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Weird question, but how is a 1.8lt injected engine meant to *feel*?

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I got my 1993 Cabriolet some years ago and it was in rough shape - whilst the body was in great condition it had not been driven in a very long time and the running gear was (seemingly) all original (read: no new shocks, springs or ball joints in decades).

Over the years I've pieced things together, bit by bit, and now the car is running well. There's still a few things to fix up, but overall I am confident with how the project is going (note too that I took this up as a hobby with no mechanical knowledge or background).

However, there is a concern I have - the car feels weak at the top end of the rev range. Above 3,000rpm there doesn't feel like any extra torque at all. That's different to most modern (or, rather, 90s) cars I've driven where there is at least something up there.

I also realised I've never actually driven a properly fixed up Mk1. In fact, I've never driven any other Mk1 but my own. I'm in Australia and these things are quite thin on the ground, so I have no idea if this is what it's meant to be like. I know it's not a fast car, but it does feel a quite lacking above 3k.

Is this how it's meant to be? Or is there something else I maybe should pay some attention to?

Extra information. This is what I've replaced on the car, engine-wise:

 * New plugs and leads
 * New battery and alternator
 * New fuel filter and injector lines
 * New fuel and lifter pumps
 * Fixed a few vacuum leaks
 * Thermostat and radiator flush

Also:

 * The car doesn't really struggle cruising or in traffic - it keeps up with other cars fine, there's just no 'punch' (even a little one) if I floor it.
 * If I am lead-footed with the accelerator it seems to drink a lot more fuel but with little performance increase.

Thanks, any advice or input is appreciated!
 

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What engine have you got in there, the 112bhp DX K-jet engine or a de-tuned version with a CAT which they sell in USA etc?

Above 3,000 rpm mine pulls harder/faster then below 3000 rpm, up to about 5500 rpm then it starts to drop off till the rev limiter comes in.
To over take another car I drop down to a gear where I'm at 3000 rpm ish before going for it…

Could be your car is running to weak as it's losing the mixture higher up the rev range or the timing is out. What fuel are you using?

About 2% CO is a good place the start with the mixture and see it that helps.

I did find fitting a 4,2,1 exhaust manifold helped the top end grunt as the original C clip/toilet bowl type manifold seemed to hold things back.

But I would check the mixture/tuning/timing 1st before spending time and money upgrading the exhaust manifold.

1988 Mk1 Golf GTi Cabriolet 1.8cc DX, K-jet. Daily drive. 290,000 miles and counting
1978 Mk1 Scirocco GLS 1.6cc FR, Webber carb. Weekend toy.

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mark1gls said

What engine have you got in there, the 112bhp DX K-jet engine or a de-tuned version with a CAT which they sell in USA etc?

Above 3,000 rpm mine pulls harder/faster then below 3000 rpm, up to about 5500 rpm then it starts to drop off till the rev limiter comes in.
To over take another car I drop down to a gear where I'm at 3000 rpm ish before going for it…

Could be your car is running to weak as it's losing the mixture higher up the rev range or the timing is out. What fuel are you using?

About 2% CO is a good place the start with the mixture and see it that helps.

I did find fitting a 4,2,1 exhaust manifold helped the top end grunt as the original C clip/toilet bowl type manifold seemed to hold things back.

But I would check the mixture/tuning/timing 1st before spending time and money upgrading the exhaust manifold.

Thanks, this is good advice.

Yeah the timing and mixture has, as far as I know, never been touched so that's a good place to start.

I don't know what engine I have (other than a 'JH1'). What's the best way to tell? I'd assume it's not the American version as it's a RHD car - probably the same version as the UK.

As for fuel I just use regular 92 octane.

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Yes the JH is a de-tuned engine to meet lower emissions, so it's 90 BHP compared to the 112 BHP DX engine.

I think that is why you can run on 92 RON petrol while the DX is meant to run on 98 RON petrol.

You can no longer buy 92 RON petrol in the UK (used to be 2 star petrol) only normal unleaded at 95 RON or super unleaded which is between 97 to 100 RON depending on which brand of super you use.

Engine code info.

8 valve engines - OEM, tuned + race outputs | Club GTI


I'm not sure on what the CO needs to be on your engine as I don't know much about them.

A tune up could help?

1988 Mk1 Golf GTi Cabriolet 1.8cc DX, K-jet. Daily drive. 290,000 miles and counting
1978 Mk1 Scirocco GLS 1.6cc FR, Webber carb. Weekend toy.

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The only real way is to put it on a dyno and get some figures. They're not quick compared to modern cars tbh. 

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I have a 1992 cabrio in NZ which according to the build sticker/ VIN is for the Aus market. It has DX engine (GTi). It always feels punchy right across the rev range and still feels quicker out of the blocks than most modern normally aspirated cars of say 1.6L.

Based on what you have already replaced and described I would also check if your vacuum advance on the distributor works. A good tune up will most certainly make a big difference after so many years.
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