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Best gains for dropping $2000 into a GTP

MidnightSpecial

New member
Ok guys I just sold my 1970 Dodge Polara coupe (383) to fund my near future GTP build. I want to get as much power and speed out of my grand prix as I can without going into the engine. Here is my wild plan, let me know if I should maybe reconsider parts of it.

I have a 2000 GTP coupe with 165XXX miles on it. Only mods this car has is a 4" FWI, 3" bolt in downpipe with no cat, rear 02 emulator, alternator voltage booster. This car is not my daily driver so driver friendliness does not concern me. It is for summer cruising/racing only.

I plan on buying the

1. W-body store stage 2 intercooler kit with the intercooler fuel rails, and ported lower intake manifold.

2. 180* thermostat

3. aeroforce Interceptor scan gauge

4. W-body store modular pulley system

5. Tuned PCM from Overkill powersports

Ok so here are some of my questions,

1. With these mods what supercharger pulley size should I start out with? The description on the w-body store website for the intercooler says I can run a 3.0 without knock retard but I was thinking about going to a 3.1 to be safe. What do you think?

2. What else do I need besides the Intercooler kit, lower intake manifold, and modified fuel rails to install the intercooler?

3. How hard is it to install the aeroforce scan gauge and is anything else required to do so?

4. What type of gains as far as HP, 1/4 mile time, and 0-60 times should I expect with the above mods?

Thanks for any info fellow 3800 motorheads! :th_jester:
 


I hate to say it but you'll need a new transmission soon if you go that route. With 165,000 I'd say you need to get one anyways. As its not your DD I have a feeling that you'll be beating on it more than usual. Look around on here and you may be able to find a new used one thats been beefed up. I was able to get one for $400 in great condition. Then you can focus on doing a few mods. While you get a new transmission you should either go for 3.29 or 3.69. 3.29 seems to be the sweet spot but 3.69 is more of the tire roasting gearing people get.
 
Just turbo it and be done with it. You can sell those existing mods for some $$.

I havn't actually bought any of these mods yet, right now I am just trying to figure out what my best route of action is. I would turbo it but I am more interested in keeping it supercharged. There are plenty of turbocharged rice burners around here and I want to keep mine as american as possible. lol :th_peaceout:

P.S. The only turbo kit I have seen for this car under 2500 is the one on ZZP and it sounds like I would need more than just that kit to complete the job.
 
Nope, just need the kit. You will go supercharged and find you want turbo later. Turbo isnt rice, body kits and no turbo is rice.
 
I am more interested in keeping it supercharged. There are plenty of turbocharged rice burners around here and I want to keep mine as american as possible. lol

Grand National's are pretty damn American lol

If you want to go fast then turbo is the way to go, if you just want a little faster than stock then stick with the blower.
 


You'd be surprised how many "american" cars are going with turbocharged V8's.

Low end grunt plus top end power = win 100% of the time.
 
That's ok let him think what he wants and enjoy being slower then every turbo civic he runs into.

I love this red neck outlook on cars make me laugh :th_laugh-lol3:

Ignorance is Bliss right lol

FYI there is a turbo kit on cgp going for 2k and you can prob talk him down on it too.
 
I would ditch the aeroforce gauge and the canned tune, and get a tuner, you can dial it in much better that way and you will avoid the rumored boom boom that goes with the canned tunes.

I am shocked to not see headers on that list, had you been a couple days earlyer you could have gotten in on the group but of the speed daddy headers and save ya 60 bucks.
 
I would ditch the aeroforce gauge and the canned tune, and get a tuner, you can dial it in much better that way and you will avoid the rumored boom boom that goes with the canned tunes.

I am shocked to not see headers on that list, had you been a couple days earlyer you could have gotten in on the group but of the speed daddy headers and save ya 60 bucks.

Yup and been scammed into buying OBX's.
 


To me the spirit of a GTP comes from it being supercharged. Plus I have absolutely no knowledge of turbos. The only things I have ever heard about them is how much of a headache they can be.

