GTM #534 Build Log

[Shoeless]

MoTeC is essentially a top tier motorsports product that outperforms all other "hobby" ECUs in every aspect.

Is it easier to tune, absolutely not. I have taken some classes online for tuning and specific to MoTeC and still had issues. I got some help to get mine running and idling in a reasonable manner to at least move the car around and will be having an experienced tuner finish it off for me.

When I say full MoTeC, for me that is an M170 ECU and C127 Dash.

If you are interested in building your own harness, than you and I should talk. Depending what level of wiring you want to do, TXL wire, Tefzel wire,...? Than you will spend a boatload in tooling. I spent over $3,000 just in tooling to build mine and am about to open a tool rental business.

[beeman]

Tuning is actually not an enigma. I just got done street tuning a Honda RBB (K24 VTEC/VTC). Self-taught with Youtube videos and HP Academy course. I'd much rather tune an LS. With VTEC/VTC, you have to tune separate fuel and ignition tables for low and high cam (VTEC), as well as 5 different cam degree tables (0-50 degrees cam rotation, tune every 10 degrees!) for both low and high cam. Just did a 1600 mile trip in that car running it 10/10. Yes, I couldn't find absolute peak HP/TQ without a dyno. Might find 5 more HP on a dyno (NA 200hp engine).

Most ECUs will give you a basemap for the engine you are using to get you started.

[Shoeless]

Love my HP Academy videos and looked around long and hard for someone to rent me dyno time on an load bearing dyno. Closest I found was a non load bearing dyno, but that's just not the tool you need to do it properly.

My AEM Infinity Series 7 (still for sale with my CD-7) offered an LS3 base map and I was able to get my engine to fire up in about 3 minutes. Cleaned some things up and was able to drive it. I had my knock detection setup and tried some left foot breaking and logging, but trying to hold a 625 HP engine in the cell long enough to get a good reading was difficult . But I did get it to the point it was drivable and to the tuner.

I don't think MoTeC had any base map available. I essentially copied my AEM tune into my MoTeC, but the logic in the MoTeC is different so I struggled a bit. Even with the HP Academy video on MoTeC idle tuning didn't help me much. Oh its worth saying I went with JRR software package in the MoTeC, so that's pretty different from the GPR package. JRR added a few functions that I thought worked better for me. One cool function in the MoTeC was Quick Q. Once you set your base VE table you can run on any cell and it measures the lambda against the target, hit the Q key, and it automatically tunes that cell for you. I did pretty good with this feature, but nowhere near max HP and Torque.

[beeman]

Love my HP Academy videos and looked around long and hard for someone to rent me dyno time on an load bearing dyno.

Great points. I would not enjoy tuning a 650 hp engine on the street. 3rd gear pulls on a country highway were easily doable with 200 HP
The Honda engine is getting a turbo this summer, will be about 400hp, still plan to street tune.
Sorry for the thread hijack.

[ohmygosuness]

MoTeC is essentially a top tier motorsports product that outperforms all other "hobby" ECUs in every aspect.

Is it easier to tune, absolutely not. I have taken some classes online for tuning and specific to MoTeC and still had issues. I got some help to get mine running and idling in a reasonable manner to at least move the car around and will be having an experienced tuner finish it off for me.

When I say full MoTeC, for me that is an M170 ECU and C127 Dash.

If you are interested in building your own harness, than you and I should talk. Depending what level of wiring you want to do, TXL wire, Tefzel wire,...? Than you will spend a boatload in tooling. I spent over $3,000 just in tooling to build mine and am about to open a tool rental business.

Currently, I am leaning towards MoTec. What about Haltech or Holley? I hear good things about them and they're half the price.

Is there really no company out there that does custome length harness for a reasonable price?

I'd build a harness if I have to. It would definitely be a nice skill to learn. But I also like to keep my options open.

[ohmygosuness]

Sorry for the thread hijack.

Not at all. I appreciate all/any input.

[ohmygosuness]

Not to change the subject but does anyone have decent pics of how the fuel tanks should be mounted? The manual just show one pic of already installed tanks. It really doesn't look like anything is holding them in place other than maybe the seats and crossover tube.

[Shoeless]

Currently, I am leaning towards MoTec. What about Haltech or Holley? I hear good things about them and they're half the price.

Is there really no company out there that does custome length harness for a reasonable price?

I'd build a harness if I have to. It would definitely be a nice skill to learn. But I also like to keep my options open.

Haltech and Holley are considered hobby level ECUs and as such will be half the price. Can they work, sure there are successful builds out there, but in this instance you get what you pay for. This was a hard lesson for me to learn. I knew nothing about motorsports ECUs and wiring when I started my journey years ago. All I knew was that I wanted to learn how to build my own harness and do my own tuning (at least get it running and driving). So I chose AEM to begin with, in the end that was a mistake. AEM stopped supporting my ECU and they sold out to Holley. Once that happened I ripped it all out of my GTM. You won't see MoTeC playing any of those stupid games. They truly are a top tier company that stands behind their products and its a benchmark for high end performance.

Depending what MoTeC ECU you go with you will either have a Deutsch Auto Sports connector, like my M170 or the other Molex (I believe its a Molex) product for a plug like an M130. The takeaway here is you can run a GTM on a M130 or M170 but you may want to also add a C127 dash as it will allow you to expand the number of inputs and outputs. I have the tooling that will handle both of these plugs flawlessly (even with RaceSpecs new gold solid contact for the Molex connector).

I'm not aware of anyone that does custom length harnesses, especially at a reasonable price. I could make you a pig tail type harness that has the plugs and say 15 ft of wires attached, but we'd have to design your power management section as well. Planning on these harnesses is sometimes just as much work as building them.

[Shoeless]

Not to change the subject but does anyone have decent pics of how the fuel tanks should be mounted? The manual just show one pic of already installed tanks. It really doesn't look like anything is holding them in place other than maybe the seats and crossover tube.

The tanks are literally just stuffed in the opening and then the tank covers hold them in place. If you are going with Aluminum tanks you may need to add additional foam and supports, but if donor tanks, just set them in there and the tank covers hold them in place.

[crash]

Why did I say I would likely go MoTec with future builds? Because it is a race industry standard. I have no doubts that the full race ECU that I am currently running in the race car does everything and maybe even more than a MoTec standard unit, but the fact that there are only a couple of tuners here in the US that can work with the ECU is a much bigger draw back than I had anticipated. You will find multiple tuners in almost all major US cities that can work on a MoTec unit.

Harnesses. Ugh. My last one cost over $5k and the builder did not do it the way I had asked him so as soon as I got it installed and saw how the knock sensors wiring was run I got out my nippers and cut the harness apart! Really not happy about that, but needed the harness to make it to a race and so I had to "modify" it straight away. Sometimes it is very hard to get a builder to understand something when it is not assembled and in front of them. The way the knock sensor wiring was run originally caused it to run right next to the exhaust header, whereas the way I wanted it (not standard for an LS setup) ran everything down the bottom of the engine.

I have not done this, but given the fact that I have seen some "motorsports" harnesses available online for relatively low prices...like a few hundred $$...and they appear to have real mil spec connectors, I think I might give one of those a try and see if it fits okay and just needs minor modifications. Worst case scenario is that you overpay slightly for your connectors and have to repin them. Awesome wiring source, and the one I primarily use is prowireusa.com.

I can send you to the guy that made my custom harness, just expect $5k range for cost...and maybe not 100% the way you want it. LOL!

I did suggest to the guy I used that I thought he was missing out on a lot of customers that would happily buy a "standardized" LS motorsports harness that would be in the range of $2,500.00. His reply to me was "why would I do that when I am backed up for months at $5k-$10k for my harnesses?" Guess he's got a point.

[Windsor]

I did suggest to the guy I used that I thought he was missing out on a lot of customers that would happily buy a "standardized" LS motorsports harness that would be in the range of $2,500.00. His reply to me was "why would I do that when I am backed up for months at $5k-$10k for my harnesses?" Guess he's got a point.

Because he can bring in a kid for cheap to lay out the standard harness and make more $/hr selling a handful of those every month. Of course it would eat some of his time getting the hired hand set up and in the right direction, but should cover those losses pretty quick.

[frankenford]

"I spent over $3,000 just in tooling to build mine and am about to open a tool rental business."

I'll rent your corner scales for a couple weeks lol

[frankenford]

I went with a Holley terminator x Max ecu. It came with a pretty nice harness but like everyone has said it had to be modified. With the intake flipped and depending on how you route it you must pay close attention to cylinder numbers for the injectors and coils. I had to repin all those as well as lengthen the oil pressure sensor. Holley has lots of limitations with the terminator, only 1 wideband 4 inputs and 4 outputs just for starters and I find their program to be restrictive too. Even though I haven't reached the point of starting my engine yet I have regrets with going with Holley. Doing it over again I would have went with a megasquirt3. I know that will make some people cringe but I haven't seen anything the big names do that the ms3 can't. Not saying its equal to or better than motec but it's what I'm already familiar with and I know how to use tunerstudio. Haltec did look pretty appealing for my price range as well.

[Shoeless]

"I spent over $3,000 just in tooling to build mine and am about to open a tool rental business."

I'll rent your corner scales for a couple weeks lol

If you are in S FL, we can make this happen shipping would be a killer at the weight of these things.

[ohmygosuness]

Is there such thing as an aftermarket/universal clock spring for the horn? One that works with the steering wheel from FFR. I accidentally broke my clock spring it came off a C6 steering column.

[Shoeless]

Not sure about a universal. I was lucky enough to have beeman donate the one he pulled from another GM car and already prepped and dropped it right in mine with some clearance work on my Momo adapter.

I can't remember the model car he got it off of or find the link he was nice enough to send me of all his prep work, but I know that he documented the whole process. Hopefully he can chime in here with the details. If i remember it was very cost effective as well.

[beeman]

Not sure about a universal. I was lucky enough to have beeman donate the one he pulled from another GM car and already prepped and dropped it right in mine with some clearance work on my Momo adapter.

I can't remember the model car he got it off of or find the link he was nice enough to send me of all his prep work, but I know that he documented the whole process. Hopefully he can chime in here with the details. If i remember it was very cost effective as well.

