Here are all the things i know so you guys could possibly shed some light on the issue.

I have a haltech e6x and engine has to spin fast enough for the ecu to pick up signal and start.

It only happens on the first start of a day. It just turns kinda slow and definitely not fast enough
Battery is good. I even tried using 2 new batteries jumped to each other and it still wasnt enough. I also have a big battery charger that can give 12v 50 amp or 12v 250 amp. Both setting are not enough.
Battery is relocated to passenger bin and the connections to the breaker(only one i checked) gets really hot after trying to start for long time. Too hot to touch. I got burnt...
CHecked with laptop before trying to start and battery has 12v every time.

After trying forever it will eventually start and after it has started once- she starts like a champ everytime after that. I mean she spins like a beast and starts ideally.

WHy the hell does she spin so slow on the first attempt to start.

My guess and assumption is tghat the 2cycle oil im using might make the housings kinda sticky and makes the engine spin all slow. But after she starts and gets fresh gas and 2 cycle oil shes lubed enough to spin freely? I use klotz benol 2clycle castor racing oil.
Some one please shes some light on this.

 

I'm in the same boat. I think I have a parasitic draw on the battery which drags the battery capacity down enough overnight to make it slowly spin on startup. I pre-mix as well, and also use 20W-50 oil, so that might have something to do with it as well. Compression is fine, but it has a hiccup, kind of a gallop on initial start up when cold (usually a sign of lower compression engines).

I think the first step is to figure out what the parasitic draw is. I'm highly suspecting the starter now that I'm thinking of it. I used Raksj04's starter for a little bit and it worked just fine; strong start up each time. Once I got his car back together after the engine build, I went out and bought a remanufactured starter from O'Reilly Auto Parts and I think that's when it started.

 

op.. earth cable is insufficient .. very often with battery relocation you need to run an 0 or 1 gauge wire from battery to gearbox as earth return

just strapping from battery to body and gearbox to body is often not good enough

 

Not necessarily true, Bumpstart, but the reasoning is well-founded. A poor ground connection means power is being burnt off as heat instead of making it to the starter. Aaron Cake goes into greater detail in the Grounds FAQ here: Proper RX-7 Grounding Procedures

My battery is also in the passenger side storage bin and is grounded to the sheetmetal using one of the hinge bolt holes. I cleaned up the threads with a dremel & wire wheel, then ran a bolt up from the underside to act as a stud and finished it off nice and neat with an acorn nut.

Just remember, only BARE SHINY METAL works as a ground point. Put some dielectric grease on it to protect it from rust and it should fix the problem.

As for the first start being slow, that makes sense. A cold engine takes the most effort to turn over. Oil Viscosity factors in as well. On my old 13B setup, 10w-40 in our infamous Ohio winters made my car reluctant to start. One trick I've found useful is the so-called "Force Prime" technique. You basically turn the key on, wait 5-10 seconds, then turn the key off. Repeat a few times. This pressurises the fuel lines so the pump doesn't have to work as hard, which saves a little juice that is pulled over to the starter. My 20B can be pretty grumpy, especially with its air/fuel mixture being excessively rich, but Force Priming will get it fired up no matter what.

 

and thats just how i used to have mine too.. cept i went through three slow cranking starters, and hot cables on the battery , till i got smart and added the full earth return cable and revised the gearbox as the earth bus bar... now i have much faster cranking .. and 3 good starters

 

Thanks. I'll try adding grounds. If that doesn't work I'll wire relay to starter for direct 12v from battery.

 

SO..... I go jack the car up because im looking to take out a starter bolt to add a ground... and i quickly realize that i dont have a ground on there. I must have "lost it" during engine bay clean up and harness "tuck/simplify".

I added a fat 4ga ground runing directly from battery to starter and it seems to be working now.

Question: WHere does the factory starter bolt ground come from?

 

From the battery to the fender to the starter bolt.