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1G Trannys


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#1
octagondd

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I have an 86 HF and wanted to find out if the 1G SI tranny, is the exact same bolt pattern, size etc. Is it just the gear ratios that are different?

 

I am interested in getting a little more Pep out of my pepper, but it has to be the exact same bolt pattern and size since I have converted my car to all electric and have an adapter plate between the tranny and the electric motor. Maybe the answer is to just change the gear ratios on the input shaft? I am not an experienced car person, so please pardon my ignorance.

 

Thanks,

Dave



#2
jsgprod

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Yes, they have the same bolt pattern. It's a direct swap.

If you love the Elise, drive a Se7en - Caterham or whatever...
It has even less content than the Elise, is less graceful looking
...and changes direction like a ping pong ball whacked by Thor.

scull+gif+1.gif

jsgprods Gallery


#3
octagondd

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Yes, they have the same bolt pattern. It's a direct swap.

Great, Thank you.



#4
gtpilot

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...since I have converted my car to all electric and have an adapter plate between the tranny and the electric motor...

 

Pictures please and a description of how you did the conversion?



#5
PuddleSkipper

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Pictures please and a description of how you did the conversion?

 

I second that, PLEASE! Looking at doing the same thing down the road, like the idea that all the walgreens in my area have free chargers so I could basically drive up and down the road for free (well no gas anyway). Also thinking about getting another carby because they would take very little to be EMP proof.



#6
octagondd

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This was quite a journey for me. It took five years due to life changes like getting married, foreclosure, moving, baby, etc. It was also tough because I didn't know much about cars, or tools and didn't have a garage for some of the time. Luckily I had a couple friends who helped me out, but this car is like a jr. high science project due to my try, try again and re-try again efforts to make it work.

 

Here is the project blog:

erxperience

 

and here are a few photos hopefully, if they link.

 

IMG_5023.JPG

 

IMG_5081.JPG

 

P3313304.JPG

 

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20121203-00002.jpg

 

PC087908.JPG



#7
PuddleSkipper

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Is there a good site where you learned all your info? I'm still learning about wiring.............Great build btw!!



#8
octagondd

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Is there a good site where you learned all your info? I'm still learning about wiring.............Great build btw!!

Mainly DIYelectriccar.com, and evtv.me although Jack on evtv can rub people the wrong way and his videos are brutal to get through since they are 2-3 hours long sometimes. The earliest 20-30 videos on evtv are the most helpful until you are up to speed on all the tech. I think they did an almost bolt by bolt conversion of a mini cooper. Also check youtube for others. I was personally inspired by a guy from New Zealand I think, named Gavin. https://www.youtube....t7think7clearly

 

evalbum has a lot of conversions and if you have a certain car in mind, then you can check there to see if anyone has done it already and contact them or check their blog.

 

My conversion has cost around 17K so far, so it is an expensive project, but depending on the distance and speed you need to go it can be much lower. Also, I bought all new parts, and others have gone cheaper by finding used parts or cheap ebay sales, old forklift motors, etc.



#9
jsgprod

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Nice Job! Those are some nice batteries too! I've looked at them in the past when I was entertaining an electric conversion.

 

I haven't read through your build blog yet but plan to when I have some time. Since I haven't yet, would you mind sharing what voltage your primarily running the car at?

 

Also, going back to your original question regarding gear ratios and wanting to get a lower final drive. An Si gearbox will definitely give you a lower gear ratio than anything that came in the HFs but the HFs actually came with three different final drive ratios. Depending on where the car was originally sold in the US, 49st, Cali, and mountain regions. Obviously the most common is the 49 state models which (according to the manuals) came with a 2.95:1 FD. The other two (again, according to the manuals) were 3.55:1 and 4.06:1 respectively.

 

So, depending on which FD you currently have you could be looking at using significantly different gears with the Si box than you are with the HF box. I know you're not using all the gears...are you?

 

Again, it looks like you've done a really nice job considering where you admittedly started at. I'm impressed.

 

Jay


If you love the Elise, drive a Se7en - Caterham or whatever...
It has even less content than the Elise, is less graceful looking
...and changes direction like a ping pong ball whacked by Thor.

scull+gif+1.gif

jsgprods Gallery


#10
gtpilot

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Read your whole blog - a lot of perseverance, congratulations on the completion! 

 

Back to Jay's question(s) - what RPM does your motor spin and do you have a torque curve that you could share?  That would make the most sense for choosing the gearing that you really want.

 

Kirk



#11
RETROCRX

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Cool......I worked in the Electric Car biz for 2 years, did a full electric conversion on a Chevy Equinox for GM......But I worked mainly on the mechanical design and prototype build side of things.

 

Anyway, how are you shifting gears without a clutch??  I haven't read your blog so forgive me if the answer is in there!

 

Rob


Must.....go......racing.......


#12
octagondd

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I didn't do a whole lot of calculations since I didn't know how to. I found an EV calculator and learned how to use it, but it didn't have any curves, just static numbers at speed. Mostly, I went by what others had done in the same car. I was originally shooting for as much efficiency as possible, but now that I am up and running, and have plenty of range, I want to play a little more. Part of my issue is I could get a controller with more power output and that would help, but changing the gear ratios could also help. I realize this will then change my rpms, but that is fine.

 

I am running (44) 3.2 volt cells in series for 140.8 volts. I usually use first through third gears. The motor likes to be between 2500 and 3500 rpms for power, efficiency and cooling. It is recommended not to go over 5500 rpms, which is convenient since this is the red zone on the 86 HF rpm gauge. In 3rd gear going 60 mph I am at 3200 rpm. At 70mph I am at 3700 rpm. I also have 15" tires which make my speedo show about 2mph high at 60 mph or so, but the numbers I gave are the actual speeds and not the speedo.

 

I believe I have an High Altitude transmission based on the numbers I saw in another thread here. When I plug those gear ratios into the EV calculator it is matching what I see on my rpm gauge.



#13
octagondd

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Cool......I worked in the Electric Car biz for 2 years, did a full electric conversion on a Chevy Equinox for GM......But I worked mainly on the mechanical design and prototype build side of things.

 

Anyway, how are you shifting gears without a clutch??  I haven't read your blog so forgive me if the answer is in there!

 

Rob

Basically, I just hold the shifter lightly against the next gear and as the rpms come down from the previous gear, it slides in. Down shifting is a bit tougher since it requires giving a little boost to the rpms with the accelerator, then it slips into gear. 

 

This is not optimal from a fast shifting/performance or even safety perspective, but simpler for me since adding the clutch disk/flywheel complicates the motor coupling a bit. This car is mainly for commuting and was never intended for performance, so not your usual project on this forum. After doing the project, I now wish I had kept the clutch.



#14
RETROCRX

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Ah, the same way you would do it with the normal engine then. Thats cool.
Must.....go......racing.......


#15
octagondd

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Ah, the same way you would do it with the normal engine then. Thats cool.

Yes, only difference is no engine braking when letting off the accelerator. Basically like being in neutral. Just loss of energy from rotational losses and friction. Also, you must use parking brake to park. You can't put it in gear on any slope and have it stay. It just rolls.