Your donations help keep this valuable resource free and growing. Thank you.
|
9.70 at 135 – Edelbrock Heads, E85 |
Post Reply | Page <1234 5> |
Author | ||||||||||||||||||||||||
ramblermoosecocka
AMC Fan Joined: Jan/14/2015 Location: Michigan Status: Offline Points: 10 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Thanks. The cam is a custom Harold Brookshire (Ultradyne, etc.) 28 deg piece, 259/267 at .050, cut on a 106 LSA, installed at 101. Tight lash; .650 net lift. Harold was adamant that the combo would ET best with 106/101, but I have not confirmed by trying anything else. I have had experience with 3 engines that use this lobe series, and each ran faster than expected (only one install was cam only, however - the ET dropped 3 tenths in the 1/4 over the same combo with a Comp .420 cam in a consistent car. Same LSA, same lift.). Also, these lobes appear to be relatively easy on parts.
|
||||||||||||||||||||||||
SC397
AMC Addicted Joined: Apr/30/2009 Location: Michigan Status: Offline Points: 5428 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Page 3 shows the Dyno Session (72. BradmobileII427)
http://rebsamcandjeep.proboards.com/thread/144/dyno-time?page=3 I will try to re-post the pictures. |
||||||||||||||||||||||||
SC397
AMC Addicted Joined: Apr/30/2009 Location: Michigan Status: Offline Points: 5428 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Page 14-15 tells a little bit about the engine build. His is listed as 72. BradmobileII427 on this forum.
http://rebsamcandjeep.proboards.com/thread/11/amc-engine-builds?page=14 The man the myth the legend.. LOL! Bradfarmguy by Rick Jones, on Flickr |
||||||||||||||||||||||||
ramblermoosecocka
AMC Fan Joined: Jan/14/2015 Location: Michigan Status: Offline Points: 10 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Here is the cylinder head flow data, from a conservative local bench that a number of us in SE MI have used. MCSA of the intake port is 2.52 sq-in, so it is relatively large and slow (average velocity at .600 is 275 fps). Maybe this is what E85 wants. There is more liquid taking up space and adding charge momentum in the port, so big and slow may make it easier to make the turn to the valve. This is all a guess however. The Edelbrock's have a more modern chamber shape, and there may be other subtle port shape improvements over stock.
BTW, 6.61 sec in the 1/8 converts to 10.40's in the 1/4. At 3250#, a fast car by any standard.
|
||||||||||||||||||||||||
pfordamx
AMC Apprentice Joined: Sep/13/2010 Location: OKC Status: Offline Points: 173 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
i thought harold had passed and i noticed bullet shows to now own ultradyne do you happen to know the lobe # used on this cam?
|
||||||||||||||||||||||||
ramblermoosecocka
AMC Fan Joined: Jan/14/2015 Location: Michigan Status: Offline Points: 10 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Regarding the camshaft duration, I have shifted as high as 7100, and the engine does not nose over. But there is no ET advantage to shifting there over the 67-6800 that I settled on, where it seems to be pulling a little harder. An educated guess is that peak HP is around 6600, based on feel and on comparison to the cam the engine was dyno'd with. RPM range seems to be a reasonable match to the gear ratio and torque converter, etc.
|
||||||||||||||||||||||||
ramblermoosecocka
AMC Fan Joined: Jan/14/2015 Location: Michigan Status: Offline Points: 10 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Yes, Harold is deceased, unfortunately. Generous, talented, and hard-working man. But before he became that way, he spec'd the cam I used. He sent the CNC data to Steve Slavik at Lunati for grinding. I have the lobe numbers at home, will post them tomorrow. Steve worked with Harold at Ultradyne for many years. He should be able to set you up. The duration, as well as the lift, of the lobes I used is much smaller than the one in your motor, as you probably noticed. There are many others in the series to choose from.
|
||||||||||||||||||||||||
Ken_Parkman
AMC Addicted Joined: Jun/04/2009 Location: Ontario Status: Offline Points: 1815 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
BTW the 2.52 csa shows a peak of about 6800 on the calc I use. I'm of the opinion too high a velocity is a bad thing, especially on a stockish port height like the Edelbrock. Just too hard to keep the flow attached on the ssr. Clearly it works well in your combo!
|
||||||||||||||||||||||||
amcenthusiast
AMC Addicted Joined: Jul/02/2012 Location: SW Atlanta GA Status: Offline Points: 1778 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Congratulations on the great running well sorted out engine, proving again there is more potential in AM V8s than most mainstream auto enthusiasts are willing to admit.
One more example of an intelligent AM V8 engine builder who's used my "AMC V8 Oil System Modifications" information successfully. *notice the rods don't have the stock oil spurt feature either, which is key to building a successful '56-'67 AM RV8 race engine also. Edited by amcenthusiast - Oct/26/2017 at 8:14pm |
||||||||||||||||||||||||
443 XRV8 Gremlin YouTube video: https://www.youtube.com/watch?reload=9&v=2DmFOKRuzUc
XRV8 Race Parts website: http://amcramblermarlin.1colony.com/ |
||||||||||||||||||||||||
SKeown
AMC Addicted Joined: Jul/30/2009 Location: Texas Status: Offline Points: 3085 |
Post Options
Thanks(0)
|
|||||||||||||||||||||||
Those mods are? SKeown
|
||||||||||||||||||||||||
Post Reply | Page <1234 5> |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |