Rat Patrol
Well-Known Member
Mocars - put it over a weigh bridge st the local tip - they wont charge u.
Great stats! I would be interested in what lifters/springs/rockers you are using to get this kind of RPM. Also what ignition are you using?67 Cuda Fastback 3350# 5.7 stock stroke .020 over
12.5:1 6.1 heads ported 2.10 intake valves. .569 .593 cam
6300 converter 904 Trans. 5.14 gear 30x9 Mickey Thompsons
1.31 sixty 6.28 1/8 9.99 at 130 mph. Drag Pak combo NHRA legal.
Shift at 8000 cross at 8300.
Eddie
Good to know. I have 2 years on my motor that has a stock valvetrain. I shift at 6500 and limiter is set at 7200, but after 2 years it's probably about time for new springs and I'm wondering if I can increase the RPM safely with just new springs and rockers.Lifters are stock non-mds blocked to make them solid. Harland Sharp adjustable rockers.
Valves, springs, retainers + keepers are all Manley-- Don't know the part #'s or specs. David Barton at Ray Barton Racing Engines set everything up for me. He has countless hours of R+D in these things and can make them flat out fly with very basic set-ups. He has run the same rpm range with stock rockers. The combo is fuel injected, and I have the AEM infinity system which drives the ignition and the fuel injectors. Stock coils.
Eddie
400 lbs. wow! Thanks for the info!!I know that you don't need a lot of spring pressure to make these things rev. I tried building this engine with eagle heads and a carb at first, but I was using the same theory as a small block when setting up the springs. I was setting them up with close to 700 lbs of open pressure-- needless to say I was breaking rocker arms like twigs. After breaking the rocker stands on one of the heads I took my 6.1 heads to Barton. My jaw hit the floor when he told me they were twisting them to 8000 with around 400 pounds of open pressure. I would say if you went with the Manley springs- you should be safe twisting it a little higher. Keep in mind that you want to keep everything as light as possible ( titanium retainers & keepers).
Well, it was until the ring and pinion let go about 3 weeks agoNo problem! Hope to visit your state someday--- it's on my bucket list.
Everyone I know that's visited Texas has loved it -- two of my friends actually liked it so much they moved there! BTW- Your combo seems to be running pretty darn good!
I wonder how much open pressure the stock springs are?My jaw hit the floor when he told me they were twisting them to 8000 with around 400 pounds of open pressure.