Set of cogs to gear up your 8V GTI in 5th gear
- Mike E (uk)
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Set of cogs to gear up your 8V GTI in 5th gear
I am having a bit of a BX parts clear out this season,
18 months ago, I modified my 16V gearbox to improve top gear cruising.
I am VERY pleased with the result, and in the process I got a spare set of 16V gearbox 5th speed cogs.
These are what you need to gear up an 8V GTI in a similar way.
The 8V engine has more torque at lower speeds than the 16V, so the mod saves you even more rpm than on the 16V car.
This reduces noise and saves fuel, making a more relaxing motorway drive.
A handy thing is that you do not need to remove the gearbox to do this.
The cogs are accessable under the n/s wheel arch.
For a GTi this gives:
was 21.6mph per 1000rpm
modified 24.7 mph per 1000rpm
70mph was 3237rpm, modified is 2832rpm
Mike
18 months ago, I modified my 16V gearbox to improve top gear cruising.
I am VERY pleased with the result, and in the process I got a spare set of 16V gearbox 5th speed cogs.
These are what you need to gear up an 8V GTI in a similar way.
The 8V engine has more torque at lower speeds than the 16V, so the mod saves you even more rpm than on the 16V car.
This reduces noise and saves fuel, making a more relaxing motorway drive.
A handy thing is that you do not need to remove the gearbox to do this.
The cogs are accessable under the n/s wheel arch.
For a GTi this gives:
was 21.6mph per 1000rpm
modified 24.7 mph per 1000rpm
70mph was 3237rpm, modified is 2832rpm
Mike
Last edited by Mike E (uk) on Sun Dec 18, 2005 11:29 am, edited 1 time in total.
- sleepy0905
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- sleepy0905
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I doubt if dropping the revs in 5th will save anything on a 1.9D engine - in fact the opposite may well be true as the thing won't have the power to pull 5th most of the time and you will probably have to use 4th most of the time.
Remember that a diesel engine cuts off all fuel on the overrun and is at its best on part throttle.
The torque of the 1.9D is about 90 lb/ft and the 1.7 turbo engine is 133 lbft which is how it pulls the very tall 5th gear.
jeremy
Remember that a diesel engine cuts off all fuel on the overrun and is at its best on part throttle.
The torque of the 1.9D is about 90 lb/ft and the 1.7 turbo engine is 133 lbft which is how it pulls the very tall 5th gear.
jeremy
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- Mike E (uk)
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Thought not. What you have done is introduced a big hole between fourth and fifth, lost your fifth gear acceleration and reduced your top speed by a couple of MPH as the engine won't pull peak RPM. Having to drop to fourth to overtake and changing up later to avoid the hole will mean that you don't save any fuel either although I concede that the car may be quieter.
- Mike E (uk)
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5th gear mod.
Hi Tom,
My 'No' was tongue in cheek.
But it does drive perfectly well.
Perhaps you think I have changed the ratios more than I actually have.
rpm is only reduced by 13% in 5th.
If you have not driven a BX16V with this exact modification, you are welcome to take mine for a spin and try it out. Are you going to the Feb. meeting?
I am not saying that Citroen got it horribly wrong, only that their priorities must have been a bit different. Their car will accelerate a bit faster in 5th. But to me, this is less important than cruising ability on A roads and motorways.
There is no 'hole' between 4th and 5th. The change is perfectly normal.
Top speed may be reduced from 133 to 130mph perhaps, but I never will drive that fast.
You may be surprised by how well it works. I was!
It was only after I had done the mod and driven it, that I was convinced I had done the right thing.
I was afraid of a 'hole' appearing too, so I took a bit of a chance that I would have to swap it all back again.
To overtake you will normally drop to 3rd or 4th gear anyway, because the 5th gear is an overdive.
MPG is improved, I have recorded 42. That was motorway driving at 70ish. Before I would have expected about 38mpg. That surprised me, but typical short journeys will give no saving.
Happy New Year,
Mike
My 'No' was tongue in cheek.
But it does drive perfectly well.
Perhaps you think I have changed the ratios more than I actually have.
rpm is only reduced by 13% in 5th.
If you have not driven a BX16V with this exact modification, you are welcome to take mine for a spin and try it out. Are you going to the Feb. meeting?
I am not saying that Citroen got it horribly wrong, only that their priorities must have been a bit different. Their car will accelerate a bit faster in 5th. But to me, this is less important than cruising ability on A roads and motorways.
There is no 'hole' between 4th and 5th. The change is perfectly normal.
Top speed may be reduced from 133 to 130mph perhaps, but I never will drive that fast.
You may be surprised by how well it works. I was!
It was only after I had done the mod and driven it, that I was convinced I had done the right thing.
I was afraid of a 'hole' appearing too, so I took a bit of a chance that I would have to swap it all back again.
To overtake you will normally drop to 3rd or 4th gear anyway, because the 5th gear is an overdive.
MPG is improved, I have recorded 42. That was motorway driving at 70ish. Before I would have expected about 38mpg. That surprised me, but typical short journeys will give no saving.
Happy New Year,
Mike
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