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Old 09-20-2006, 12:34 AM   #1
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Default Brainstorming here...about a L67 Swap

I was sitting on the ******* thinking about the motor. I got a idea. I then IM'ed Pinky and told him my idea. He agrees with me. Here'* my idea

*This doesn't mean I'm going to do it, it may or may not happen*

Perform a L67 only swap in my car, and convert the tranny to a HD and leave the stock gear ratio. Now that means I'll have 240 hp and a 3.06 gear ratio. And I believe 96-99 SSEi has the 2.96 ratio. Now this means I would be naturally quicker than them stock for stock. Only drawback is that it would take forever to go past 100 mph but I would be very quick to 0-60 and in the quarter mile. Now suppose I drop down to a 3.4 pulley and the necessary mods to support it and drop in PEM'* and a hi-flo cat, I'll be even quicker, now here comes 1.9 rockers and INTENSE PCM and a ported TB and geez whiz, I'll be quicker, now combine that with a shift kit and I'll be shifting HARD and quick.

Nice idea eh?
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Old 09-20-2006, 12:46 AM   #2
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If you convert to the HD diff (the typical hd conversion) you will end up with a 3.29 FDR.
You have a 35:35 or 1:1 gear ratio and a 3.05 diff. The HD diff is actually a 3.29. To get back to the 3.06 you would need to open it up and change the gears to that of a HD trans. (they underdrive it to get 2.9x)
Your non hd diff is physically much smaller then the hd if you didn't already know.
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Old 09-20-2006, 12:47 AM   #3
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Quote:
Originally Posted by 95naSTA
If you convert to the HD diff (the typical hd conversion) you will end up with a 3.29 FDR.
You have a 35:35 or 1:1 gear ratio and a 3.05 diff. The HD diff is actually a 3.29. To get back to the 3.06 you would need to open it up and change the gears to that of a HD trans. (they underdrive it to get 2.9x)
Your non hd diff is physically much smaller then the hd if you didn't already know.
That I did not know
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Old 09-20-2006, 12:52 AM   #4
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Do an HD conversion on the tranny. Once you do that, do an L67 topend swap to your L36. You will then have an advantage over L67 cars because you will have their same setup with higher compression. Then start your mods from there. This will be easier than an L67 swap (IMO), and you should be able to make more power as well, and it should easily be cheaper as well.

Thats what I would do anyways.
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Old 09-20-2006, 12:56 AM   #5
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Quote:
Originally Posted by dbtk2
Do an HD conversion on the tranny. Once you do that, do an L67 topend swap to your L36. You will then have an advantage over L67 cars because you will have their same setup with higher compression. Then start your mods from there. This will be easier than an L67 swap (IMO), and you should be able to make more power as well, and it should easily be cheaper as well.

Thats what I would do anyways.
but wouldnt u have to worry about more kr and having to run lower boost with the l36 bottom?
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Old 09-20-2006, 01:24 AM   #6
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Quote:
Originally Posted by ELMACHOGERACHO
but wouldnt u have to worry about more kr and having to run lower boost with the l36 bottom?
Yep if it was stock.
Pems and less timing (timing more typical of an L67) would probably help.
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Old 09-20-2006, 01:43 AM   #7
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ya i like this idea.....i like it for the fact that

the fastest motors have the L36 bottem end
its more practicle than a full L67 swap
and you have the higher compression

the ONLY thing to worry about is the trans and that is workable, and if you do the trans then go with the 3.29'* and have tire smoking fun
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Old 09-20-2006, 02:38 AM   #8
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Nothing bad about L67 hardware on a N/A motor as long as the tranny is considered
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Old 09-20-2006, 04:30 AM   #9
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Default Re: Brainstorming here...about a L67 Swap

Quote:
Originally Posted by fuelforthesoul1999
I was sitting on the toilet thinking about the motor. I got a idea.
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Old 09-20-2006, 02:17 PM   #10
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Quote:
Originally Posted by ELMACHOGERACHO
but wouldnt u have to worry about more kr and having to run lower boost with the l36 bottom?
With the same size pulley obviously you are going to have more KR. Rule of thumb is run 3-4 pulley sizes larger on an L36 bottom than you would on an L67 with the same mods. You will have less boost, but with higher compression it somewhat makes up for it, and power output is close. Since the M90 robs so much power the faster you spin it, the L36 bottom actually becomes an advantage at a certain point and you will make more power with the L36 bottom then you would the L67.

FWIW, I have the basically the same mods as my friend. He has a Stage 1 TB, PEM'*, and a 3" downpipe, and an L67 bottom end. Other than that, our setups are identical. He runs a 3.0" pulley and gets ~1-2 degrees of KR. I run a 3.4 pulley with my L36 bottom and get 0kr. My car has 3.29 gears and 3000 stall (stock GT) and he has 2.93 gears and 2200 stall convertor (stock GTP). Our cars are very similar weight. We haven't dynoed either car, however if we race from around a 50mph roll (so we both get traction), at 130mph he has pulled ~1 carlength on me. Realistically, at our mod level, it seems as though the cars perform pretty much the same.

The L67 topend swap will be cheaper and easier than the L67 swap, thats the main reason why I would do it. Power output will be similar between the two setups.
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