What cams are you 540 boys running. My 69 is mostly street, is has a TKO-600 3:73 gears. The Comp Cam hyd-roller I have in it now is .646/.646-254/262 and it cannot be tuned to drive at low rpms without bucking. I pulled a 502 with a healthy cam out of the car (that was fun) and installed this engine and now I have a car that is not fun to drive except when it is accelerating. It bangs the drive line so bad you have to push in on the clutch to stop it. I want a healthy sounding engine. I have posted before about trying to tune it and have not gotten anywhere, maybe a cam switch is in order. Oh yeah it has a 15 lb aluminum flywheel. This thing revs faster than a NASCAR motor. Edd

change the rear gears to 4:10 or 4:33 and first gear becomes good for about 40-foot before hitting second, or change the cam to less duration which will pump up the torque make short work of any tire tread left.

Take it to a chassis dyno, you have tuning issues, a 540 should be able to run fine with a cam that small at low rpms.

I thought it was tuning also, I have tried, a 950hp, 850dp, messed with the jets on both, 2 distributors one vacuum and one mech. When I got done, I did not see much improvement with any combination. I am not brilliant but not stupid either, but I am almost to the point of taking this thing out on a country road and blowing it to junk heaven. (calmed back down now and I type)......There is a chassis dyno in Grain Valley, not to far from here, I will call them and see if I can get a feeling as to if they know what they are doingor not. Thanks Edd

My 540 has a larger cam than yours and I have a manual tranny. I agree you need to take it to a chassis dyno and dial your motor in. I had some issues with my dominator but I never made changes to it as I went with a 750cfm 4150 series. I can drop the car down to less than 20 mpg in 5th gear (1:1 with a 3:42 rear) and it will just pull like a freight train with no stumbling.

HTH,

This is where everyone gets into the issue of *streetable*. We all have differing amounts of what we will accept. A 254/262 hyd cam will be pretty thumpy...I'm assuming it's on a 110 LSA?

My cam is a 266/272 on a 112 LSA, but it's a solid roller and that changes things a lot. It idles clean..and to me it sounds sorta wussy at the red light. You can tell something is up there, but it's not a hardhitting nasty sounding cam to me. But once it turn on..it rocks!

I have a stick trans and 3.07 rear gears. I can lug it down to under 1500 rpm in the higher gears...but it's happier at 2000 rpm or above. I have a Super Victor intake and Dominator..plus 377cc intake ports..so it's not exactly a low speed setup.

What timing curve are you using? What is initial timing and what is it when you are getting the bucking?

To get what you're looking for you may need to widen LSA somewhat to a 112....hate to see you go to a 114. A solid roller will likely have better manners than the big hyd roller...much better!


JIM

Hey Jim and John. I thanks for your posts. This cam is; Lobe seperation 114,
Int centerline 111, Installed @ 110. Do either one of you boys have an aluminum flywheel? I kinda wondered if maybe the lack of weight on the back of the engine may have something to do with it. I have my initial timing at 16-18 and full (36-38) all in at around 2500. As far as the timing curve goes I had 2 MSD distributors one vacuum and the other not, both had the factory settings, whatever that is, neither one made any difference. The bucking starts right at 1900 and gets almost violent any lower, you have to push in on the clutch to get it to stop. It so bad I am afraid it will tear upp the trans or something else in the driveline. John is the 540 you have in the Vette that is in the video you link to? Edd

Good point on the timing Jim.............you should make that video of your car in the burnout box and it's 9.90 run part of your sig !! I swear that 540 revs like a small block and sounds like an angry big block.

Hey Jim and John. I thanks for your posts. This cam is; Lobe seperation 114,
Int centerline 111, Installed @ 110. Do either one of you boys have an aluminum flywheel? I kinda wondered if maybe the lack of weight on the back of the engine may have something to do with it. I have my initial timing at 16-18 and full (36-38) all in at around 2500. As far as the timing curve goes I had 2 MSD distributors one vacuum and the other not, both had the factory settings, whatever that is, neither one made any difference. The bucking starts right at 1900 and gets almost violent any lower, you have to push in on the clutch to get it to stop. It so bad I am afraid it will tear upp the trans or something else in the driveline. John is the 540 you have in the Vette that is in the video you link to? Edd The majority of your problem is that 15 lb.flywheel. Aluminum flywheels just plain don't work well for anything unless you have a ton of gear and a car that is not street driven. You can get by with them if you have a short duration cam but you need flywheel weight to dampen power pulses and smooth out the motor while street driving. That will help a lot with the bucking. I tried one once, in a 375 H.P. 396, but took it out after one day. I had a similar "hard to drive" experience.

The timing curve looks good, that is plenty enough initial........I think Harold may have figured this one out. I have never run an aluminum flywheel.

I thought the links Jim provided in his sig were just pictures, they are links to the videos..very cool.

Harold, if you are right I will buy you the biggest steak you can eat the next time you come to Independence. I will order a flywheel tommorrow and then set upp a time for the chassis dyno. I appreciate all the help and will continue to watch these posts. Oh, buy the way, I was very interested in Jim's wanting to know about the lsa, what does all that add upp to? Thanks Edd

Well, since you're already out to a 114 LSA..that kills that idea. A wider LSA..like 114 vs 108....decreases overlap. It opens and closes the intake valves a little later...and the exhaust valves a little earlier. Less overlap generally helps driveability a lot. Your 254/262 hyd roller on a 114 should thump a little..but not drive that bad in a 540. There must be some other tuning issues. The heavier flywheel will help some I'm sure....I run a steel on in my car that's 26#'s. But you also have to look at total clutch weight and even stuff like a stroker cranks weight. It's all rotating stuff.

I find that mine likes a lot of initial..the more the better. But it can't take too much vacuum. I'm just using the black MSD bushing and th elight springs. Mine idles around 1100 rpm and the advance is already starting to move a little down there..so initial is really around 28* or so at idle with no vacuum. I get the rest very quickly. I don't have vacuum on the dist..but I did on my old one. I had it limited to about 6* additional..that's all I could use before I got lean surge. I have a buddy with a 540 that's been testing and he's at about the same point with his G-force trans (non OD just like mine) and 3.08 gears.

What gear are we talking about on the bucking? Is it in 5th O/D? Or does it do it in the lower gears too?


Thanks for the comments on the videos....you can hear it idle..it's not too radical really. At the track I idle it up a little to make sure it doesn't stumble coming out of burnout box and stuff. It drops another 100 rpm or so on the street. And I don't know about the revving thing John...EVERYONE knows that if the heads are too big they will be lazy to rev!! 377cc ports are way too big to act like that!

JIM

Ditto on what Harold said on the flywheel. I tried one for about a week about three decades ago. Very undrivable. Had to slip the clutch to keep the car from dying taking off but that was with a 2.20 Muncie and a 4.10 rear gear. Anything under 1800 rpm was jerking and shaking.

A flywheel in the 35-40 lb range will take a lot of the pulsating out of it. Don't know if it will take it all out but you will see an improvement.