BUILD-OFF CHALLENGE: Tygaboy's '75 LS3, It seemed a good idea at the time... Options

[djway]

Don't be fuelish, it is very interesting. (IMG:style_emoticons/default/laugh.gif)

[Andyrew]

Looking good!!

[tygaboy]

HUGE thanks to Bob @BIGKAT_83 for personally driving these seats from GA to CA! Bob, it was great meeting you and your wife. Oh, and your pup, Henry, too!

These are the seats I purchased from @fasthonda . They are super nice and more supportive in the upper bolster area than the GT Classics LeMans seats I have. But now that I've seen then in my car, I'm not quite sure if I'm digging the look, compared to the LeMans', so the jury is still out on if I'll keep them.

If I do keep them, I'll likely have them redone in black with appropriately colored tartan inserts. I'm leaning toward the GTI tartan pictured.

But again, I can't thank Bob enough for making this happen. It's always great to meet another 914 World member in person, put face to name and shake hands with a new friend.

[Krieger]

I like the look of those seats. What makes them look odd is the padding on the aft section of the headrest. The GTI upholstery looks good too. Especially if you go blue on the exterior.

[djway]

They would look great with the other material (IMG:style_emoticons/default/smile.gif)

[Cairo94507]

Yeah, I like those too. Of course they need to be covered, but otherwise those look nice to my eyes. (IMG:style_emoticons/default/beerchug.gif)

[Andyrew]

I like the Tartan pattern!!

Those are Skinny boy seats for sure (IMG:style_emoticons/default/smile.gif)

I like the Lemans personally, but if you tartan up those Renegade seats I might like them more (IMG:style_emoticons/default/smile.gif).

[Curbandgutter]

I like the Le Mans seats more. Maybe, its the little medallion vents, (I don't know what they are called) that look classy. I'm leaning to getting the Recaros that were used on the Big Laguna car. I sat in them and was very pleased. I'm curious why are you even wanting to make a change from the Le Mans seats? Were they that bad?

[tygaboy]

I like the Le Mans seats more. Maybe, its the little medallion vents, (I don't know what they are called) that look classy. I'm leaning to getting the Recaros that were used on the Big Laguna car. I sat in them and was very pleased. I'm curious why are you even wanting to make a change from the Le Mans seats? Were they that bad?

@Curbandgutter Rudy - The LeMans seat are REALLY comfortable for 90% of the driving I expect to do. But they do seem a little "loose" on me in the upper body area when the cornering gets spirited.

I wanted to try something else so I bought the Renegades, figuring I could always sell them if I opted to stay with the LeMans. The jury is still out so no decisions until I've got some miles on them.

I will also say you sit noticeably higher in the Renegades vs the LeMans. I may start with having maybe 1/2 the padding taken out of the bottom cushion. We'll see.

[tygaboy]

Well. After mucking about with the throttle bodies, I'm going back to a stock LS3 intake manifold and a single drive-by-wire (DBW) throttle body.

Without going into too much detail, I've learned a LOT about these systems. Things like:
- very minor throttle openings (from idle) QUICKLY add air flow. This means you build a fuel map that looks at the TPS (throttle position sensor) in like 2% steps, up until about 20% open throttle
- from about 65% - 100% throttle, there's actually very little increase in air flow. My engine is getting all the air it needs at ~65% throttle! And let's be honest, in my case, it's not a race car so I spend virtually ALL my time at very low throttle openings
- in a light car, minor pedal movement, um... "makes things happen"

In short, ITBs, particularly my cable-driven version, make driving my car anywhere but the freeway, an experience that requires 100% attention. It's more mental work than I want to do. But please don't get me wrong. I LOVE these things. Just not how they currently work.

So for now, I'm moving to the stock intake. Of course, my Holley HP ECU doesn't support DBW so I'll be replacing the HP with a Holley Dominator ECU, building a new engine wiring harness and, as pictured, moving to a DBW throttle pedal. This is a stock Corvette pedal that I've chopped up and will connect to the Tilton throttle pedal with rod ends and an appropriate length rod.

