[Project] Project 1988 T/A GTA

[Lortay5408]

Hello all,

I bought a 1988 Pontiac Firebird Trans Am GTA this summer and enjoyed it thoroughly.
Now that it is in storage, I have time to think about modifications and what my possibilities are for it. No time crunch on this one, just looking to learn and have some accomplishments.
My goals and ideas may(will) change as they progress but hopefully everyone here can keep me on a path to success....and coolness .

Here are some ideas:

-Improve exhaust. I have a poopy and annoying one now. Hopefully next year, I can drop $$$ on Hooker headers and y-pipe and a Hooker Aerochamber. If not Hookers, I am in contact with Dyno Don and the price is just a tad more.

-Pull 305 and replace with 355 TPI. For the 355 I have mildy worked Iron L98 heads, but I plan on doing max work on them. Don't have money for good aftermarket yet. Almost 100% set on the LT4 hot cam kit as it maxes out around .500" lift, which is about the limit of the heads.

-Strengthen 700R4.

-Replace high gear posi with a 3.45 or a 3.23 Posi.

-Replace front discs and rear drums with LS1 brakes.

-Cosmetic stuff like interior headliner, paint, and better lights.

[Lortay5408]

The digital dash was very dim and the only light that worked was the center light in the middle behind the MPH reader.

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I yanked it all out and replaced the bulbs and cleaned the contact surfaces. Helped a TON. Now it looks like a Christmas Tree at night instead of scary.

[Lortay5408]

My brother-in-law has his own machine shop so he let me give it a go this weekend on the 350 I plan on dropping in the GTA.
We learned it was a GM Crate motor, casting #: 10243880.

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Scraping off gasket crud and residue
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Wirebrush the surface stuff off
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All the specs for crank were right on the money.
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Bored it .010 then .020 then .027 over. Will do it full .030 after the bores are honed.
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We were just a few thousandths over GM spec of 8.025" from crank surface to deck surface. Took .003" on each side.
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When I get more time off from work we'll finish out the machining process and make sure the crank is good. Then it's time to order parts!!!

[DynoDave]

Sweet! Another '88 T/A. I look forward to following your build.

[ruckusz28]

Sounds tasteful! Random question. Will the stock tpi setup flow enough for a 355?

[hoogiesngrinderz]

Sounds tasteful! Random question. Will the stock tpi setup flow enough for a 355?

Stock TPI setups are good up to 350hp(ish) with nice heads.

[ruckusz28]

Good to know

[hoogiesngrinderz]

Flow numbers:
http://www.hobracing.com/tech/tpi_flow.asp

[Lortay5408]

[MENTION=3597]ruckusz28[/MENTION]
Yeah, I plan on using the stock setup that's on the 305 now. Going budget on this one unless I can find a good deal on a better aftermarket set-up(not going to happen!)

I'm not going for a high HP burner, just something that sounds nice and is fun to cruise in. I'll save the good stuff after I get a build under my belt. I'm thinking carbed C10!

[ruckusz28]

I'm interested in how this goes. Best of luck

[Lortay5408]

Thanks man! I forgot to say that all of the TPI stuff will be ported, and probably at least a better throttle body. If I was going to spin it up to 6000 rpm, I'd do TBI or carb. Hoping to get about 330 hp out of it!

[hoogiesngrinderz]

Stock throttle body isn't a restriction until 400 or so with an airfoil, I believe the numbers posted around the net are a little low. Even the best ported stock TPI base/runners are only good to about 400. Biggest restriction comes from heads and especially the MAF.

I will probably switch my IROC over to a 7730 ECM, MS3 based PNP setup, or pull the Accel DFI Gen6 out of the Bel Air. 52mm TB wouldn't hurt with my setup.

TBI setups are terrible for high hp engines unless you use an aftermarket. OEM stuff can work but just isn't worth it anymore.

[Lortay5408]

I'd do Vortec heads with the TBI and flow them like mad.

Your IROC is fine, you need to start driving it soon!

[hoogiesngrinderz]

You could do a $3000 set of AFR's and GM TBI, still would only make 400hp at the crank (with ported parts)

Not sure when the IROC comes back. Don't really care at the moment.

[Lortay5408]

Another picture blitz from a day in the shop....

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Torque plates to finish the bore from 4.027" to 4.0305"

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Went with 5.7" rods over 6" rods.

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Cleaning them up.

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Picked up cheap heads. Dude must have just ripped it.

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Getting the heads apart.

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New parts are better than Christmas! Pistons.

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Finished honing. Cylinders are within spec top to bottom and in roundness. Off to the cleaning tank.

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Crank was sent out to be reground on Monday. It will get balanced next time I can make it out to the shop after this semester is over.