New 928 Headers with Merged Collectors
#16
I know with the right location for the holes, you could probably reasonably center the header over each 16v exhaust port. But I can't come to terms with that large of a transition right at the head. That much turbulence dumping small port into a bigger tube like that will probably (IMO) ruin all the scavenging action that was available...
And BTW: these 16v heads have been massaged a wee bit. Their ports are actually slightly larger than stock!
And BTW: these 16v heads have been massaged a wee bit. Their ports are actually slightly larger than stock!
#17
Any chance of mounting the headers backward (collectors pointing forward) for the purposes of getting a dyno reading?
That's the rub. I had every intention of running these headers on the engine dyno when I broke in my motor (pic below) and then was slapped in the head by the fact that the dynamoter occupies the very space the headers have to be in (duh). The 928 is a Torque Tube car, and the exhaust is aimed down the center line.
Rats. No engine dyno possible.
So - then chassis dyno results? Right. Imagine this; someone has to bring me a 32v 928 with stock MSDS headers on it so I can take it to the chassis dyno for the baseline. Then I would have to swap out the early open-collector header for the merged-collector header, and dyno again.
That situation has not yet presented itself, so I do not have any dyno charts for you.
Rats. No engine dyno possible.
So - then chassis dyno results? Right. Imagine this; someone has to bring me a 32v 928 with stock MSDS headers on it so I can take it to the chassis dyno for the baseline. Then I would have to swap out the early open-collector header for the merged-collector header, and dyno again.
That situation has not yet presented itself, so I do not have any dyno charts for you.
#19
Update on 16V headers with merged collectors
Doing a count of 16v headers in stock - we find there aren't that many... so development has begun today on transferring the merged collector system over to the 16v headers too.
I'd like to do a before-and-after dyno pull for these new headers.
So this is a call out to someone who has MSDS headers currently installed on their 16v 928 and would like a "free" upgrade. Bring us your car and we will do a baseline dyno pull on it. Then we will swap out your Gen 1 headers for the new Gen 2 headers with merged collectors, and dyno it again.
Here are your costs: The headers will be no cost to you. You will not have to pay for the dyno time either. You will be charged 50% shop labor rate to swap the headers.
Let me know!
PS: same deal is available for somebody with a 32v 928 and a set of Gen 1 MSDS headers installed....
I'd like to do a before-and-after dyno pull for these new headers.
So this is a call out to someone who has MSDS headers currently installed on their 16v 928 and would like a "free" upgrade. Bring us your car and we will do a baseline dyno pull on it. Then we will swap out your Gen 1 headers for the new Gen 2 headers with merged collectors, and dyno it again.
Here are your costs: The headers will be no cost to you. You will not have to pay for the dyno time either. You will be charged 50% shop labor rate to swap the headers.
Let me know!
PS: same deal is available for somebody with a 32v 928 and a set of Gen 1 MSDS headers installed....
#20
If no one jumps at the offer, we can use my track car but I'm not driving my 79 to Horicon. A lot easier to just ship the headers up here.
Here is the before:
https://rennlist.com/forums/928-foru...t-exhaust.html
This is assuming the new headers will bolt up to my exhaust.
Here is the before:
https://rennlist.com/forums/928-foru...t-exhaust.html
This is assuming the new headers will bolt up to my exhaust.
#23
is there an other reason why they cant angle around the lower bell housing like the S4 style?
#25
all these things are in the design parameters. equal length primaries or close to; clutch service (at least not worse than present)
I think what makes them angle in so aggressively is the attempt to meet up at the stock exhaust before the catalytic converter.
I think what makes them angle in so aggressively is the attempt to meet up at the stock exhaust before the catalytic converter.
#26
Roughly what kind of HP increase could one expect to see with these over stock headers on an 87?
The car is supercharged if that makes a difference.
The car is supercharged if that makes a difference.
#28
About a year ago, there was a thread on here about some China rip-off MSDS headers on eBay... and you may recall, toward the end of that thread the conversation had turned to merged collector headers