The build begins

So hello folks,

I first fell in love with speeds 2 years ago when I bought my 13' red genpu, loved that car but it had a bad motor and whole bunch of issues that led to me selling it

I bought a 10' white genpu last summer, it has 225k km but had rebuilt oem spec engine put in around 200k

so for some back story I just recently added a DM 3.5" intake, DM RMM, DM EGR delete, UR test pipe and of course auto tech internals
As I was disassembling the car to install mods I noticed quite a bit of oil all along the intake tract, before I added mods compression was 180-180-160-170 so nothing too concerning but recently did a leak down test and got 9% for 1,2,4 but 3 had 9% at BDC and like 25% at TDC. We put a scope in there and found a straight line down the wall that was shiny so conclusion is too much blow by caused by the cylinder being scored

So now the fun part, I'm thinking of going built motor (550whp capable) with either a BNR S4 or cst4 and the rest of the supporting mods

For those of you with built motors how did u help justify the cost and what setups did you choose

 

Well mine was still my DD at the time and I always thought I would move into something "faster" when the Speed was done.

The used car market was completely fucked a couple years ago. I was looking at paying insane "market adjustments" on anything I would have been interested in.

Everything I was interested in was around 40k and dealers were wanting an additional 10k on top of that. So I said I'll just put the 10k into the Speed and have something faster and more fun.

I always wanted to pull a motor and do the whole "racecar" thing but was never really in a good situation to do it. This was my chance so I went ahead and did it and I'm glad I did it's been a lot of fun.

That being said I did have a plan to get a new DD and I don't think it's the best idea to DD a built motor. I did DD mine for the first year and put about 14k miles on it without any problems. Built motors just don't have the service life of an OEM motor and as you know are pretty expensive to build.

The Speed gets driven about 3-4k miles a year now and only come out when the roads are dry.

It's a hobby at this point and I just keep going further and further with parts and spending money on it. Financially it's not reasonable but what hobby is? Having fun and learning costs money sometimes!

 

I would probably DD it for the first year as well, when u say the service life, the motor should last as long as it’s maintained right and not being beat on all the time

 

When you go built motor there are a lot more variables introduced than when OEM builds the motor. Built motors have a higher instance of failure than OEM as a general rule.

You are putting a lot of faith in your machine shop and whoever assembles the motor to do things correctly. The actual process isn't overly complicated it's more that A LOT of attention to detail is required. Any short cuts or mistakes can have a direct impact on how long the motor lasts.

Take a look through some of the build threads here and you'll see more than a few people who are active here have lost a built motor. It happens it's part of the game.

That being said you can get some great life out of a built engine if it's put together correctly and taken care of. I'm not trying to scare you away from going built but you should be aware of the risks.

I actually talked to Jordan from Overspeed when I was debating on what I was going to do. He was a big fan of using the OEM long block from Mazda provided HP goals were modest.

 

The decision to build a motor is daunting for schleps like me. Out of my element for 30 years. More work than an air-cooled motor.

Biggest advice I have is to skim the block and head to remove warpage. Get the #s of material removed and get a Cometic gasket in proper spec. A valve job would be good at the same time. I was bored and honed 20 over. Oem vvt, swap wearable items like water pumps when in there.

Internals I got Manley HBeams and their pistons. Because I'm not going stupid power, a ton of oem was used too.

Don't wanna do the work or get one that is done? There are a few shops to use.

 

I’m going with Beltec performance we’re gonna work out the price but I’m going with him he’s built many engines and is starting to pick up. The engine in my car now was built by him and ran great and the issue with it isn’t his fault.
I’m confident it’ll be a solid motor and of course will be prepared for the worst

it’s gonna b a 550+ hp build so basically just forged rods and pistons with upgraded bearings and other upgrades as well as changing a lot of the stock parts

I was thinking of the bnr s4, but I was told an s5 or cst5 would be the better choice

my goal for the car is maxing out stock fueling this year and then aux fuel next year so I won’t be making more then 340whp this year and then eventually up to 500whp

the stock manifold is concerning with the unequal flow so I want to upgrade but I wanted to stay tmic so have to look into my options for that

 

I have CorkSport manifolds and very happy with them. And Beltec is good too. There are Canadian CS distributors too. I can be CorkSport fanboi because I have one of their 1st CST4 turbos and still cooking after 70k

 

I saw some flow tests for all the different manifolds on the forum I forget who posted it but the FoSt manifold is the best for equal flow I just don’t know how much having unequal flow really affects things
As for corksport I don’t have any experience with any of their products but I’ve heard nothing but good things

 

Yes oss Motorsport in Winnipeg is a Canadian corksport distributer, however it's generally cheaper to order from CS directly especially if oss then has to ship to you. Heck I know locals to oss that still just buy directly from CS.

