Long duration cams and why they work (By panic mechanic)

1hotTT
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Re: Long duration cams and why they work (By panic mechanic)

Post by 1hotTT »

Compression comes in to the equation way later than many of us think?

Bleeding compression is direct in relation to:
1) Head design
2) Piston design
3) Valve angle
4) Type of fuel

Most of all would be density of the mixture or coast or at altitude, turbo and or nos, methanol or alcohol...........etc...etc....
Ripjaw8520
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Re: Long duration cams and why they work (By panic mechanic)

Post by Ripjaw8520 »

I hate to ask a unrelated question. But i have a polo1.6 2005/06 BLM motor. Now im chaning the rear main seal. And obviously this specific seal has the pickup. What im asking is. I need the red tag to measure where this pickup and all must be placed to start the car. Or if someone can send me a diagram and measurements. I'd really appreciate it. I bought a brand new seal from goldwagen and it came with sensor. Just need to set this thing so car will start. Please help
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missioner
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Re: Long duration cams and why they work (By panic mechanic)

Post by missioner »

Ripjaw8520 wrote:I hate to ask a unrelated question. But i have a polo1.6 2005/06 BLM motor. Now im chaning the rear main seal. And obviously this specific seal has the pickup. What im asking is. I need the red tag to measure where this pickup and all must be placed to start the car. Or if someone can send me a diagram and measurements. I'd really appreciate it. I bought a brand new seal from goldwagen and it came with sensor. Just need to set this thing so car will start. Please help
Use the search function. This has been covered before many times. If the search doesn't help you then Start a new thread and repost your question.

'87 Golf 1 Olde Skewl OEM+
cliffm
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Re: Long duration cams and why they work (By panic mechanic)

Post by cliffm »

As I see it, air has a mass. When you cause air to move, through a tube at a high velocity, then try and stop it or force it backwards, the air at the back of the tube, will still push in the same direction, compressing the air in the middle towards the stoppage, like a spring, until it all comes to a stop. The very reason why the author speaks of "long inlet tubes' so the weight of the remaining air in the long inlet tube continues pushing the "middle" air into the cylinder, even though the piston is trying to push it back out. That is what is meant by "Velocity" on normally aspirated engines. In a turbo setup, this is not an issue, because we are dealing with pressure, not vacuum. So it does not have to rely on the weight of the air to force the remaining air into the cylinder, the turbo does a better job.

I hope that makes it a bit clearer.

Cheers!
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gPhilipC
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Re: Long duration cams and why they work (By panic mechanic)

Post by gPhilipC »

I need some advice. I need to "de tune" my caddy because it changed form being a weekend toy to a daily driver. It has throttles 298 cam and 350cc injectors.

Ican i just install a standard/272 cam.or should i replace the injectors as well. Will the throttles work with smaller injectors?

The internals are stock. It has Spitronics Management. I assume i have to re dyno after words.

Thank you.
Ex Rides

VW beetle 1600
Yamaha RZ 350 YPVS Full racing spec motor
VW Beetle 1.8 Motor
Jetta 2 1.8 (Stolen)
Jetta 2 1.8 (was in a sad state when i bought it)
1998 BMW 235 TDS (Respect for the diesel)
VW Citi 1.3
VW Jetta 3
2007 Kawasaki Verses 650
1996 Nissan 1400 AKA "scrappy"

Current Rides

2005 VW 1.9tdi - decat, and tune...
2001 VW Caddy Utlilty - 2l, standard block and head, throttles, branch, free-flow, 298 cam, spitronics management.
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Re: Long duration cams and why they work (By panic mechanic)

Post by missioner »

gPhilipC wrote:I need some advice. I need to "de tune" my caddy because it changed form being a weekend toy to a daily driver. It has throttles 298 cam and 350cc injectors.

Ican i just install a standard/272 cam.or should i replace the injectors as well. Will the throttles work with smaller injectors?

