HIGHWAYMAN: Bringing the Devore 928 back from the dead
02-09-2017, 08:00 PM
#511
Banned
Thread Starter
Took a minute to check in during this 3x as long garage remodel...
Ptuomov,
We are in uncharted territory with this intake. Carl and I knew full well that extrude hone had been tried and failed, but we did not know if the extrude hone coupled with a larger intake shoe had been tried. At my request, I offered to pay for some of the hard costs of the R&D, and Carl offered to throw in his time and labor to see if we can make anything of it. if it doesn't work, it doesn't work.
It's basically a "no stone unturned" stock intake manifold experiment.
Ptuomov,
We are in uncharted territory with this intake. Carl and I knew full well that extrude hone had been tried and failed, but we did not know if the extrude hone coupled with a larger intake shoe had been tried. At my request, I offered to pay for some of the hard costs of the R&D, and Carl offered to throw in his time and labor to see if we can make anything of it. if it doesn't work, it doesn't work.
It's basically a "no stone unturned" stock intake manifold experiment.
02-10-2017, 08:26 AM
#512
Nordschleife Master
Ptuomov,
We are in uncharted territory with this intake. Carl and I knew full well that extrude hone had been tried and failed, but we did not know if the extrude hone coupled with a larger intake shoe had been tried. At my request, I offered to pay for some of the hard costs of the R&D, and Carl offered to throw in his time and labor to see if we can make anything of it. if it doesn't work, it doesn't work.
It's basically a "no stone unturned" stock intake manifold experiment.
We are in uncharted territory with this intake. Carl and I knew full well that extrude hone had been tried and failed, but we did not know if the extrude hone coupled with a larger intake shoe had been tried. At my request, I offered to pay for some of the hard costs of the R&D, and Carl offered to throw in his time and labor to see if we can make anything of it. if it doesn't work, it doesn't work.
It's basically a "no stone unturned" stock intake manifold experiment.
02-10-2017, 12:41 PM
#513
Banned
Thread Starter
We're going to let everyone know the results regardless. There is no sort of competition on here, and there is little point in not telling people the results.
If it doesn't work, you'll hear it from me and Carl first.
If it doesn't work, you'll hear it from me and Carl first.
02-10-2017, 01:36 PM
#514
Developer
Adam,
Your merged-collector headers just came back from Jet-Hot. Here are some pics. They are being re-boxed and should leave here Monday morning for you.
On my 928, the trick setup is to bolt the right header to the engine while it hangs from the engine hoist. (We also like to install the clutch and bell housing on the motor at this time). Lay the left header down in the engine bay and hold it from falling with a zip-tie. Then put in the motor. The right header is already bolted up, and when you cut the zip tie the left header is already in place and ready for fasteners. Works slick.
Your merged-collector headers just came back from Jet-Hot. Here are some pics. They are being re-boxed and should leave here Monday morning for you.
On my 928, the trick setup is to bolt the right header to the engine while it hangs from the engine hoist. (We also like to install the clutch and bell housing on the motor at this time). Lay the left header down in the engine bay and hold it from falling with a zip-tie. Then put in the motor. The right header is already bolted up, and when you cut the zip tie the left header is already in place and ready for fasteners. Works slick.
02-10-2017, 07:24 PM
#516
Archive Gatekeeper
Rennlist Member
Rennlist Member
Not sure what the statute of limitations on copyright is, but I came across a copy of the Highwayman article from Excellence's August 1990 issue and scanned and OCR'ed it. Here's a link to the PDF, I can take it down if anyone objects.
https://webfiles.uci.edu/redwards/pu...e%202-2-17.pdf
https://webfiles.uci.edu/redwards/pu...e%202-2-17.pdf
02-10-2017, 09:02 PM
#517
Banned
Thread Starter
Rob,
Thanks for posting. Obviously I don't own the copyright, but it IS my car, so I therefore bless the posting of it!
As soon as I bought the car, I ordered the back issue of the article, so I have the hard copy. Kind of cool. The Devore car was much modified from when that article was printed, but still a cool glimpse into the mindset of the man.
Thanks for posting. Obviously I don't own the copyright, but it IS my car, so I therefore bless the posting of it!
As soon as I bought the car, I ordered the back issue of the article, so I have the hard copy. Kind of cool. The Devore car was much modified from when that article was printed, but still a cool glimpse into the mindset of the man.
02-13-2017, 12:26 PM
#518
Developer
Here is what I meant about the headers. We happened to be putting my motor in my own car Saturday and I grabbed these pics for you.
Left header laying down, zip-tied to hold it still. Right header bolted up to the motor.
We also like the solid mounts bolted to the cross-member (as shown). Then we can just install the 2 bolts per side up through them and into the block and we're done.
Left header laying down, zip-tied to hold it still. Right header bolted up to the motor.
We also like the solid mounts bolted to the cross-member (as shown). Then we can just install the 2 bolts per side up through them and into the block and we're done.
02-14-2017, 01:03 PM
#521
Developer
Head porting results
Adam,
Your heads are finished and they turned out very well. I had the stock heads flow-benched before we began porting work on them so we would have an accurate baseline. Note that your intake valve seats had been enlarged to hold a 39mm (stock is 37mm) intake valve prior to the baseline test, so this flow-chart comparison is an accurate representation of the porting work only.
We were able to get very good flow numbers out of them, rivaling and even beating the flow in places compared to my CNC-milled boosted heads. We did not lower the floor as far as last time, which helps avoid unnecessary turbulence and also keeps air flow velocities up, which will help your naturally-aspirated motor a lot.
Your heads are finished and they turned out very well. I had the stock heads flow-benched before we began porting work on them so we would have an accurate baseline. Note that your intake valve seats had been enlarged to hold a 39mm (stock is 37mm) intake valve prior to the baseline test, so this flow-chart comparison is an accurate representation of the porting work only.
We were able to get very good flow numbers out of them, rivaling and even beating the flow in places compared to my CNC-milled boosted heads. We did not lower the floor as far as last time, which helps avoid unnecessary turbulence and also keeps air flow velocities up, which will help your naturally-aspirated motor a lot.
02-16-2017, 09:22 AM
#523
Nordschleife Master
I had the stock heads flow-benched before we began porting work on them so we would have an accurate baseline. Note that your intake valve seats had been enlarged to hold a 39mm (stock is 37mm) intake valve prior to the baseline test, so this flow-chart comparison is an accurate representation of the porting work only.
What exactly is "stock" here?
(1) All stock
(2) Larger valve seat inserts but stock 37mm valves
(3) Larger valve seat inserts and 39mm valves
(4) Something else?
02-16-2017, 12:09 PM
#524
Developer
The "Stock" measurements above are of a stock head after the intake valves had been replaced with 39mm valves and seats. So they are not "dead-stock", which is why i mentioned it. Even the baseline flow chart would already show these improvements compared to a dead-stock head with 37mm intake valves.
If you want to know the gain in CFM from moving from the 37mm intake valve and seat to the 39mm valve and seat; I have flow charts from another test/machine that show it was worth a gain of 56.66 CFM at a valve lift of .450". In other words, the air flow of a dead-stock 32v Type 3R head at .450" valve lift was 267.30 CFM.
It doesn't corroborate perfectly to the chart above, because different flow-meters were used by different operators. But It does provide some idea as to the before-and-after gain of going to the larger valve.
If you want to know the gain in CFM from moving from the 37mm intake valve and seat to the 39mm valve and seat; I have flow charts from another test/machine that show it was worth a gain of 56.66 CFM at a valve lift of .450". In other words, the air flow of a dead-stock 32v Type 3R head at .450" valve lift was 267.30 CFM.
It doesn't corroborate perfectly to the chart above, because different flow-meters were used by different operators. But It does provide some idea as to the before-and-after gain of going to the larger valve.
02-16-2017, 12:30 PM
#525
Nordschleife Master
The "Stock" measurements above are of a stock head after the intake valves had been replaced with 39mm valves and seats. So they are not "dead-stock", which is why i mentioned it. Even the baseline flow chart would already show these improvements compared to a dead-stock head with 37mm intake valves.
If you want to know the gain in CFM from moving from the 37mm intake valve and seat to the 39mm valve and seat; I have flow charts from another test/machine that show it was worth a gain of 56.66 CFM at a valve lift of .450". In other words, the air flow of a dead-stock 32v Type 3R head at .450" was 267.30 CFM.
It doesn't corroborate perfectly to the chart above, because different flow-meters were used by different operators. But It does provide some idea as to the before-and-after gain of going to the larger valve.
If you want to know the gain in CFM from moving from the 37mm intake valve and seat to the 39mm valve and seat; I have flow charts from another test/machine that show it was worth a gain of 56.66 CFM at a valve lift of .450". In other words, the air flow of a dead-stock 32v Type 3R head at .450" was 267.30 CFM.
It doesn't corroborate perfectly to the chart above, because different flow-meters were used by different operators. But It does provide some idea as to the before-and-after gain of going to the larger valve.
Just to confirm in detail about the "base": The "base" in these tests has 39mm valves and valve seat inserts that fit 39mm valves. Those base 39mm valve seat inserts have a throat diameter that is larger than the stock S4 valve seat's throat diameter. The casting was not modified at this point, other than to fit the larger valve seat insert.
And to confirm about the modified: The modified was then ported by possibly somewhat expanding the new valve seat insert throat, but mainly by cutting material from the casting to match the new valve seat insert throat. In other words, the aluminum casting lip was removed. Eyeballing the flow bench results, I'd wild a$$ guesstimate that the aluminum throat diameter went from about 31mm to about 33.5mm in the process? Then there were some additional "normal" porting modifications done to improve flow.
What's your test pressure, out of curiosity? Interested in both the actual test pressure and the pressure number to which the raw measures were corrected to for reporting.