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  • #61
    I just want to get one thing clarified; The ADU pulley VS AAN/ABY. The ADU; relation between the timing mark on the cam sprocket and the "key" is 10 degrees (retarded) compared to the AAN/ABY? This means that if you run an ADU cam pulley both cams will be 10 degrees retarded ?
    Now you see me, now you don`t

    80quattro.com

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    • #62
      I am surprised to see the 7A inlet/AAN EX combo is so much better than the ADU package. I would have expected the higher lift of the ADU ex cam to give additional headroom top-end.

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      • #63
        Btw. I see you have used a total engine volume 2311 ccm. Did you use a 7A block as reference?

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        • #64
          Originally posted by RWD19T View Post
          zip file didn't attach on last post?
          Thanks!

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          • #65
            I just used the 5cyl option already in the program rather than programming it in. As it was the same stroke the difference in bore size is neglible in the grand scheme of the results.

            Remember the lift is not that significant in the grand scheme of things either as the higher the lift of the cam the less time it spends in the middle lift range where these heads in standard form flow best if you look at the real life flow files attached. Nor do the heads flow well at high lift in standard form it's not until the valve and seat work that was carried out on my stg1 head that you start to get the real benefits of the high lift cams. One of the reasons that if you where to fit the ADU pulley to the standard AAN/ABY camset you get the same sort of power results. Which is ironically an easier and cheaper mod than swapping the cams. (He stupidly says devalueing the resale value of his RS2 cams after testing )

            One other thing to note is that power is made from better cylinder filling rather than getting rid of it. Hence the intake cam swaps have the most significant hp increases. Which is where the simulation is partially inacurate as it doesn't keep in account that improved exh flow spools the turbo faster subsequently providing more boost earlier on in the rev range, it also ensures a cleaner air mixture due to better scavenging for a better burn. Both of which accentuate the low down torque curve as I have found in my real life testing of the chip sets I'm going through at the moment.

            For this reason I would like to get hold of a set of NM cams to do a final test once finished with the chipsets. Obviously the results on my car will only be reflective of a stg1 head not a standard as the flow curves will change the behavioural characteristics of the engine in respect of the cams but it will be interesting to compare to the curves of the stg1 simulations as it will then give an indication of how accurate the curves are for the standard head simulation.
            UrS6 Stroker + HTA3586 =

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            • #66
              Good luck getting hold of a set of NM cams!

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              • #67
                ^^^ I can only imagine However I now no longer need to.....







                .....as in my search for more info trying to find some NM cams I now have some more info on the 7A exhaust profile. Originally it didn't seem right to me as it was the same duration and valve event timing as that of the AAN only higher lift which seemed strange for NA application. So I've ammended this along with some of the details shown below in the original data list, the changes highlighted in red to bring it in line with the details used in the simulations and to make the valve timing correlate to the durations.


                AAN, ABY, 3B___ Opens 3° BTDC, closes 25° ABDC, duration 202°, lift 8,3mm

                ADU__________ Opens 13° BTDC, closes 35° ABDC, duration 202°, lift 8,3mm

                NM __________ Opens 0° ATDC, closes 32° ABDC, duration 212°, lift 9,6mm

                7A___________ Opens 6° BTDC, closes 38° ABDC, duration 212°, lift 9,6mm

                Exhaust

                AAN, ABY, 3B___ Opens 42° BBDC, closes 9° BTDC, duration 213°, lift 8,6mm

                ADU__________ Opens 24° BBDC, closes 1° ATDC, duration 205°, lift 9,5mm

                NM __________ Opens 35° BBDC, closes 3° BTDC, duration 212°, lift 9,6mm

                7A___________ Opens 42° BBDC, closes 3° BTDC, duration 219°, lift 10,5mm

                This very minor change on the duration of the 7A cam now makes for a much better lobe seperation angle (higher which is better for FI) and innevitably has created the best mid to top end power curve yet

                See below the simulation of 7A exh as intake and NM exh as exhaust vs using 2 7A exhaust cams.



