QuestionHello Jordan,
I have an 82 Mustang Gt with a 302HO in it. It is all stock except for a few minor mods. I removed most all of the emissions hoses and egr etc. It has just turned 100K and at 89K I refreshed the motor with a Summit engine kit(hypereutectic pistons etc) and installed an Edelbrock Rpm Performer intake with the Edelbrock Rpm Performer carb to match, only I went a slight bit big with the carb and got a 750. If I had known before, I would've gotten a smaller one, but at the time, they only offered a 600cfm then jumped to 750 and I figured 600 was too small. What I had hoped to get was a 650 or something of that range. So, I've been told that it was a little bit of overkill on a carb that big. It runs very dependable and is a daily driver in the summer. However, it runs rich and leaves a big black spot on the ground everywhere I start it and run. The single exhaust(glasspack) is aimed downward so it leaves a big "rich" spot. Without getting a new carb, are there things I can do to equal this problem out? Like cam-ing it or downsizing the carb jets or port and polishing the heads? Also, what can I do to tighten up the suspension because it rides like a boat on water, not like my brother's 88 GT? What mods have you done since you know these engines well? Maybe I can get some tips on things I can do to improve mine. Thanks.
AnswerSorry, but your 750 is just too big. First make sure your timing is dead on at 14 degrees, if timing is off any adjustments on your carb are a compleat waste of time. Tune your carb with a vacume gauge. Most people just turn the mixture screws and use their ears to hear where the proper setting is. A vacume gauge will be much more precise and is a must if you care at all for maximum performance. I dont work with edelbrock carbs but they all have the same basic principals. Get a good tuneing manual so you know how to adjust your accelerator pump, how to change your jets, float level, secondary openings, ect ect. I once ran a 750 vacume secondary on a 351 windsor with stock heads and after extensive tuneing i could only get it to run decent at full throtle and idle. If the throtle was anywhere near half open, the engine would always stumble. I now run a 750 mechanical on a 351 stroked to 377ci with trick flow heads and the carb is just right for it. Any larger would be overkill and the car runs 11 second quarter mile times all day.
For your engine, installing a cam and headers will give you the best results. You already have a great intake and a larger than nessasary carb, your valve train is screaming at you to let more air in. Get a camshaft with around .496 to .520 valve lift and 214-234 degrees duration. The edelbrock RPM cam is a good one. Keep in mind that it will be harder to start and choose your cam based on how often you drive it. Nothing worse than installing a cam, starting the engine, only to have the valves get mashed into the pistons. If you can afford it, get new lifters, springs, pushrods, and rockers. These are more important if you use a more agressive cam, like the performer RPM, so keep that in mind too when you pick a camshaft. Read some mustang magazines that do camshaft reviews and see which one you think is best. Dont bother polishing the heads unless you have nothing better to do. Instead just work an extra job, and save your money and buy some GT-40 P heads for around 600 bucks, or aluminum trick flows for around a thousand. Porting stock heads will increase flow, but unless you start out with a good pair of pre 1970's cylinder heads, the valves are just too small to be bothered with. Heads from the 70's and 80's were designed for emission requirements and fuel econemy. But dont get me wrong, porting will help.
As for the suspension, you probably need to rebuild the entire front end. Keep in mind how old your car is. My 81 cobra had to have every suspension brushing on the car replaced to get it to drive straight. I used the energy suspension rebuild kit that included everything, cost was 300$. A set of lowering springs will work realy good to improve handleing, and when its lower you dont have as much wheel travel, so you can remove your front sway bar. It may wobble a little more, but the lowering springs bring the front down enough so that it doesnt realy matter. The front sway bar is heavy and taking it off is great for speed.
Last, go to this site and order this catalogue http://www.pawengineparts.com/ . Although its over 10 bucks, its well worth it and you will never feel like it was a waste of money. It is huge and has every performance part you can think of. Its great for buying a camshaft because it has every brand of cam, and has each model of cam in a big chart that shows everything from lift, duration, overlap, ect. ect... It makes choosing one much eaiser as you have all the information in one book.
I dont usually type this much out to answer questions but i realy love 82 GT's and all other 79-82's. They have that same front end that looks so awsome, the best looking font end on any mustang in my opinion. Don't change any of the parts to make it look like a 90 GT or LX, i hate it when people do that. Pre 83 mustangs are realy rare. Love the square tail lights, and the hood scoop kicks ass. If you must change your cars appearance and want to buy fancy new bumpers, clear tail lights, and goofy rear wings, tell me and i will buy any parts you replace. If you need any little restoration parts ask me as i have a gradge full of junk ive collected thats for 79-82 mustangs.
