How much would it cost to buy a faster engine? Where can you buy them? And any other info yall can help me with about putting and buying a new engine to be installed in a gt would be much appreciated......thanks.
There's a limit to how much motor fits in the engine compartment. As mentioned earlier, the engine protrudes into the interior compartment of the car - your feet actually end up between the number 2 & 3 cylinder!
Just about every Tom, Dick, and Harry that's ever seen a GT thinks, "Gee, that car would be REALLY cool with a hot V8 or race motor!" Some actually go so far as to buy the car and motor - then they find out it's like trying to fit ten pounds of crap into a five-pound bag. Much metal surgery is required to get a big motor into that teeny little hole...
Assuming you've managed to do it, (some have), then you have to improve the remainder of the drivetrain (transmission/rear end) along with braking and suspension systems. After you're all done, about the only thing that's stock is the roof and doors.
Okay, after saying all that - there are some later larger displacement bolt-in engines available from Opel parts suppliers. After adding in the extra pieces needed to make the bolt-in engine work, you'll drop about $4000 - above and beyond the cost of the car. The result? you'll be able to run with some of the local fart-tip crowd, but don't expect to suck anyone's headlights out.
Engine technology has come a LOONG way since the Opel was built - unfortunately this technology is very difficult to adapt to an Opel. there's no easy road when you're dealing with a 30 year-old car that was left of center on the day it was born!
I really dont want to put a huge engine in it....I just want to put a big enough engine to where i can make top speed around 125 and be able to drive it 75-80mph comfortably. Where the engine isnt straining. So you are saying that will cost me upwards of 4000 dollars to do?
The first four will set you back about $1200, and boost HP to the rear wheels by approx 20%. The last one gives you an overdrive gear, dropping hwy RPM. All the bits to fit a Getrag will set you back about $1200, too - the total? $2400.
Opel gearing is such that 50 RPM = 1 MPH using the standard rear end gearing (3.73:1). This means an Opel with a 4 speed manual trans is turning 4000 RPM (UPM for us Opel geeks) at 80 MPH.
The Opel motor is a darned robust piece - a LOT more durable than some of the modern motors. As a result, an Opel is pretty happy at these elevated RPM's for extended periods of time. I've done the LA- Vegas and the LA - Phoenix runs several times in a stocker Opel running 80-85 MPH. A stocker Opel GT will top out real close to 120 MPH and return 30+MPG at 70 MPH. Dunno what the 5 speed turns in for MPG, but the 5th gear drops engine speed to a little over 3500 RPM at 80.
soo - you really don't need the big motor - just some bolt-ons and a fresh 5-speed.
Don't forget about a ported Intake Manifold. Just ask those that have one... makes a big improvement to one of the weakest links in HP chain. It'll make more difference than a header.
Also, you'll want to start with the high compression engine. If you're gonna mess with the cam, then you might as well as opt for bigger valves too. At LEAST install 42mm intake valves.
You are not askin' for anything that you can't get out of an OPEL ! All the info is in the archives of this list and the ClassicOpels Group. All it takes is doing a complete search of the topics you're interested, print everything out, catalogue it all and then read every post about 10 times. From there you can start to combine the information into a single spread sheet..... Like I'm doing .
Good Luck, and don't be afraid to ask lots of questions.
Hopefully you have the early higher compression motor?
Start with a Weber 38 DGAS and a ported intake manifold. RallyBob wrote a great article on this a few years back. If you plan ahead and have everything you need before you start you should be able to easily pull this off in a weekend. Then go down to your local muffler shop and have them install a 2" exhaust (starting where the head pipe merges) and a decent flowing muffler. These three things will make a HUGE improment in the performance of your engine. You can then sit back and think about whether or not you want/need to go any further. If yes, read EVERYTHING RallyBob has said on this list and Robert Legere(same guy) has said on the classicopels list...and then read it again. It may take you a full day but you'll learn more than you likely would have over a years time getting your info someplace else. It will then all be clear