I'm assuming that by adding this $2400 turbo kit and getting more boost than I can get with a intercooled supercharger that I would have the exact same issues as I would with having too much boost from a supercharger. Think about this, I could Whipple charge it and get way more performance than a basic turbocharging kit, but then again that would be more money yet. It just depends on how much money you want to spend and I'm not willing to stick all that much more into this car. There are plenty of N/A cars that will smoke turbocharged and supercharged cars. Its not like its impossible to have a mean GTP without going turbo. I'm not looking to stomp every single car I run into. Thats stupid to think that you will unless you have some unlimited source of money or plan on building up your car over a period of 20 years.

In addition to that whats the point of having a GTP if your not gonna have it be supercharged?
 
To me the spirit of a GTP comes from it being supercharged. Plus I have absolutely no knowledge of turbos. The only things I have ever heard about them is how much of a headache they can be.

I'm assuming that by adding this $2400 turbo kit and getting more boost than I can get with a intercooled supercharger that I would have the exact same issues as I would with having too much boost from a supercharger. Think about this, I could Whipple charge it and get way more performance than a basic turbocharging kit, but then again that would be more money yet. It just depends on how much money you want to spend and I'm not willing to stick all that much more into this car. There are plenty of N/A cars that will smoke turbocharged and supercharged cars. Its not like its impossible to have a mean GTP without going turbo. I'm not looking to stomp every single car I run into. Thats stupid to think that you will unless you have some unlimited source of money or plan on building up your car over a period of 20 years.

In addition to that whats the point of having a GTP if your not gonna have it be supercharged?

You could buy like 10 of these cars for how much it costs to whipple one, just stick with the M90 if you don't want a turbo.
 
Thats definetly what I plan on doing. These guys make it sound like a turbo is such an easy way to outperform a supercharger. Turbokit- $2500 with shipping, plus everything else you would need to do it right. I'm guessing $3000 is a very cheap estimate for going turbo. I'm not even thinking about spending that kind of money. If I was I would much rather just sell my GTP, buy another old mopar, build up a bad ass 440 and smoke all kinds of turbocharged cars. My Idea of intercooling seems like the smartest way to start slowly modding my GTP. Who knows maybe some day I will go hog wild and pull the engine, build it up tougher, build up a tough transmission, and do every possible thing you can do to it to make HP. But for now I just want to be able to beat the guy down the street if you know what I mean.
 
There are plenty of N/A cars that will smoke turbocharged and supercharged cars.

Generic much lol?

You could buy like 10 of these cars for how much it costs to whipple one, just stick with the M90 if you don't want a turbo.

Nah its actually not too bad to throw a whipple on if you can find the kit. Usually around the 2-3k mark for the ax140 kit.

You can also do a MP112 kit too. Ive seen em go for around 2k more or less.



I will say this midnight you are the model for every domestic > import redneck out there dude lol. Oh btw no S/C GP will ever make more power then a Turbo setup. Just saying ;)

You asked for the best gains while dropping 2k. Guess what you will make the most power for 2k on a turbo kit. They can be had for that price all over the forums.

Your deff right about the money aspect but I will say this if you shop around you'll find deals everywhere. Ive saved probably 70% off what everything would of cost new for my entire setup.
 
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Generic much lol?

I'm just trying to say that a turbocharger isn't the only way to make serious power. I may be an oddball for thinking like this but I would like to make something different than what the crowd is making. Just to be different. Sounds like turbochargers are all the rave these days. Last time I was on here barely anyone was talking about them. Then something else will come out that will be better than turbocharging. How about a procharger? All the benefits of a turbocharger and a supercharger combined.
 
^^Hardly...it is still a belt driven piece of FI that uses power off of the motor...even though they tend to less parasitic...I think that they are designed for big engined cars only...they used to make a PC setup for the GP called the Novi 1000 and 2000...not anymore.

For the money though...a Whipple or MP112 build isn't worth it...you can go turbo and make 100+ more horse for the same price...when I talked to Paul about the Whipple build a couple years ago I know with the parts (even with him getting some for me since he knew a few people) was gonna sit well over $4K for everything including the IC, injectors, headers...blahblahblah.

2K?

Intercooler/Tiny Pulley/42.5 injectors/Headers/Ported Blower&LIM/Cam or Rockers...then save for a transmission...
 
Again, money. A turbo kit is good to go out of the box, will consistently make more power than a m90 setup, and will net you better gas mileage. Turbos sound alot meaner than superchargers, just sayin.
 
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