911R inlet manifolds
Moderator: Bootsy
911R inlet manifolds
Having received a COVID grant earlier in the year I’ve been investing in my product range.
Here is my first offering, a Pair of 96 mm tall 911R inlet manifolds
Recast in Aluminum to suit 40mm carbs
These were my machining trial, and identified an area on the pattern that needed to be adjusted, which has now been done.
On these ones I had to use a die grinder so two of the nuts and washers will fit.
They have been trial fitted and work with the std Weber linkage
£295
Also available to suit 46mm carbs
I am developing a variant to include efi or mfi injectors in the base of the manifold, along with 90 mm high Weber pattern high butterfly throttle bodies, which will eventually become a full efi kit in the near future
Here is my first offering, a Pair of 96 mm tall 911R inlet manifolds
Recast in Aluminum to suit 40mm carbs
These were my machining trial, and identified an area on the pattern that needed to be adjusted, which has now been done.
On these ones I had to use a die grinder so two of the nuts and washers will fit.
They have been trial fitted and work with the std Weber linkage
£295
Also available to suit 46mm carbs
I am developing a variant to include efi or mfi injectors in the base of the manifold, along with 90 mm high Weber pattern high butterfly throttle bodies, which will eventually become a full efi kit in the near future
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Last edited by Madjad on Thu Apr 29, 2021 5:32 pm, edited 1 time in total.
Westbound Restorations since January 19
Re: 911R inlet manifolds
Preview of the injector boss
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Westbound Restorations since January 19
- MikeB
- Put a fork in me, I'm done!
- Posts: 1913
- Joined: Thu Aug 07, 2008 11:13 pm
- Location: N. Ireland
Re: 911R inlet manifolds
Hi what is the internal diameter at the cylinder head end, please?
Cheers
Mike
RS Rep 3.0 on Webers
Mike
RS Rep 3.0 on Webers
Re: 911R inlet manifolds
35mm as cast with 40 carbMikeB wrote:Hi what is the internal diameter at the cylinder head end, please?
39mm as cast with 46 carb
Obviously they can be bored, or left as cast so they can be matched to your head
Also forgot to say, I can also cast them in magnesium!
Westbound Restorations since January 19
Re: 911R inlet manifolds
Apart from looking good what do these manifolds do to engine performance? Do they only work with certain types of cam?
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
Philip
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- Nurse, I think I need some assistance
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- Location: Worcs/W Mids border
Re: 911R inlet manifolds
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Engines with more 'aggressive' cams - like the 911R/906 - which have lots of overlap, can suffer from fuel reversion at low to med revs where pulses up the intake hit a certain resonance & create a cloud of droplets floating above the mouth of the carb.
The 911R/906 manifolds at 98mm tall compared to the std 2.0 Weber manifolds which were 68mm had the effect of altering the frequency of the pulses meaning that they no longer matched that resonance & the cloud of droplets disappeared ...
.
Engines with more 'aggressive' cams - like the 911R/906 - which have lots of overlap, can suffer from fuel reversion at low to med revs where pulses up the intake hit a certain resonance & create a cloud of droplets floating above the mouth of the carb.
The 911R/906 manifolds at 98mm tall compared to the std 2.0 Weber manifolds which were 68mm had the effect of altering the frequency of the pulses meaning that they no longer matched that resonance & the cloud of droplets disappeared ...
.
Andy
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
-
- Nurse, I think I need some assistance
- Posts: 16928
- Joined: Wed Nov 12, 2003 10:48 pm
- Location: Worcs/W Mids border
Re: 911R inlet manifolds
.
Basically the end result was improved torque/drivability at low/medium revs ...
.
Basically the end result was improved torque/drivability at low/medium revs ...
.
Andy
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
Re: 911R inlet manifolds
The production manifolds will be 98mm tallLightweight_911 wrote:.
Engines with more 'aggressive' cams - like the 911R/906 - which have lots of overlap, can suffer from fuel reversion at low to med revs where pulses up the intake hit a certain resonance & create a cloud of droplets floating above the mouth of the carb.
The 911R/906 manifolds at 98mm tall compared to the std 2.0 Weber manifolds which were 68mm had the effect of altering the frequency of the pulses meaning that they no longer matched that resonance & the cloud of droplets disappeared ...
.
Westbound Restorations since January 19
Re: 911R inlet manifolds
Working on fitting the injectors
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- 25863211-EF48-4784-AE19-189E9BDCE926.jpeg (32.3 KiB) Viewed 595 times
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- 43BC822D-38A8-4A8F-8937-CC9396600269.jpeg (38.22 KiB) Viewed 595 times
Westbound Restorations since January 19