Thread: Help me plan my rebuild/strengthening

HI folks,

I am going to be tearing my car down to install a big cam, Meth and a few other things. The engine is coming out and its the right time to work on the trans.
I think my trans has issues already. For starters it feels like i have a parking brake lightly dragging at low RPM. the car coasts fine and gets the correct MPG. It just feels like the trans isnt really engaging until about 1500 rpm or so.
It also has an issue where sometimes it sort of half shifts, and pulling the shifter down into second fixes it. It also has a pump whine like a PS pump . Eventually ill buy a Gearstar or built trans, but i need something serviceable for now.

I know the trans needs work, but my budget is limited, so i cant do a true full rebuild (bands, seals, solonoids, valve body etc) So id like to know what to focus on. I also need to strengthen the trans as with the Cam and meth, i should be pushing north of 350hp to the wheels.

1st question, do i rebuild the trans I have or get a JY one? (170 bucks from the JY)

2nd question what are the must do parts of a rebuild? I imagine ill need at least the 1-2 solenoid, and a basic rebuild kit (probably more)

3rd question, i know i need an input shaft, what are the other MUST do mods to handle the power? I dont launch my car, and i dont plan to, but i also want the trans to handle a WOT 3-2 or 2-1 downshift.

In that case i may take the approach of buying a JY trans and just rebuilding that, then i could swap it in when I inevitably brake my current one. That would let me get the car back on the road before it gets cold .

I'd say if your pulling your engine anyway just take it all out and do the trans to. Put that 170 buck and put it back into the trans that's already in your car.
Besides they are already close friend's. You don't want to be the one who splits up friend's do you?

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Originally Posted by wowitsfast

I'd say if your pulling your engine anyway just take it all out and do the trans to. Put that 170 buck and put it back into the trans that's already in your car.
Besides they are already close friend's. You don't want to be the one who splits up friend's do you?

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Yesterday I helped my dad install his IC kit on his 2 door GTP, and it pulled (or felt like it did) a lot harder than my regal did on the same setup. I tend to want to blame the trans since it seems iffy anyway. At any rate, i think i have to at least:
Master rebuild kit,
4340m input sharft
Billet TC.

Originally Posted by SgtMarshal

2 door gtp's are a couple hundred pounds lighter than all the other's.

Its about 150 according to the curb weight. Thats the difference of my dad being in the car.

Originally Posted by GTPpower

I've got a new 4340 input shaft if you're interested. $175 shipped.

I might be!

Originally Posted by SgtMarshal

I thought it would be around there. ported heads and exhaust work should really help wake that thing up, I mean on your Dads car.

I think at some point im going to bite the bullet and get the 3 inch cat back. I already have the DP, and the front Plog. id get headers, but i plan to go turbo and thats just wasting money.

Originally Posted by SgtMarshal

before you get the 3" catback, do some testing to see if it actually helps. I did a 2.5" on one of my gtp's and it kinda felt faster, but my butt dyno isn't very scientific. I've been curious about it for a long time.

Do you mean a dyno test? Id like to, but it depends when i get the car back on the road. Its probably going to be down a few months. At this point, ive got to come up with 1k for the trans, and what not.

Originally Posted by SgtMarshal

it doesn't need to be a dyno, but something that can be duplicated easily so before and after results can be seen.

Id like to, ive seen so few imperical tests on these cars. Its hard to guess what power it makes. Im gonna say 280 to the wheel as is. I pulled pretty hard on my friends v6 accord and that's a 14 second car. It feels like my 280 whp volvo.
Im guessing the cam/headwork/6500rpm shift, will be worth 60 wHP (god i hope so) Dropping to a 2.5 pulley from my 2.9 should be worth 30 (maybe) and Meth + smacking it with a couple of degrees of timing might be worth another 20. Which maybe 100whp ,

But really, i could end up seeing 80, or 60, who knows because there isnt any hard data on these mods.

Have you read my trans build thread?

Originally Posted by BrandonHall10

Have you read my trans build thread?

Ive skimmed it, it looks like its going to run well out of my price range to do all of that. I think i manage 1k for the trans stuff. im trying to maximize that.

If you pull out the fancy stuff like the the 300m IS, 7/8" chain and sprockets, and billet piston it is much more reasonable. The clutch clearances and separator plate mods are low buck (if not free) and really change how the trans feels.

If cost is a major concern, now probably isn't the best time to build a "spare" trans anyway. All my part prices are up at least 25% and availability is spotty on some parts. Borg Warner specifically.

I think the plan is to go for the GXP chain, the 4340 shaft. Ive decided to build the one i have. its started showing its colors the last week, as i was taking friends for rides so i can get before/after impressions. also to your point about parts availability, i dont want to keep waiting because apparently some of these parts arent even being made any more.