2nd gen F-body w/6L80e????

[STV-R33D]

Is the 6l90 physically larger than the 6l80?

[bsharpe]

it is a little longer but they are basically the same size

[STV-R33D]

Not sure why it fits in my car without cutting the tunnel and not yours but the tranny isn't touching the car anywhere?

[Zapper]

I saw a '70 at SEMA and they had raised the tunnel as well and to me it looked like the motor was sitting way to high and the tunnel made the center console look awkward.

I ended up trimming the pan and running a remote filter. Im also running an external cooler which helped replace the capacity lost from the haircut we gave the pan.

Now the pan sits about a 1/4" higher than the header flange

[dhutton]

I saw a '70 at SEMA and they had raised the tunnel as well and to me it looked like the motor was sitting way to high and the tunnel made the center console look awkward.

I ended up trimming the pan and running a remote filter. Im also running an external cooler which helped replace the capacity lost from the haircut we gave the pan.

Now the pan sits about a 1/4" higher than the header

Did you try a Pontiac G8 GT filter with that modified pan? I think it might work.

Thanks for posting, I will keep this in mind as I am installing a 6l90E in my 69 Camaro.

Don

[Zapper]

The G8 filter won't work as the pan is very shallow and you only have room for a short pick-up and screen.

I needed the extra clearance as I'm running a ridetech air ride system and wanted to dump it as low as possible

Depending on your ride height you might not have to chop it to get the clearance you want. But on the 2nd Gens it definitely drops way below the crossmember

[Trevor @ Texas Speed]

No doubt that the 6L90 is a big trans! My '61 Parkwood wagon is currently at Roadster Shop getting a Fast Track chassis installed, and we sent them one of our TSP turn-key LSA engines with some extra work to bump the power up to 750 HP, along with a 6L90. My wagon already had to have major floor modifications done to accommodate the new chassis, so it was an opportune time to have a new trans tunnel built to fit the 6L90. I went with 3.55:1 gears in the rear for my setup since I'll be running 28" tall tires. A set of 3.23's would've probably been a better bet, but she will be rolling around on a set of 345 drag radials out back. So, it should make it all incredibly fun!

[STV-R33D]

Would 3.73's work with 275's on 17" wheels all the way around with my 6l80e? Again, the 6l80e with the G8 pan seems fit my '71 Formula just fine?

[cpd004]

Would 3.73's work with 275's on 17" wheels all the way around with my 6l80e? Again, the 6l80e with the G8 pan seems fit my '71 Formula just fine?

I'm not sure if this info helps, but a very popular mod for G8 guys is using a gen 5 Camaro gearset. I think it is a 3.45.

If you have any updated pics of your swap, I'd like to see them.

[Motown 454]

I just read through this, very interesting thread. I'd love to see some pictures too.

[STV-R33D]

Sorry guys I wasn't even subscribed to my own thread. I only work on the car a day or two a week, and even less now that it's summer so I haven't gotten to far but I did buy a lot of cool parts!

[cpd004]

Looks great!!

[STV-R33D]

Thanks! I had pull the tranny to deal with the fixed yoke issue. I decided to do a slip yoke conversion pulling the car apart was the easiest way to get the tranny out. I swear I've done just about everything twice building this car!

[STV-R33D]

I sent both ECM's to Speartech so he can program them for the 3:73 gears I went with and match the ECM's so the manual shift will work with the shifter I bought from him. The shifter is sort of tall, not sure if it looks good or not? I'll have that plastic piece removed and a new boot made to fit the console. What do you think, is it too tall? I'm just going to have to like it...it was expensive.

[srh3trinity]

Just leave the shifter as is until you get the seats in and drive it. Will the knob come off? If so, it may be as simple as pulling the knob down, taking an inch or two out and re-mounting the knob.

[dhutton]

I have the same shifter and I'm installing it in my 69. Same concerns about the height but I looked around and could not find any workable alternatives if you want the shift buttons.

Don

[Cape TA]

About to do this same swap in my 71 firebird, hoping I don't have to cut my trans tunnel as well. Thanks for all the good info in here!

[STV-R33D]

My car is 99% done and I wish I would have cut the tunnel and raised the motor and tranny. I only had about 2.5" of clearance on the tranny pan when I set up the car the way I wanted it to look...nice and low. I ended up cranking up all the coil overs to get clearance but now the car is almost at stock height and it has lost some of its cool factor to me especially with the low profile tires. I had a speed shop go over the car and they changed a few things I did and tuned it.

383HP at the rear wheels...not bad for a LS2!

[Cape TA]

My car is 99% done and I wish I would have cut the tunnel and raised the motor and tranny. I only had about 2.5" of clearance on the tranny pan when I set up the car the way I wanted it to look...nice and low. I ended up cranking up all the coil overs to get clearance but now the car is almost at stock height and it has lost some of its cool factor to me especially with the low profile tires. I had a speed shop go over the car and they changed a few things I did and tuned it.

383HP at the rear wheels...not bad for a LS2!

And that's with having the g8 pan? Damn I really wasn't wanting to cut my floor and mess with my interior again, I just got it all nice and pretty lol

[STV-R33D]

Yeah, I have the G8 pan. I'm being generous with the 2.5" it's been awhile since I took that measurement it may have been barely 2"?

Did you buy your LS yet?