Again thanks for the advice all jumped and explained it really helped a lot. I would not have done this in just over a year with FABO great group of folks appreciate it. Been following builds here since 2010.
Here’s the thing, there are several companies that offer a 1.6 roller rocker but they do not all exact lift the valve a true 1.6 mathematically. Or in actuality. Is the differences in the contact point of the roller tip the push rod contact point and the frog buckram point and the differences between them, additionally, pushrod length also has a play in this. Double check to see what your actual lift is.They are true 1.6 ratio roller rockers red and blue in picture. Stock are actually below 1.5. checking cam spec valve lift I'm now 526 intake and 540 exhaust. This cam is @107 rather than 110 so has overlap. For sure need to go to 3.73 rear gear. I fixed the tachometer tonight pulled out of loom and wrapped in foil tape. Also put that inside a 1/4 vacuum hose ran through one of the plugs it used for firewall insulation. Then checked no RFI issues tach is steady at idle. Speedometer same issue fixed tomorrow. Ran it up first gear 4500 holy cow and into 2nd before I chickened out. She is ready to go for sure. Just needs miles like you said rumble fish. Temps still right at 190 or lower very pleased with AC I needed it down low Oklahoma is HOT.
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According to build sheet and what I and builder did it is as specified a 1.6 ratio. The stock push rods were short so they were changed out and measured for correct length and what we wanted to accomplish. Would not have used them anyway as pretty old as they were old tired looking rocker assembly.Here’s the thing, there are several companies that offer a 1.6 roller rocker but they do not all exact lift the valve a true 1.6 mathematically. Or in actuality. Is the differences in the contact point of the roller tip the push rod contact point and the frog buckram point and the differences between them, additionally, pushrod length also has a play in this. Double check to see what your actual lift is.
What is the cam card saying for it’s lift?According to build sheet and what I and builder did it is as specified a 1.6 ratio.
Of course, there’s no other way. ;)The stock push rods were short so they were changed out and measured for correct length and what we wanted to accomplish.
As in the old/OE rockers?Would not have used them anyway as pretty old as they were old tired looking rocker assembly.
Large thumper cam and things have been changed were going to manual choke that's solved and the why. Getting rid of the vacuum advance on the distributor got a plate to install. It's driving great it really does not need a choke but since it's there manual if I need it just in case cable will be there. I changed the power valve 3.5 rear jets to 84. A/F sensor reads right around 11 to 11.5 idle but will adjust the idle metering screws out a smidge now. Driving A/F sensor is showing 11.5 to 13.5 it's a good average of 12.5. Power valve was 6.5 not bad but the 3.5 is a huge success. Matches the vacuum now of cam. Timing I'm at 18 degrees and total timing at 35. It's very snappy now and driving great best I have tuned it since I got her up and running. We're I to purchase carburetor again I would have gone non choke 750/850. Distributor would have had no vacuum advance from the start. Lessons learned and I can argue why you don't need those things on a hopped up strip street car driven on cruise in and for fun.how much initial timing do you have on the engine?
I know you have a thumpr cam is it the small, mid or large one. If someone told you you would get 13in of vacuum with the mid or large one, yeah not gonna happen at a typical idle level. The large one is 240+ at .050, not "idle" or vacuum friendly.
Have fun with it. Good to read it is broken in and running strong.
Wrote a big book below with comments on the ZF 8HP70 below. Launcher launches hook ups all of the above in the why. Sport mode/track mode and highway economy driving mileage wow on a built motor all true! Oh yeah manual mode hahaha on built engine in light A body. Lots of fun donuts and track the car check and check all day. The car is amazing I would never touch a 3 speed 904 or 727. ZF is plentiful reliable takes big power. Is there work to be done yes see my transmission thread it's still well worth the work as the reward is amazing.Appreciate this thread so much. You're at the finish line and i'm in your draft. Sucks when a machine shop takes their merry lovin time so I felt that when you got your block back. I just got mine after 11weeks of waiting for overbore, crank R&R and cam bearings done, and still have to build the bottom end. Expensive hobby but can't wait to fire up and get some of the same reward!
Also, what sold you on going to a ZF 8hp70 transmission next? curious as my 727 is a big question mark for me still.
I have no dog in this hunt. But I will mention the westech dyno seems to be a little on the happy side compared to others.See engine labs dyno build 360, I do plan to do some head work and I'm bumping compression up as well 10.2 to 1 should be right on the edge of 400 with better compression which they left bottom end stock pistons. Modifying And Testing A Dodge 360-Cube LA Small-Block On The Dyno
400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dynoI have no dog in this hunt. But I will mention the westech dyno seems to be a little on the happy side compared to others.
For instance a stock rebuilt high compression 340 with headers and the comp 268 cam supposedly made 400 hp as well.
That said what you are putting together sounds like a great low buck street combo no matter what the actual horse power level winds up at.
Has it been down the track? Sounds like a solid combo.400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dyno
Cool build. I like them all and appreciate the hard work we all put in to our rides.400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dyno
just once , not a good time it was hot with a full tank of gas 13.6 @108Has it been down the track? Sounds like a solid combo.
Agreed I know it's not stock but my car is resto mod.that 8hp70 transmission is the best choice , wish I had enough time left to put one in my car ,It can't be beat for mpg or 1/4 mile times
400 hp is possible my 340 dynod at 450hp with a decent cam 573 lift 1.6 rockers and trick flow heads . Don't think it was a happy dyno
I was slow off the line smoked through 1st and almost lost it hitting 2nd , with a better driver it could do much better108 mph is a 12.30 with good short times. Moves pretty good according to the MPH!
with that 8 speed and 400+ hp you better have good brakes , and locking up the wheels at 120mph is not what you want . Brakes should be number 1 on your to do listAgreed I know it's not stock but my car is resto mod.
My cam is well past the 268 now with 1.6 roller rockers installed 541 Intake and 528 exhaust. I weigh less than Russel Drake's truck from Sound German Automotive and he runs an 11 same transmission and horsepower nearly the same I'm told and out weighs me close to 900 pounds. I expect an 11 goofing around on phone timers Im seeing numbers that indicate I should be there. I'm a little concerned about going to track.
SAFETY. I need to handle the brakes and get a vacuum system installed to pump up the booster. It's a little low they work ok but I need to be able to be able to lock the car up and takes a little to much effort. With the 8 speed this car is over 120 mph very quickly it tracks great now and such stopping is my big worry. I'm not dying first trip to track lol! I do t expect to lock them but I do expect lot more brakes than I got now. They are brand new and they work pretty good in town but way to soft that's the low vacuum at work.
Exactlywith that 8 speed and 400+ hp you better have good brakes , and locking up the wheels at 120mph is not what you want . Brakes should be number 1 on your to do list