[Graham]

I have a 71 GT, with a rebuilt motor but would like a little more power, I have searched the forums but haven't found what I'm looking for. Is there a small turbo charger out there that can bolt on without a lot of modifications. I don't want to race the GT or blow anyone's doors off, I just want a little more power from the 1.9.

Any suggestions?

 

[nobody]

A turbo on A GT is no small add on with the limited space involved. Then again the old saying still applies "speed is money, how fast do you want to go?"

If you could give some details like is the motor stock would help or how much you want to spend. An Idea of how much more power you want would help as well.

 

[madhatterpdc]

Well, there are a lot of ways to answer that question. Start off by reading RallyBob's Turbo thread here,

http://www.opelgt.com/forums/showthread.php?t=3316&highlight=quest+carlisle

You mentioned that you didn't want to blow anyone's doors off, so read Bob's build-up keeping in mind that a good selection of parts will provide an appropriate level of power. I'd venture a guess that the WRX turbo (for the reason stated in Bob's thread) at 7-8 psi will give a healthy improvement in power, spool quickly and not be to abusive to components. But don't ever skimp on quality or durability, unless you like fixing more than driving. There is no way around custom fabricating the turbo header, you or a competent welder are going to have to do this just like Bob did... except if this is going in a GT you will not be able to copy his design even a little, there isn't close to enough room. I am a much bigger fan of some form of fuel injection for forced induction motors. Carbs just aren't sophisticated enough to handle boost well. Don't forget all the electronics. A nice ECM isn't cheap, but you will be able to adjust all your fuel, mixture, ignition and boost functions with one or two components.

I'm going to be sticking with carbs for my motor, but believe me, I would love to be able to afford to fine-tune my car using a laptop on the front seat.

 

[kwilford]

Graham,

I moved this to the "Engine Performance" forum (the GT forum is ONLY for items that aren't better suited to one of the Technical Forums). Have a look around; there are some great threads here on the topic. Read ALL of RallyBob's threads (that could take most of the winter!). Especially read:

http://opelgt.com/forums/showthread.php?t=3914

and

http://opelgt.com/forums/showthread.php?t=2305

There isn't a real quick answer, and turbocharging is CERTAINLY not one of the easiest, nor most cost effective, solutions. And ANY of the solutions will cost $$. With increasing costs for decreasing returns.

As Dave (nobody) has asked, what is the status of your current engine:

1) Carb: Solex or Weber, 32/36 DGAV or 38 DGAS, or SSD (Single Side Draft) 45 DCOE, or Twin Side Drafts 40DCOE's or DCOM's?
2) Engine: Low or high compression pistons? Stock diameter or oversize (can get 2.0 litres with bigger pistons)? Stock crank or "stroked" (can get 2.4 litres with big pistons and stroked cam)
3) Head: Stock or higher lift/longer duration cam? Stock valves or oversize?
4) Ignition: points or electronic (Pertronix or Crane or ?)
5) Intake: Stock filter or K&N or pancake? Cold air intake or hot? Stock or ported? Radical or "street"? Margarine or butter (just checking to see if you are still paying attention!)

I am being a bit facetious about some of the questions, because you clearly don't have a 2.4 with twin DCOE's and a high lift cam and roller rockers. As you can see, the sky (and the cost) is the limit.

 

[nobody]

To be honest the timing of this is pretty ironic. I have been goofing off today and building the first bolt it up and go system. I have alot of parts and no sign of another car so I was rebuilding and modifying twins. Next is a bolt up Turbo for a GT, kinda funny huh? I figured I'd put it in a sort of hope chest for a possible second car when I finish it.

 

[tekenaar]

Stroked cams?

Graham,

I moved this to the "Engine Performance" forum (the GT forum is ONLY for items that aren't better suited to one of the Technical Forums). Have a look around; there are some great threads here on the topic. Read ALL of RallyBob's threads (that could take most of the winter!). Especially read:

http://opelgt.com/forums/showthread.php?t=3914

and

http://opelgt.com/forums/showthread.php?t=2305

There isn't a real quick answer, and turbocharging is CERTAINLY not one of the easiest, nor most cost effective, solutions. And ANY of the solutions will cost $$. With increasing costs for decreasing returns.

As Dave (nobody) has asked, what is the status of your current engine:

1) Carb: Solex or Weber, 32/36 DGAV or 38 DGAS, or SSD (Single Side Draft) 45 DCOE, or Twin Side Drafts 40DCOE's or DCOM's?
2) Engine: Low or high compression pistons? Stock diameter or oversize (can get 2.0 litres with bigger pistons)? Stock crank or "stroked" (can get 2.4 litres with big pistons and stroked cam)
3) Head: Stock or higher lift/longer duration cam? Stock valves or oversize?
4) Ignition: points or electronic (Pertronix or Crane or ?)
5) Intake: Stock filter or K&N or pancake? Cold air intake or hot? Stock or ported? Radical or "street"? Margarine or butter (just checking to see if you are still paying attention!)

I am being a bit facetious about some of the questions, because you clearly don't have a 2.4 with twin DCOE's and a high lift cam and roller rockers. As you can see, the sky (and the cost) is the limit.

Well now, that's a new one on me! Exactly how does one go about stroking a cam?

Think he meant crank . . . Keith?

 

[Bosco2]

I have a newly rebuilt 69 engine in my 73 GT. I added a sprint exhaust manifold and 2" exhaust piping with a magna flo muffler. I also opened up the intake manifold (and heat shield) to match the 32/36 dgv carb which I re-jetted properly (or much closer to properly than it was). Finally I added a Crane pointless ignition. These changes didn't create a huge dollar expenditure and were very easy but they definatly improved the performance, without decreasing (and probably increased) dependability. I also plan to ditch the carb mounted air filter and either fabricate a cold air intake or adapt the stock air cleaner to the weber to help perfomance here in Nevada during the summer months.

 

[tekenaar]

Cold air . . . cold fuel . . .

I have a newly rebuilt 69 engine in my 73 GT. I added a sprint exhaust manifold and 2" exhaust piping with a magna flo muffler. I also opened up the intake manifold (and heat shield) to match the 32/36 dgv carb which I re-jetted properly (or much closer to properly than it was). Finally I added a Crane pointless ignition. These changes didn't create a huge dollar expenditure and were very easy but they definatly improved the performance, without decreasing (and probably increased) dependability. I also plan to ditch the carb mounted air filter and either fabricate a cold air intake or adapt the stock air cleaner to the weber to help perfomance here in Nevada during the summer months.

Yes, yes, yes!!! You will be amazed at how much difference this makes in the performance of the engine.

If you still have a metal fuel line underhood, have you wrapped it with 1/4" plastic split wire loom to prevent radiant heat soak? Get rid of your metal can fuel filter while you're at it and replace with plastic see-thru type!

 

[kwilford]

Think he meant crank . . . Keith?

Um, well, ah, YES. It was a long post, and I was thinking cams when I meant cranks, so I typed cam instead of crank. But thanks to Otto's eagle eyes, I was found out.

 

[Bosco2]

I have the fuel line wrapped in the plastic wire loom and had little to no heat soak problems this past summer. I still have the metal can fuel filter as i haven't seen a plastic one that has the return line on it (1973).

 

[baz]

bosco look for a nissan/datsun filter they have a return on them here


opel gt the original sheep in wolfs clothing

 

[Bosco2]

Thanks for the tip, Baz.