                Now this got me thinking so I ran the iterator again (cam profile simulator) this time I specified maximum torque under the curve from 2000-7000rpm. This is where the real revelation came; the intake cam specification recommended for the most area under the torque curve is identical to the ADU intake spec. Whereas the closest exhaust profile is that of the 7A. So I ran the ADU with 7A exh cam again and compared it first to the AAN/ABY retarded 3 degrees.



                As you can see although there is a small torque sacrifice low down the mid to top end gains are significant.

                Then compared it to the twin 7A exh configuration. Which although it runs out of steam for the upper end of the rev range the ADU-7A combo makes for much better low to midrange driving.



                Well this got me thinking a bit more as the ADU engine is a high boost item from standard so I decided to do a final test and upped the boost pressure and this is where the most interesting results came through. Here's all 3 of the above back to back at the boost level expected on a chipped ECU.




                This is where it looks like the best all rounder for driveability becomes the ADU int with 7A exh. With barely a drop in low down torque compared to the AAN running 3 degrees retarded. Still pulling a healthy mid to top end for those overtaking manouvres. So now how to figure out to set up that combination on an engine without valve to piston clearance issues or upsetting the exh timing by using the ADU pulley.
                UrS6 Stroker + HTA3586 =

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                • #68
                  Originally posted by RWD19T View Post
                  , the changes highlighted in red to bring it in line with the details used in the simulations and to make the valve timing correlate to the durations.


                  AAN, ABY, 3B___ Opens 3° BTDC, closes 25° ABDC, duration 202°, lift 8,3mm

                  ADU__________ Opens 13° BTDC, closes 35° ABDC, duration 202°, lift 8,3mm

                  NM __________ Opens 0° ATDC, closes 32° ABDC, duration 212°, lift 9,6mm

                  7A___________ Opens 6° BTDC, closes 38° ABDC, duration 212°, lift 9,6mm

                  Exhaust

                  AAN, ABY, 3B___ Opens 42° BBDC, closes 9° BTDC, duration 213°, lift 8,6mm

                  ADU__________ Opens 24° BBDC, closes 1° ATDC, duration 205°, lift 9,5mm

                  NM __________ Opens 35° BBDC, closes 3° BTDC, duration 212°, lift 9,6mm

                  7A___________ Opens 42° BBDC, closes 3° BTDC, duration 219°, lift 10,5mm

                  This very minor change on the duration of the 7A cam now makes for a much better lobe seperation angle (higher which is better for FI) and innevitably has created the best mid to top end power curve yet
                  What do you base these corrections on? They are wrong
                  I've measured several sets of 7A cams and intake is 6 ATDC ant not BTDC.
                  If your numbers where correct the 3B,ABY inlet would be 208° and ADU 228°. A bit of a problem since it's the same cam just timed 10° different

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                  • #69
                    My values were taken from Audi_CQ who measured the cams so why the correction?

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                    • #70
                      Originally posted by Audi_CQ View Post
                      What do you base these corrections on? They are wrong
                      I've measured several sets of 7A cams and intake is 6 ATDC ant not BTDC.
                      If your numbers where correct the 3B,ABY inlet would be 208° and ADU 228°. A bit of a problem since it's the same cam just timed 10° different
                      I used a cam design simulator where you input valve event values and it calculates duration and lobe seperation for you. I've attached a jpg of the input values for the 3B/ABY inlet and the ADU and the values the simulator comes up with.



                      I just realised where I gone wrong as I typed this, it looks like the program is taking BTDC as a standard and using the -ve symbol as interpretation of ATDC. I made the assumption that the TDC was my zero point and therefore the -ve meant Before and +ve After. Should have drawn it out by hand first. Or read the instruction manual to the software

                      So it appears that the only change is the EVC on the 7A then?
                      UrS6 Stroker + HTA3586 =

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                      • #71
                        Where does that leave the graphs posted previously then? Prob. best to remove any calculated on the wrong data to avoid confusion. I'll be interested to see the revised 7A in AAN ex results...

                        Cheers for all the hard work. Makes for an very interesting thread!
                        Cheers'en, AndyC
                        1994 ABY Coupe - Projekt Alpinweiss

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                        • #72
                          Originally posted by Andy_Casey View Post
                          Where does that leave the graphs posted previously then? Prob. best to remove any calculated on the wrong data to avoid confusion. I'll be interested to see the revised 7A in AAN ex results...

