Bullet Ride's 2.8L Stroker Project (Updated: Dyno Plot pg. 6)

[acolella76]

Looking great! I dig that valve cover.

On a scale of 1-10 how hard would you say building a MS box is? I haven't decided if I want to buy a premade box or build my own.

[Kershaw]

looks great man! really good stuff.

one reason why rougher surfaces flow better is the same reason a golf ball has dimples. the rough surface traps air onto it and creates an air to air boundary layer. the flowing air flows over the trapped air a lot easier than the metal.

[BergerNJ]

that valve cover looks awesome.

[Bullet Ride]

Small update

This arrived in the mail yesterday...




Building...and yes I used Jenga blocks to prop up the board while I was inserting the components with the long leads. Then I put that piece of Styrofoam from a ground beef package on top to hold the components in place while I flipped the board over. Then I soldered and trimmed the leads. A good bit of precision engineering really...



Between last night and this evening I got the kit built, I just need to get some vacuum line for the map sensor, load the firmware and maps and then (hopefully) fire up the car and get it running well on the kit ahead of time.



I also buffed the valve cover today, I'm happy with the way it turned out...



My mom would probably tell me I need to iron my valve cover...

[CabbE30]

Me limey whats going on here

[Simple_Smith]

Nice work so far can't wait to see the finished valve cover

[Bullet Ride]

I went out this morning to check on my wrinkle...

Oh how sweet the wrinkle is...




Things are starting to come together, I can't wait to start assembling this thing...

[Bullet Ride]

I painted the block and valve cover this afternoon. I used VHT low gloss black engine enamel for the block and VHT wrinkle red (Ferrari stlye :pimp:) for the valve cover

Block scrubbed and wiped down...



After first coat...



After final coat...





This was right after I sprayed the valve cover, I'll have to wait a few hours to see how the wrinkle turns out. Once it's cured I'm going to sand the paint off the raised parts of the valve cover to give it a nice machined aluminum look...



All the parts I need to start assembling the motor have been ordered. I hope to have them within the next couple weeks.

[Bullet Ride]

Small update

I picked up the crank and flywheel from balancing on Friday.
Here is the flywheel and pressure plate. They didn't need too much. You can see a little bit was ground off the edge of the pressure plate and there's one small hole that was drilled into the flywheel.



Here's the crank...



This is what the one end took...



This is what the other end took...



Looking back on when I was machining the crank, when I put the chamfers on the counterweights I just did it by eye because I figured it was just for added clearance and wasn't that critical. However in retrospect I should have measured and made sure all the chamfers were equal because in the end it affects the balance of the crank.

I also got the lasercut for the cam gear however it still needs to be machined.

[Bullet Ride]

Since I don't have gaskets, I haven't looked to see yet whether the port on the intake manifold is smaller or larger than the port on the head. So that in and of it self will be a deciding factor in what I end up doing. But since the intake runner is essentially a nozzle, opening up the front edge just to match the gasket won't hurt the velocity of the flow. It might affect the atomization as you mentioned, but in a fuel injected car it's not really an issue.

One of the things I've noticed about the guys flow testing heads is that they usually just flow test the head without any consideration of what's going on before the head. You can have a head that flows great, but if your intake runner is the diameter of a McDonald's straw the system as a whole is going to flow poorly. Intake runner geometry is a whole other ball game that I'll have to get into when I attempt to build an ITB set-up for this thing...

[The Humjet]

Your last statement you wrote about not polishing the intake is mostly true. The rough finish helps prevent fuel fallout. In the olden days hot rodders used to leave a lip between the manifold and port entry because the fuel would come in and be kicked up over the lip thus helping the fuel to enter the chambers in a vapour form (which is good). At the time they didn't know why the engines were making more power they just thought it was one of Gods many miracles.
On a race engine were everything in the motor is fine tuned to extract every bit of power then polishing heads will further improve power figures. But on your engine or any other street motor we see on this site then a rough finish is the way to go.
But then again your probably better off leaving it alone just because you already have that lip from factory and maybe a gasket match could make it worse if your not porting other areas of the intake ports.

[Bullet Ride]

so youre not going to port your intake side? you say it worsens the flow...what do you mean?

just trying to learn here.....I read every stroker thread I can

I'm only going to gasket match it and that's it because I don't know enough about how to modify the port geometry to improve the flow and I don't have access to a flow bench. If you start messing around with the intake side you can do more harm then good pretty quickly if you don't know what you are doing, and without a flow bench to test there's really no point in trying. The one thing I know for sure is that polishing the intake ports is a mistake because you actually want that little bit of roughness to help promote turbulent flow so that fuel and air will mix. A smooth port will give you high velocities but poor atomization of the fuel, that's why it's ok to polish the exhaust side because all you care about at that point is getting the exhaust gasses out as fast as possible. This thread has some good information http://www.e30tech.com/forum/showthread.php?t=55675

[BergerNJ]

so youre not going to port your intake side? you say it worsens the flow...what do you mean?

just trying to learn here.....I read every stroker thread I can

[dude8383]

The mediation pic had me rolling. Enjoying the step by step progress really allows everyone to visualize whats involved.

I want to build a 2.8 stroker as well but sometime in the future. Will definitely be referring back to this for guidance!!!

[Bullet Ride]

Good to see you on the machines doing it yourself. Hope it all goes well for you.
Just curious on what you do for a living. It's good to see you teaching and going over the processes undertaken when machining these parts which makes it an interesting read the few of us who aren't in the trade.
My guess would be your a fitter and turner of some sort.

For a living, currently I'm a mechanical designer for a small company that makes special purpose lifting equipment. I received my degree in mechanical engineering last year and just started working this past December. Unfortunately they don't teach you how to run machines as part of the degree requirements. The machining experience comes from the two summers I worked in a machine shop while I was in high school.

Couple of things about this thread that made me, as an Aussie, smile:

- you use the term "in the bush"

- your picture of snow coverage is "one of the not so cold days"

I am now subscribed and looking forward to how this goes. Keep on with the great pics and narrative

Cheers mate :up: