What should I do?

[Omnivium]

I have a 87 T Type with the 307 pretty much bone stock. Car runs strong. I would like to upgrade it a little, get a little more power out of it. I know it won't ever be really fast but would like a little something for the time being. Not swapping it for a 350 so please don't suggest it hahaha. It's got the 7A heads first thing I wanna do is go to the junk yard and find some 5A heads and put those in. I would like to possibly get true duals (obviously would need to get a modified transmission cross-member for that) and maybe new headers to go with that. I might just do what someone told me to do on here and just get a dual outlet muffler and do it that way, unsure yet. Maybe cold air induction also, saw somewhere about that dual snorkel thing for a cold air induction, or do they make cold air intakes for the 307s? I don't know what else I should do to it to get more power. Sorry I'm a noob with car stuff now ahaha, learning though! But what do you guys think? What would you do? Like I said car is basically bone stock and have time and some money to invest in the car. Open to anything besides swapping the engine lol. Thanks.

 

[Evan11]

About all you could do is add headers & true duals. Fake duals aren't gonna help much if any. Better rear end gears would make it run a lil better off the line.

 

[Omnivium]

Also swapping out the 7A heads for the 5A heads does anything at all need to be changed?

 

[Omnivium]

About all you could do is add headers & true duals. Fake duals aren't gonna help much if any. Better rear end gears would make it run a lil better off the line.

Probably just gonna end up doing that then paint it when I can.

 

[MrHernandez]

Intake, headers, cam, rearend, duals, carb.....ebay, craigslist, and amazon are your friends

 

[UgotBronx]

I wanted to keep the OG 307 in mine and I did all of what has been suggested here. Dual exhaust & headers, 373 gears, QJET rebuilt once then i put on the edelbrock 600. The most noticeable upgrade was the rear and the exhaust. rear still going strong but the headers and exhausted lasted just about 5 years so if that works for you then invest the $$. GOOD LUCK!

 

[jlat]

hello; What's the transmition in that car?
IBBY

 

[88cscb]

I wanted to keep the OG 307 in mine and I did all of what has been suggested here. Dual exhaust & headers, 373 gears, QJET rebuilt once then i put on the edelbrock 600. The most noticeable upgrade was the rear and the exhaust. rear still going strong but the headers and exhausted lasted just about 5 years so if that works for you then invest the $$. GOOD LUCK!

When you went 373's in the rear, how does she run on the highway at 70-75mph. I have 256's in the rear and its dog slow off the line., looking to go. Either 3.42' 3.55 or 3,73. But concerned about it spooling 3000 rpm on the freeway. I have a 4 speed 200r4

 

[dogsht]

Your single biggest acceleration improvement & bang for buck will come from a rear end/gear swap. Other than that I would just get an old school performance oriented shop/mechanic to put in an advance curve kit and give it what timing you can, to get it peppy. You will pick up some noticeable power here but mostly you gain responsiveness. It will/can feel eager not sluggish and pull stronger longer without falling on its face. (Unless your Q-jet is in need of a rebuild) Last I would add a cheap Summit or Jegs brand cat back exhaust system mostly for a nice low v8 rumble. Beyond that keep your money for something else.

You both should have a 200-4R if its factory original. You both have 15" wheels. A stock 307 won't accelerate any quicker in the 1/4 mile if you run it past about 4,100 rpms in 3rd gear. So a 3.73 is about the best gear even for its relatively poor power mostly because it doesn't make any more power beyond that with the stock heads & cam.

With stock 26" tall tires a 3.73 will turn 68 mph in overdrive at 2,200 rpms.
With 28" (275/60/15) a 3.73 will turn 73 mph in overdrive at 2,200 rpms.

I had an 88 307 with 2.56s. When I changed to a 3.73 it got a lot quicker and would burn tires at a stoplight easily. Mileage in town got better but fell on the interstate. Overall mileage stayed about the same for me.

http://www.wallaceracing.com/calcmph.php

Any 3.42, 3.55 or 3.73 would be a good choice with little difference between them but a noticeable jump coming from 2.56s or taller. (lower numerically)

 

[88cscb]

Great info/ feedback. I think I will order the summit 3.73 gears for it soon. With the 256 I can't even sqeak the tires.