Yes, the brake line needs to be moved - this is just initial fitting to determine linkage specs. I'll tidy it up once all the dimensions are known.

The good news is that the Dominator ECU can be used to alter how the throttle body responds to the pedal!
For example, if I want 10% pedal to only be 5% throttle body opening, I can do that.
This should make for a pedal that does exactly what I want and feels the way I want it to feel. Who-Ray. (IMG:style_emoticons/default/aktion035.gif)

Let this round of "doing things over" begin! (IMG:style_emoticons/default/lol-2.gif)

And fear not. I'm working with my tuner on converting the ITBs to DBW. It requires a bunch of custom stuff but what fun would it be if that wasn't the case? (IMG:style_emoticons/default/shades.gif)

[Cairo94507]

Hi Chris - Wow. I really love the look of the ITBs. But if they don't allow you to make the car drivable the way you want, then I understand the switch. It's not like you won't have tons of HP anyway. Hopefully in the next month or so I will get a chance to come over and BS with you. (IMG:style_emoticons/default/beerchug.gif)

[djway]

At least you don't need to cut the trunk....

[tygaboy]

Well. Clearly not as cool looking as ITBs, but not bad.

I did upgrade from the stock fuel rails to the Holley set you (sorta) see here. This to keep the same return-based fuel system plumbing I already have in place.

I have a few additional things in mind to try and recoup at least some style points. Let's see how I do.

[djway]

R2D2 could fit there and talk to all the electronics for ya (IMG:style_emoticons/default/wink.gif)

[tygaboy]

DBW mechanical connections all set. Really happy with how this turned out. There is ZERO slop or flex and the linkage ratio is adjustable over a pretty wide range so beyond being able to program how the throttle body responds to the pedal, I can also tune the physical pedal travel to feel just how I want it.

But maybe the best part is that red indicator toward the left end of the custom linkage bar. It's a shallow groove which was then colored red. Why? It's a visual reminder that it's the left-hand thread end. No more guessing which way to turn the jam nuts when adjustments are needed.

It's the little things... (IMG:style_emoticons/default/aktion035.gif)

[Mueller]

Those pedals look so cool and high tech. Bummer about the ITB's but in the end you do want to drive the car and not be on pins and needles and worrying about the throttle input.

[Chris914n6]

Now that you've done all that work....

you should be able to get a progressive pulley for the cable TB to numb the off-idle response.

[tygaboy]

Now that you've done all that work....

you should be able to get a progressive pulley for the cable TB to numb the off-idle response.

@Chris914n6 - If you check back in the build, you'll see I'd already done that. See pic for what I used. And it wasn't the off-idle response.
The ITBs ran quite smoothly - nice idle, no hunting. I find it hard to describe what it was like when I tried to drive the car quickly in the twisties. Suffice it to say, it wasn't what I wanted. So for now, I'm moving to something that's a bit less unknown.

That said, I'll post as I get back to the ITBs. I have a plan to operate them via DBW and another idea that's what I'll call "the best of both worlds". In fact, tomorrow I pick up the first piece of that effort from my machinist.

What could it possibly be? (IMG:style_emoticons/default/idea.gif)
Will it even work? (IMG:style_emoticons/default/confused24.gif)

You'll just have to keep watching. Oh, and wish me luck!

[Andyrew]

Oh I like that throttle pedal setup. Very nice!

[tygaboy]

The ITB fuel rails used a unique fuel pressure regulator which can't (easily) be made to work with the new Holley fuel rails. So.

I opted to go with a Holley integrated filter/regulator that's preset to support the LS requirements. What's nice is that by mounting it at the front, as pictured (using the same mount that was there for the Aeromotive filter!), I can route the return right back to the pump and only run a single fuel line to the engine.

At the back, I'll add a Y connector and connect to each fuel rail. Each rail is then dead-headed so I eliminate the cross over line at the back of engine. In the end, it's a simpler, tidier set up.

Now it's on to updating the ECU and engine harness.