                          Cheers for all the hard work. Makes for an very interesting thread!

                          All the graphs where based on ATDC figures as originally posted up. The mistake lay with myself in misinterpretin the input of the data. Basically when I first added positive numbers the durations where wrong so I input minus figures to ensure correct durations. Subsequently I then misinterpreted the minus symbol to mean BTDC whereas it actually did correctly represent ATDC as the programs default was BTDC so by inputting a -ve into the value box it changed it to ATDC for the correct durations.

                          Subsequently the only change made is that of the closing of the exhaust cam of the 7A which does not effect your cam combo. Likewise anything it does effect is so minimal you barely notice a flicker in the power curves other than a tiny drop in low end tq and a small rise in top end hp over 6500rpm. So no real need to repost any results. The only major one of interest is the dual 7A exh setup so I'll be looking at getting hold of a 2nd 7A exh cam in order to test it.

                          I'd also like to get hold of an ADU cam pulley as I want to work out exactly how the valve event timings are effected by it in a mechanical way if at all as I need to see how the 7A cam can be implemented into the ADU equation. As it's my understanding that the timing reference window is to indicate TDC so it as been mounted 10degrees of in order to maintain perfect TDC on the timing window whilst mechanically retarding the cams. As a simulated timing retard in the ignition timing would not have the same gains as to physically rotating the cams if anything it would make a loss. So anyone that may have one they wish to either donate to research or wish to sell please pm me on the ADU pulley front.
                          UrS6 Stroker + HTA3586 =

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                          • #73
                            Originally posted by RWD19T View Post
                            All the graphs where based on ATDC figures as originally posted up. The mistake lay with myself in misinterpretin the input of the data. Basically when I first added positive numbers the durations where wrong so I input minus figures to ensure correct durations. Subsequently I then misinterpreted the minus symbol to mean BTDC whereas it actually did correctly represent ATDC as the programs default was BTDC so by inputting a -ve into the value box it changed it to ATDC for the correct durations.

                            Subsequently the only change made is that of the closing of the exhaust cam of the 7A which does not effect your cam combo. Likewise anything it does effect is so minimal you barely notice a flicker in the power curves other than a tiny drop in low end tq and a small rise in top end hp over 6500rpm. So no real need to repost any results. The only major one of interest is the dual 7A exh setup so I'll be looking at getting hold of a 2nd 7A exh cam in order to test it.

                            I'd also like to get hold of an ADU cam pulley as I want to work out exactly how the valve event timings are effected by it in a mechanical way if at all as I need to see how the 7A cam can be implemented into the ADU equation. As it's my understanding that the timing reference window is to indicate TDC so it as been mounted 10degrees of in order to maintain perfect TDC on the timing window whilst mechanically retarding the cams. As a simulated timing retard in the ignition timing would not have the same gains as to physically rotating the cams if anything it would make a loss. So anyone that may have one they wish to either donate to research or wish to sell please pm me on the ADU pulley front.
                            I just lost you, with all these theory talks. Just put in some cams and report back to us

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                            • #74
                              ^^^ lol most of the cam profiles that are important and have positive results have been covered. What I'll do sometime this week is post up the best all rounder best hp best low down torque in one post for ease of overview. i just need to confirm one thing first with the ADU pulley set up.

                              I know that the waterpump and belt have different amount of teeth. I know the timing window is supposedly in a different place I know according to RS2 owners when you time it up the mark on the cam pulley is not supposed to line up a 100%. I wish to confirm that the combination of these factors mean that the intake and exhaust are physically shifted by 10 degrees because if that is the case then there is an even cheaper alternative to the ADU cam setup than using the 7A intake, which will ultimatelly be the best all rounder. However until I can get hold of the pulley though it is all theory and I wont post the info incase it is wrong.
                              UrS6 Stroker + HTA3586 =

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                              • #75
                                Great, thanks for clearing that up.
                                Cheers'en, AndyC
                                1994 ABY Coupe - Projekt Alpinweiss

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