The internals are stock. It has Spitronics Management. I assume i have to re dyno after words.

Thank you.
The 272 will help make it more civilized to drive in traffic, the injectors are not a problem as most of them prefer to run at lower duty cycles. Better for longevity of the injector.

Retuning is a must as you would want your tuner to also pay attention to the driveability of the car, which means they need to properly tune the partial throttle positions and adjust the map lower down in the rev range for actual road driving. This is opposed to a track toy that is permanent WOT.

I am not a tuning expert so in this case I suggest doing some homework to find someone who can get the results you are looking for.

I can't personally vouch for these guys but 8V Performance come well recommended by many on the forum, and are known Dictator guys.

Another to consider is Panic's Place. Stefan is an artist with a spanner and is reasonable with his pricing.

Both shops are in the East Rand and easily accessible from the N12. If it's far for you then perhaps ask for a referral to someone in your area.
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gPhilipC
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Re: Long duration cams and why they work (By panic mechanic)

Post by gPhilipC »

missioner wrote: Sun Feb 21, 2021 10:30 pm
gPhilipC wrote:I need some advice. I need to "de tune" my caddy because it changed form being a weekend toy to a daily driver. It has throttles 298 cam and 350cc injectors.

Ican i just install a standard/272 cam.or should i replace the injectors as well. Will the throttles work with smaller injectors?

The internals are stock. It has Spitronics Management. I assume i have to re dyno after words.

Thank you.
The 272 will help make it more civilized to drive in traffic, the injectors are not a problem as most of them prefer to run at lower duty cycles. Better for longevity of the injector.

Retuning is a must as you would want your tuner to also pay attention to the driveability of the car, which means they need to properly tune the partial throttle positions and adjust the map lower down in the rev range for actual road driving. This is opposed to a track toy that is permanent WOT.

I am not a tuning expert so in this case I suggest doing some homework to find someone who can get the results you are looking for.

I can't personally vouch for these guys but 8V Performance come well recommended by many on the forum, and are known Dictator guys.

Another to consider is Panic's Place. Stefan is an artist with a spanner and is reasonable with his pricing.

Both shops are in the East Rand and easily accessible from the N12. If it's far for you then perhaps ask for a referral to someone in your area.


Thank you for the advice. I am running Spitronics.

Traffic driving on a Monday morning with a 288cam is not a verry pleasant experience. Once on the free way however...
Ex Rides

VW beetle 1600
Yamaha RZ 350 YPVS Full racing spec motor
VW Beetle 1.8 Motor
Jetta 2 1.8 (Stolen)
Jetta 2 1.8 (was in a sad state when i bought it)
1998 BMW 235 TDS (Respect for the diesel)
VW Citi 1.3
VW Jetta 3
2007 Kawasaki Verses 650
1996 Nissan 1400 AKA "scrappy"

Current Rides

2005 VW 1.9tdi - decat, and tune...
2001 VW Caddy Utlilty - 2l, standard block and head, throttles, branch, free-flow, 298 cam, spitronics management.
Chris276deg
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Re: Long duration cams and why they work (By panic mechanic)

Post by Chris276deg »

I have a Vw 1.4i 8v
Bought a 276 high lift cam
After installing the cam and tightening the caps, the cam lobe is touching the cylinder head outside of the lifters
Chris276deg
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Re: Long duration cams and why they work (By panic mechanic)

Post by Chris276deg »

I have a Vw 1.4i 8v
Bought a 276 high lift cam
After installing the cam and tightening the caps, the cam lobe is touching the cylinder head outside of the lifters
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PapaJo
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Re: Long duration cams and why they work (By panic mechanic)

Post by PapaJo »

Chris276deg wrote: Sat May 20, 2023 10:18 pm I have a Vw 1.4i 8v
Bought a 276 high lift cam
After installing the cam and tightening the caps, the cam lobe is touching the cylinder head outside of the lifters
You will need to clearance (remove some material) in the areas where it is touching.
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