Engine mods while re&re LIM [Archive] - GrandAmGT.com Forum


View Full Version : Engine mods while re&re LIM

03-31-2005, 02:19 PM
What kind of engine mods can I do for a 1999 gagt while re&re the lower intake manifold gasket set? I am thinking internal parts.

My first post so please don't bull sh!t me. :ec: :slim

03-31-2005, 02:29 PM
Be careful, people will tell you to search, but, some basics are Cold Air Intake (CAI), Exhaust, Plugs / Wires, DHP. Then get into nice stuff like Headers, get something so its not N/A, mainly a supercharger. Good luck modding.

03-31-2005, 02:44 PM
thermostat also while you are in there, you wont want to do it otherwise

03-31-2005, 02:52 PM
Yea, thats a good one, and, if you install it yourself, it is a pretty long job for something that is only $11, but, its worth it.

03-31-2005, 03:07 PM
Well, you can port and polish the upper and lower manifolds while they are off the car. My advice is, that if your serious about modding the car and being real fast... get the heads ported and polished while you have the car apart. RSM sells P&P'd heads if you don't have a local place that will do it. You can also upgrade valvetrain components if you're so inclined, but most don't feel this is that important.

So, P&P heads, upper intake, and lower intake. And if you've got the motor apart, you might as well get headers on it while your working, you'll already have all the stuff removed to get to them. The thermostat is also a good mod since you're already there, I regret not changing mine while I had the chance to do it easily. PFYC sells the appropriate one.

04-01-2005, 08:56 AM
When port and polishing the heads/manifolds what does that mean specifcally? Do I replace any valvetrain parts after doing this? What thermostat should I be looking for?

04-02-2005, 05:43 AM
You should look for the Hypertech 180 degree thermometer. Supposedly, the 160 isnt the best for our cars (I didnt even know they made a 160 for our cars). If you go to PFYC.com, you can go under Grand AM 99-04, Then go to "Under The Hood", and it is the first thing on the right hand column. What it does is turn you engine fans on to keep the engine and collant at a lower temperature level.
For the P&P, I am not to sure. I know that it is not usually a first mod. It is going to cost anywhere from $1,000 and upward, mostly because you have to take a large portion of the engine completly out. The only thing you will need usually is a new gasket. Talk to the people at a body shop and they can give you price/details/things that you will need.

04-02-2005, 05:52 AM
Sorry, I actually didnt tell you what it means specifically. When you Port and Polish, you are increasing the intake side diameter while also removing and casting defects from the runner surfaces. Sometimes, you also enlarge and polish the area around the valves. It mainly increased air flow throughout the head, creating a better burn because of more air going in. It will improve power, and, if you dont abuse your new power, give you better gas mileage.
I didnt really explain the pricing to well either. The job itself will usually cost around $500-$800, although, the labor of taking out the engine compenents, adding a new head gasket, and reinstalling everything is going to run you up over $1,000. Its not a one day job either. Depending upon where you go, it will be 2 - 5 days.