Corksport manifolds are probably the way to go. If you're going built engine please don't use stock manifolds or stock flange turbo.

Also imo when it comes to turbo bnr > CS. Really tho if you're buying manifolds you can get a vband pte or pulsar turbo or even Garret.

 

My plan is to max out stock fuel until next year, I want an st manifold as they flow the most equal compared to any other manifold we have available
As for stock flange turbo you mean bnrs and cst right? I was thinking bnrs5 or cst5 but im not set on anything
Will stock EM damage the engine?

im only 19 im already spending close to 16k for the engine, dp (not sure wether to get catted or catless), ic, turbo, clutch+flywheel (probably going act 6 puck and streetlight), damond trilogy, injectors serviced and seals, oil gauges, and wtvr other miscellaneous things needed.

 

Why s5 vs cst5 they're not even similar sized that's like comparing the s4 to the cst4 they do not align.
What's your use case do you just want Dyno numbers? Drag? Roll race? Back roads? Lapping? All changes turbo selection

 

Don't really care too much about dyno numbers, roll races and back roads will be the main use.

Is the s5 more comparable to the cst6 or even that's not a comparison?

 

As Awa mentioned you need to have some goals in mind with turbo selection and HP goals/ intended use. Cars that run big turbos behave differently than cars with smaller frame turbos.

The guys making north of 600 whp def have a different experience than turbos that spool faster. That is unless you run something a bit exotic like an EFR or Garrett G series but both of those turbos require a lot of custom work to run.

There is def a balance to achieve for a street car between max HP and a fat power band. Cars that have a narrow power band aren't as much fun on the street. Also at a point it gets to be a bit unusable on the street as you have something so fast you can't really drive it fast on the street.

The old adage it's more fun to drive a slow car fast than a fast car slow holds true. That doesn't mean you can't have a fast speed but you need to think about how you want to use it.

What's your build going to be based around for HP capability? A BNR S4 can hit around 500whp on E mix and have a nice power band.

 

my engine can handle 550, if I want more I can add headstuds and get to 650+, but like u said I want it as a street car and at certain point its unusable, my goal is right around 500
I don't have access to E85 so that limits me a lot, Pump gas can get me to 500 with a 8th port setup with a standalone fuel cell that I can add some 94 and meth into for cooling
So from what I've read I need a bigger turbo then typical builds because of the pump gas restriction, which is why I was thinking bnrs5 but I emailed will from PD to get a better understanding of what he thinks ill need

Besides that I'm trying to get the most efficient setup for drivability and reliability, this is definitely a slippery slope and I don't want to buy parts twice

 

Turbocharging isnt about just adding a bigger turbo because you dont have the right type of fuel. You can do that, but it only works within a window. Choosing the right turbo for your requirements is all about efficiency. The right turbo will blow the doors off a wrong one.
Here are some videos Will @ PD made and @Sho graciously posted for us. These are gold and if you havent enjoyed them, I would start with watching them...
https://mazdaspeeds.org/index.php?threads/will-dawson-pd-tuning-educational-videos.8834/https://mazdaspeeds.org/index.php?threads/will-dawson-pd-tuning-educational-videos.8834/

 

OP there's a video in that series specifically about turbo selection. Will talks about all the popular bolt on turbos for the Speed and the HP they are capable of as well as spool characteristics.

All the videos are worth watching, they will answer some of your questions and give you a better understanding of the platform overall.

 

Dude wants 8 port and meth but doesn't want an exhaust manifold smh. I'm out.

 

I have watched those videos and am re watching them, that's where I saw him and I think nishan say that pump fuel requires a bigger turbo then having e85
This whole thread has gone in the wrong direction though I was mainly asking about your setups mainly those of you with 500whp and what mods you have, I still need to figure out what im going with before talking about it and sounding uneducated

 

In all fairness Awa he asked if the stock EM would damage the engine. I don't see where he said he didn't want one?

I do agree with you though if you are going to put all this work into a motor/turbo setup you really should do both IM and EM.

 

I 100% will, just don't know if ill do it right away, I found a guy selling a full race EM, 3" TBE, gtx3076r, pi kit all used with 5000km within 80km of me so I think its a no brainer to buy his setup