351c 4v engine build advice

351c 4v engine build advice

Joined: December 16th, 2003, 1:59 am

December 15th, 2011, 5:29 pm #1

Hi Guys, which one of these cams would work best with my combo? I want some tire roasting torque for the street. My max RPM's may reach up to 6K, but not often. I wont be racing.

Lunati 11101 (Lunati's version of the D2ZZ-A-FOMOCO cam)
http://www.lunatipower.com/Product.aspx?id=1608
or
Crane Cams 520321 (Blueprinted D1ZZ-6250-B Boss 351 camshaft)
http://www.cranecams.com/product/cart.p ... il&p=24493

Car is 1970 Mach 1, 4-speed Close-ratio toploader, 3.70 trac-loc, 26" tires. The engine will be a rebuilt 1973 351c, 9.5:1CR, D1AE 4V CC race prepared heads, D0AE Cast iron 4V intake manifold and stock 4V cast iron exhaust manifolds.

I may also swap out the 4-speed for an Automatic. What torque converter would you recommend?

The car currently has a 333rwhp 354rwtq 351w in it and runs awesome, but its not very street able...and not a Cleveland! I have to rev to 2000rpm when I take off. It sounds mean as ****, but it gets annoying driving in town. Thats also why I'm thinking about swapping to an auto.

Anyway, Thanks for your help. Let me know if you need more info.
Jim

----------------------------------
relocated by tinman

Quote
Like
Share

Joined: December 16th, 2003, 1:59 am

December 15th, 2011, 5:53 pm #2

i would figure out why an engine of moderate power output would not be streetable, at 'only' around 350 hp and with a 3.7, even with a close ratio trans gear you should be able to let the clutch out at idle and let it walk along in bumper to bumper traffic?

otherwise you may be destined to repeat the same results

any idea why the current engine combo won't step off the line?

Quote
Like
Share

Joined: January 26th, 2011, 10:15 pm

December 15th, 2011, 9:34 pm #3

Tinman,

You make an excellent point and I havent given it much thought. I guess I've been taking off at 2K so I dont kill the engine in the street and make myself look like a chump. When I first got the engine running I used an old starter and it would grind the flywheel when I'd go to start it. After I got the car running I was scared to turn it off thinking I might not get her started again and it would leave me stranded. The starter eventually went out, but luckily in my driveway, so I ended up replacing it with a low dollar ($50) mini high torque starter that lasted 1 week. After that, I thought maybe my flywheel ring gear may be warped, but went ahead and bought a new stock starter and installed it. It also started to grind every 5 starts or so, but now it hasnt grinded at all for about 15 starts. So, that's one reason.

The other reason I think I launch at 2K is because of the camshaft. Its a solid lift Lunati 410A1LUN
http://www.lunatipower.com/Product.aspx?id=2254&gid=284
Advertised Duration (Int/Exh): 277/284
Gross Valve Lift (Int/Exh): .562/.565
LSA: 110
RPM Range: 2500-6800

This cam is so radical I cant even use a timing light to set the timing. The entire engine shakes in the engine bay like its ready to jump out and eat you. Maybe it's just me. The 351w is my first engine build and the Mustang is my first real hot rod.

The next time I take it out I'll try to launch at a lower rpm (on a back street) and see what happens. I can cruise through parking lots just fine, but doing the clutch dance isnt a lot of fun.

Thanks.
Jim

Quote
Like
Share

Joined: July 26th, 2002, 1:52 am

December 16th, 2011, 1:49 am #4

does it have a stock distributor with a worn breaker plate ? I've had cars with bigger cams that would pull out at idle in 4th gear . do a full diagnostic on cylinder pressure , carb ,timing etc

you know you can have the ring gear taken off the flywheel and a new one put on at most any machine shop , and it sounds like you need it

Quote
Like
Share

Joined: January 26th, 2011, 10:15 pm

December 16th, 2011, 5:12 am #5

Joe, I've got a new PowerFire dizzy and it seems to work perfect. The engine only has 1200 miles on it so far. I had a shop do a leak down test when the motor was new (Oct 2010) and got the following 1:155, 2:158, 3:165, 4:170, 5:165, 6:155, 7:180 and 8:155. The tech said that after the tune all cylinders were averaging 170-180. Are those good numbers?

When I get the Cleveland built I'll take the flywheel to the machine shop and see if they can balance it along with check the gears. I think your right that the ring gear is messed up. I'll do the same with a flex plate if I decide to go with an automatic.

What size stall should I use with my new combo?

Thanks.
Quote
Like
Share

Joined: March 9th, 2004, 3:37 pm

December 16th, 2011, 4:07 pm #6

Hi Guys, which one of these cams would work best with my combo? I want some tire roasting torque for the street. My max RPM's may reach up to 6K, but not often. I wont be racing.

