respected, lots of development, lots of real race-ready parts
- Durable
- Unique. No one has done it, to my knowledge

4) Nissan VH45DE
- It's a freakin 4 cam V8.
- With some work, can easily do 350-400whp N/A
- Using an adapter, can work with the Z32 5 speed transmission
- V8 sound
- Rare, but not unheardof, so some adapter parts are available off the shelf.
- DURABLE, fully forged internals, real race-derived stuff built in, this is what the Super GT engines of the late 90's were based off of.

Okay now the negatives...

1) Ford 302
- Adds weight. Realistically probably around 30-40 pounds.
- The most custom work of any of the options (headers, exhaust, moving things reward for weight balance)
- It's an ancient, pushrod V8..
- Automatically puts you in any highest class if classed by displacement.


2) Mazda MZR DISI Turbo (my favorite)
- Not a Nissan engine...?
- Finding a harness and ECU a challenge.
- Uncharted territory mounting to a RWD tranny, some development needed
- There aren't tons of doner cars yet, but the car is still in production.


3) Ford Cosworth YB
- The only incarnation of this engine sold in the US was the SOHC engine in the SVO Mustang and Merkur.
- Pretty much have to buy an expensive crate motor
- All parts will be shipped from Europe
- Only transmission choices are the SVO/Merkur or really rare models from a specific trim of Ford Sierra sold in Europe for a handful of years.
- A simple break could cause weeks of downtime due to availability of parts.

4) Nissan VH45DE
- Weight, it's the heaviest of the options.
- Rarity, only used in Inifinity SUVs in the US for a handful of years.
- Glass ceiling on power since it isn't forced induction and there aren't any aftermarket engine parts to speak of.
- Finding an ECU/Harness will be difficult.
- Automatically puts you in any highest class if classed by displacement.

================================================== ========

Okay. So, what do you guys think? My friend is romanced by the Ford Cosworth YB motor because he reads too much speed hunters (seems like two thirds of their coverage is in Europe where these engines are common, and mostly used in FWD/AWD cars).

He knows how awesome the MZR Turbo is, as he used to have a MS3, which I now own, but is insisting the YB could be just as great..

Am I crazy? Is an MZR with a Miata 6 speed a terrible choice?

[HKYStormFront]

there's a reason the LS based engines are the most common swaps... they are the easiest to swap and easiest to make boat loads of power. no matter what the guy wants to do, the LS swap is always going to be the best bet. also, a fully dressed LS probably isn't going to weigh much more than the KA you are taking out. they really are that light...

[M.Bonanni]

I understand the want to be different, but if you're going to actually race it the LS swap is the way to go. Replacement parts can be found at Auto Zone, there's a wealth of knowledge out there for them (even for LS swap S Chassis), they make awesome useable power, and it will be an easy swap. If your friend is going to competitively race it the last thing he should want is a race ended because he can't find a replacement part on the fly.

[cossie1600]

What class do you run in?

['10Anamoly]

2) Mazda MZR DISI Turbo (my favorite)
- POWER
- Lightweight compared to other choices
- Hightly Upgradable and Tunable
- Accepts NC Miata transmissions (2006+)
- NEW(ish), the only engine still being used in a production vehicle
- Durable
- Unique. No one has done it, to my knowledge

I wouldnt even consider the Mazda MZR if you plan on durability. They have significant journal bearing issues and the turbos tend to die frequently, even on stock boost. The PCV system is poorly designed and I've seen multiple folks with hydrolocked motors from oil backup, both with stock setups and more frequently with aftermarket turbos.

[HKYStormFront]

Originally Posted by '10Anamoly

I wouldnt even consider the Mazda MZR if you plan on durability. They have significant journal bearing issues and the turbos tend to die frequently, even on stock boost. The PCV system is poorly designed and I've seen multiple folks with hydrolocked motors from oil backup, both with stock setups and more frequently with aftermarket turbos.

not to mention mazda makes it pretty hard to modify the programming in the car, much less transplanting it into a different car. the D/I on that engine and the setup/time/research associated is enough of a minus, imo, to take it off this list.

[Marti]

I'm sorry dude but the LSx is the only way to go in this case. Simple to service, tons of pre-made swap parts are available and the performance is there.

[HKYStormFront]

this should be the goal:



i dunno if they are still around but the company advertised on the front of this car (Iceberg Customs) was working on a full bolt in swap kit for the S13/14

[Sh0velMan]

As far as MZR Reliability, I've got one that I've been around/driving since it was new in 2007, and have never had any issues... Scary to hear that others are having such severe problems. That's definitely off the table.

I personally love the idea of a LS2 or LS3, but my friend despises GM too strongly to even consider it.

Thanks for the input guys, he's probably just gonna do his stupid YB build. He'll regret it, but people are people, lmao.

[Jamielle@FP]

I like the idea of being different as far as the motor swap, but if you're going to be racing the car. The LSx motor honestly is your best bet, I'm building one with a friend right now and can tell you from experience its nice being able to go to the parts store and find any part I need right away without a hassle. Don't worry your friend will come around when he starts having to source parts and misses track days because he cant just go to the parts store to fix a problem.

As far as the MZR, it does have problems esp when you start beating on them in race conditions.

[Sh0velMan]

Originally Posted by Jamielle@FP

I like the idea of being different as far as the motor swap, but if you're going to be racing the car. The LSx motor honestly is your best bet, I'm building one with a friend right now and can tell you from experience its nice being able to go to the parts store and find any part I need right away without a hassle. Don't worry your friend will come around when he starts having to source parts and misses track days because he cant just go to the parts store to fix a problem.

As far as the MZR, it does have problems esp when you start beating on them in race conditions.

Yeah hope he does.

One day I could see myself swapping in one of the aluminum block LS motors (maybe an LS7?? ) into the Z when its engine has been wrung for every event it's got.

[DJ-of-E]

Is the race car built for competition use or just for fun? My mistakes when I built mines the first time is not deciding what class I am in. Next thing you know, I ended up with a class that costs too much and so much work for me to be any sort of competitive.

[Kingbaby]

I agree with the rest LSX!


or

HR or VHR

[Sh0velMan]

THanks for the input guys.

I hope he decides to go with one of the domestic V8's. Be it an LS or a SBF.

It'll cost more than a Hi-Po crate motor just to get an OEM YB motor over here from Europe... heh.