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I just had a motor built and now the builder has bailed the problem is to get it to start the timing has to be at 4 degrees retarded the motor is a 351/393 with 030 over bore and at 10 to 1 compression 4v quench heads stock intake and exhaust stock dist with pertronics I checked TDC and it is right on and the cam lobe center line is what the cam card says i even put on a high torque starter to help with the hard starting with the timing anywhere close to being on not much help so im alittle lost any help would be great
CrazySCo_hmmthink
Sorry I wish I could help you on this one. It sucks the builder bailed. Loser

Hard starting is usually caused by to big of cam.
This is what I learned from building a big motor without thinking about the parts that we going into the build.

Hopefully someone here knows this answer for you!
OK lets check a few thoughts here. Are we sure of the compression 10 to 1 should give you roughly 150 psi on the compression guage. Thats 10 times the atmospheric pressure of 14.7 rounded to 15 or approx 150 psi. Now how are you checking the timming? If you are using a timing light is it the adjustable style? If so did you set it correctly? How about the timming cover is it correct for the engine as some pointers were different then others. Next the balancer. Is it the original stock? If so is the rubber swelled and possibly the outer ring has slipped throwing all settings off? Then there is the key for the balancer is it in place and not sheared off, which would throw everything off? Check out these ideas and let me know what you find! Depending on what you find there may be a few more things to check.
JTS 71 Mach1
A compression test i have not done the timing pointer was on the engine before and it had not been touched pryer the timing light is nonadjustable and TDC was found with a piston stop and coinsides with the markings on the dampener and the dampener is a new one
(01-16-2011, 12:09 PM)Mach1LloydAb Wrote: [ -> ]I just had a motor built and now the builder has bailed the problem is to get it to start the timing has to be at 4 degrees retarded the motor is a 351/393 with 030 over bore and at 10 to 1 compression 4v quench heads stock intake and exhaust stock dist with pertronics I checked TDC and it is right on and the cam lobe center line is what the cam card says i even put on a high torque starter to help with the hard starting with the timing anywhere close to being on not much help so im alittle lost any help would be great
CrazySCo_hmmthink

Found this today still looking for something to back it up.




I have a '72 351C 2V I am putting in a 56 ford sedan. After some research on the motor specs, I saw the big HP drop on these motors between '71 and '72. One of the changes the factory made was retarding the cam timing 4 deg.
(01-17-2011, 01:51 AM)1969jimmach Wrote: [ -> ]
(01-16-2011, 12:09 PM)Mach1LloydAb Wrote: [ -> ]I just had a motor built and now the builder has bailed the problem is to get it to start the timing has to be at 4 degrees retarded the motor is a 351/393 with 030 over bore and at 10 to 1 compression 4v quench heads stock intake and exhaust stock dist with pertronics I checked TDC and it is right on and the cam lobe center line is what the cam card says i even put on a high torque starter to help with the hard starting with the timing anywhere close to being on not much help so im alittle lost any help would be great
CrazySCo_hmmthink

Found this today still looking for something to back it up.




I have a '72 351C 2V I am putting in a 56 ford sedan. After some research on the motor specs, I saw the big HP drop on these motors between '71 and '72. One of the changes the factory made was retarding the cam timing 4 deg.
http://www.boss351registry.com/351_Cleveland.htm


just did a compression test and they ranged from 148 to 153 so their on still scratchin my now hairless head one good thing we have over three feet of snow so driving is a ways off yetSCo_hmmthink
How did you determine cam intake installed centerline? Did you degree the cam? I assume it is a 351W. If so is the cam ground for a 351W firing order (13726548) or 289/302 firing order (15426378)? Are you certain the distributor is installed correctly? Is the gap on the pertronics set to spec?Did the engine rotate freely prior to installation? I'm just suggesting things you might look at to eliminate possible causes. Let me know if you find anything. Good luck.

Chuck
Sorry i guess thats one thing I didnt mention was that its a 351 C the cam center line is on I did degree it
(01-24-2011, 11:41 AM)Mach1LloydAb Wrote: [ -> ]Sorry i guess thats one thing I didnt mention was that its a 351 C the cam center line is on I did degree it

Ok. When it does start, how does it run? Does it get hot quickly (really retarded a lot)? If it runs OK could the outer ring on the damper have slipped relative to the inner core. I've had it happen as well as losing the outer ring all together. If you degreed the cam I assume you found TDC with a stop and degree wheel before the damper was installed. It may be stretch but???? If that is not the problem and distributor issues are not the problem that leaves excessive internal friction or starter circuit electrical problems. If the contacts in the solenoid are high resistance (burnt) they can drop enough voltage to cause starting problems. A poor ground would manifest similar symptoms. I hope it is not internal. This is an odd one. Please keep me posted on what you find.

Good Luck,
Chuck
Wow Ok I guess Im not following 4 degrees retarded ? Are you degreeing a cam or are you trying to set your timing to start the engine ? Whats going on ? I need more info. Are you finishing the build of the engine or are you trying to just set things ( timing ect ) to start it ? Please give more info and I will help.
YLWHRSE
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