Lunati 11101 (Lunati's version of the D2ZZ-A-FOMOCO cam)
http://www.lunatipower.com/Product.aspx?id=1608
or
Crane Cams 520321 (Blueprinted D1ZZ-6250-B Boss 351 camshaft)
http://www.cranecams.com/product/cart.p ... il&p=24493

Car is 1970 Mach 1, 4-speed Close-ratio toploader, 3.70 trac-loc, 26" tires. The engine will be a rebuilt 1973 351c, 9.5:1CR, D1AE 4V CC race prepared heads, D0AE Cast iron 4V intake manifold and stock 4V cast iron exhaust manifolds.

I may also swap out the 4-speed for an Automatic. What torque converter would you recommend?

The car currently has a 333rwhp 354rwtq 351w in it and runs awesome, but its not very street able...and not a Cleveland! I have to rev to 2000rpm when I take off. It sounds mean as ****, but it gets annoying driving in town. Thats also why I'm thinking about swapping to an auto.

Anyway, Thanks for your help. Let me know if you need more info.
Jim

----------------------------------
relocated by tinman
Hi Jim,

Your current combo (334rwhp) is very stout for a street car. It will be very difficult to get that kind of power from a 4V cleveland with exhaust manifolds unless you are very experienced and get a custom cam ground. You need headers. I went down this road myself. I can tell you that you will be very dissapointed in the performance of the build if you don't include headers in your planning. Others may tell you it is doable, and I'm sure someone can do it. I couldn't.

Good luck,
James P.
Quote
Like
Share

Joined: December 16th, 2003, 1:59 am

December 16th, 2011, 6:14 pm #7

the Crane is single pattern, the intake & exhaust lift & durations are the same... not the best plan for use with exhaust manifolds

the Lunati is a split pattern, the exhaust has more duration to help compensate the stock manifolds
hands down better choice than the Crane if not using headers

the factory Cobra Jet torque converter was rated at 2800 rpm
probably better to aim for 3000 than to get a dog 22 or 2500 converter that doesn't make 1700

i'd check for vacuum leaks & go over the firing order on your current engine, it should have a nice rumpity idle but that's about it. unless you're running a tunnel ram or have a tuning / carb issue it should run fine off idle with a manual trans

messed up valve lash will show up most at idle & low end

there'll be phantoms, there'll be fires on the road... and the white man dancing
Last edited by tinman351 on December 16th, 2011, 6:15 pm, edited 1 time in total.
Quote
Like
Share

Joined: October 7th, 2004, 8:30 pm

December 16th, 2011, 6:16 pm #8

Hi Jim,

Your current combo (334rwhp) is very stout for a street car. It will be very difficult to get that kind of power from a 4V cleveland with exhaust manifolds unless you are very experienced and get a custom cam ground. You need headers. I went down this road myself. I can tell you that you will be very dissapointed in the performance of the build if you don't include headers in your planning. Others may tell you it is doable, and I'm sure someone can do it. I couldn't.

Good luck,
James P.
Jim,
You should be able to time it with a light. It is possible that your outer ring on your harmonic balancer may have spun and your timing marks are out of sync. If so, your timing might be retarded which would make it rougher idling and hard to launch.

James
Quote
Like
Share

Joined: July 26th, 2002, 1:52 am

December 16th, 2011, 6:37 pm #9

Joe, I've got a new PowerFire dizzy and it seems to work perfect. The engine only has 1200 miles on it so far. I had a shop do a leak down test when the motor was new (Oct 2010) and got the following 1:155, 2:158, 3:165, 4:170, 5:165, 6:155, 7:180 and 8:155. The tech said that after the tune all cylinders were averaging 170-180. Are those good numbers?

When I get the Cleveland built I'll take the flywheel to the machine shop and see if they can balance it along with check the gears. I think your right that the ring gear is messed up. I'll do the same with a flex plate if I decide to go with an automatic.

What size stall should I use with my new combo?

Thanks.
when the shop did the first cranking test the numbers ranged and I have a feeling the carb was rich in at least the lower circuits at that time , because the tune up fixed it . It's not just the top number you gotta watch though, you have to watch the gauge it should clear 100 on the 1st stroke and only take a couple more to peak out.

If you say the diz is good I'll take your word for it but , again nuances, when timing with a light does the timing mark appear stable or does it jump all over ? what is your timing at idle ? I use 10* or more and about 36* total in by 3000 rpm .

I dont know who can just balance a flywheel , it has 28 ounces already in it even if they do balance it the engine could be worse off than it is now because they didn't balance the total package.

It also sounds like you may have alignment "issues" with your starter/ring gear . have you got another bellhousing ?

cant make any reccomendations on a tq verter . I'm a stick guy

Quote
Like
Share

Joined: December 16th, 2003, 1:59 am

December 17th, 2011, 9:06 am #10

Jim,
You should be able to time it with a light. It is possible that your outer ring on your harmonic balancer may have spun and your timing marks are out of sync. If so, your timing might be retarded which would make it rougher idling and hard to launch.

James
http://www.gethoned.com/process.html

there'll be phantoms, there'll be fires on the road... and the white man dancing
Quote
Like
Share