I couldn't find it but Google did! Was on the other forum...

https://www.ffcars.com/threads/offic...thread.554785/

[ohmygosuness]

I couldn't find it but Google did! Was on the other forum...

https://www.ffcars.com/threads/offic...thread.554785/

That's very impressive! I'll definitely look into this spring lock if you can get it for only $12 lol. The C6 OEM one goes for around $100 used.

Was this 3D printed?
Where did you get the buttons?

[beeman]

That's very impressive! I'll definitely look into this spring lock if you can get it for only $12 lol. The C6 OEM one goes for around $100 used.

Was this 3D printed?
Where did you get the buttons?

Are you using the FFR steering wheel? I went with another steering wheel, the plate fits the FFR wheel better, was keeping it for another project, PM me if you might want to use it.

[ohmygosuness]

Are you using the FFR steering wheel? I went with another steering wheel, the plate fits the FFR wheel better, was keeping it for another project, PM me if you might want to use it.

I'll be using the FFR steering wheel (I think it's Momo?). I'm also thinking about keeping the Vette blinker/wiper switches since I took those off the donor and they're already attached to the steering column.

[beeman]

I'll be using the FFR steering wheel (I think it's Momo?). I'm also thinking about keeping the Vette blinker/wiper switches since I took those off the donor and they're already attached to the steering column.

I don't think the FFR supplied wheel is MOMO, Sparco, etc, there weren't any markings on it. It's a very nice wheel though, and very comfortable, I only changed it because I wanted a different color.

[VRaptor SpeedWorks, LLC]

I think the steering wheel adapter has the MOMO bolt pattern......maybe that's what we're getting at?

[beeman]

I think the steering wheel adapter has the MOMO bolt pattern......maybe that's what we're getting at?

Yes, Momo bolt pattern

[ohmygosuness]

I think the steering wheel adapter has the MOMO bolt pattern......maybe that's what we're getting at?

Oh you're right. The adaptor is Momo. But the wheel itself doesn't have a brand, just like the supplied seats. Looks good quality though.

[ohmygosuness]

I moved to a different state and I decided to set the body "loosely" on the chassis when it gets transported.
Then I noticed this big gap in the rear wheel well.
Either the body warped for sitting on the floor for 3 years or this one just have really bad fitment.
gap.jpg

[Shoeless]

Did the body get pulled away from the frame and is now not all the way down where it wraps under the chassis (and then hugs it properly)?

[VRaptor SpeedWorks, LLC]

I'm with Shoeless.....there is a little stub of chassis tube sticking out in front of the rear wheel arch.....looks like maybe the body is hung up and sitting on top of that stub instead of wrapping around the bottom of the chassis?...or the door striker mount on the chassis is holding the body out?

[ohmygosuness]

It was able to hug the bottom of the chassis when I took delivery fee years ago. It is unable to do that anymore. The sides are flaring out a little. If the body warps over time, I'm thinking about lean it against a wall on its left side for a year, then right side for a year to "bend" it back to shape lol.

[VRaptor SpeedWorks, LLC]

If you can't get the bottom of the body to wrap down around the bottom of the chassis, something is holding it up. Either it's hung up on the door hinges so it won't go forward far enough to clear the door strikers or something else is holding it out. Once you get it positioned properly, even if it's warped out a bit, you should be able to easily push it back into place, drill and cleco that bottom flange to the bottom of the chassis to hold it in place.

[crash]

If you can't get the bottom of the body to wrap down around the bottom of the chassis, something is holding it up. Either it's hung up on the door hinges so it won't go forward far enough to clear the door strikers or something else is holding it out. Once you get it positioned properly, even if it's warped out a bit, you should be able to easily push it back into place, drill and cleco that bottom flange to the bottom of the chassis to hold it in place.

I agree. Fiberglass is very "bendy" and you should be able to move things where you want them, or where they should be, and they will stay there as long as you have a solid mount to attach to.

[Shoeless]

Shane and crash are spot on here. If the body is truly warped a bit, you should be able to easily push against it to bend to back in place, IF no frame pieces are in the way.

The pic may be a little deceiving, but it just looks like the body is not down far enough (gap between top of tire and body) to wrap under the frame tubes like it should.

[VRaptor SpeedWorks, LLC]

Another area to check is the main front aluminum vertical pieces that are captured by the front suspension. Those are typically a bit long at the rear edge...which can cause a chain reaction.....if the leading cowl edge of the body is hitting that aluminum and holding the body back, then the sides won't tuck down behind the door hinges at the A-pillar....and the body won't move forward enough to get past the door striker mount....and I would say it's likely that the door striker mounts are what's keeping the sides pushed out like in the photo.

The very front edge of the body that wraps down around the bottom of the chassis can also hang up on that chassis stub....and if that won't drop down....again, it causes the body to not tuck in behind the door hinges and causes the same thing.

[ohmygosuness]

Thank you all for the advice. I'll keep these tips in mind. This is just something I noticed when transporting the car. Since I'm no where near completing the go-kart stage yet, I'll just tackle the body fitment when I'm pretty much done with everything else (probably years later lol).