Help me find the umph in my 360

-
dustyaman said:
My problem is I feel like it's just sluggish and should have way more power.
Click to expand...
I googled that 1798 cam and found it
285/285/112 480 lift and [email protected]
In at 108(4* advanced) That will get you
109.5 degrees of compression and just 101.5 of power extraction. and most importantly an Ica of 70.5.
At say 8/1 compression ratio , the Wallace Calculator predicts a CCP of just 113psi and a V/P index of a mediocre 91
If your Compression tester is accurate at 140psi then your Scr has to be higher or your Ica earlier.
That V/P of 91 is about as good as a stout 225 slanty, and that is exactly why your engine is "sluggish".
If it was my engine, and I got that cam spec right, then
I'd take that engine apart and start over. But since it's not mine;
I would just swap that cam out for something much much tamer, install a modest stall convertor, and get me some more rear-gear. Now we're talking.
Ignition timing will not fix this
carburation will not fix this either
you need more cylinder pressure, a lot more and I believe your Compression tester is not accurate, unless you are 1000 ft below sealevel and have a 9/1 Scr....... lol.
That cam is not currently your friend.
 
Just some constructive criticism here:

The geometry on the Lokar throttle cable is off a bit pulling in a straight level line (Blue line).

Mopar Factory throttle cables with the proper 1486 adapter pull down hill in a bit of an arc to full open the secondaries (Red line).

The return spring is now on too steep of an angle and needs to be more in line (Yellow line) for smooth return action.

20230710_000754.jpg


____________

'76 D100 Edelbrock / 727 kickdown:

Screenshot_20230710-001817_Gallery.jpg


Things are pulling more in line and the proper geometry.

☆☆☆☆☆
 
If the camshaft and lifters are broken on good, there's no way I'd risk a camshaft change. That engine can be substantially improved, IMO by advancing the camshaft timing. I wouldn't be a bit afraid to advance it down around 104 or even 102 ICL. It can make a huge difference.......ESPECIALLY if it is retarded from zero right now. It'll turn it into a different engine.
 
The problem is probably two fold:
- your power shifter: the cam. What a cam like that does is shift the power. It taketh from the low end & giveth to the top end....which is what you are feeling.
- comp ratio. To try & claw back some of the lost low end, you need to raise the CR.

I would advance the cam at least 4* [ 8 would be better ]. This would make an improvement you would feel, but it is not a night/day difference.

Congrats on using a great carb & your tuning skills with ign timing [ plenty of initial + MVA ].
 
I do not see any problem with the angle or location of the throttle return spring. Whether that position was by design or accident, it is very clever, as long as it doesn't bind/foul anything. It will return the carb to idle [ safety feature ], while not being overly strong at WOT.
 
dustyaman said:
Here is a picture of the carb

View attachment 1716112620
Click to expand...
Looks like your kickdown cable adjustment at the bracket is maxed out. I would give it a bit more slack. Be sure the kickdown lever on the trans returns fully to the front after full throttle. On mine I had to make a bracket and put a spring to the kickdown lever to make sure it returned properly. The springs that came with the Lokar kit did fine for returning the throttle lever to fully closed but the kickdown return needed some help.
 
RustyRatRod said:
I think the Lokar stuff is one of the biggest frauds ever on hot rod guys. I've seen a lot of it. It's chinsey as hell and it sucks. The factory stuff works far better. You got that right!
Click to expand...
I've had just the opposite experience. The Lokar kit installed easily and worked perfectly. If folks have the factory intake, then factory throttle & kickdown would be fine. Few of us have original stuff though.
 
Well might be another issue that occurred. I drove the car to work this morning and was just cruising. Not sure what had happened but heard a bunch of metal noise occur all of a sudden like it bent a rod or something. It was only driving around 2500 rpm. I was 1 Mile from work so limped it there. Opened the hood up and the noise is coming from the left side of the engine. Can't tell from where yet. I will give details when it starts becoming daylight and I can investigate further.
 
I'm curious (sorry if someone asked) Your block is made to use a roller cam, OEM lifters can be bought for $100 a set (ish) and the cams aren't that expensive.. why a flat tappet?

P.S. just read bout the noises... hope it's not serious :( Perfect block for a stroker though :)
 
Icetech said:
I'm curious (sorry if someone asked) Your block is made to use a roller cam, OEM lifters can be bought for $100 a set (ish) and the cams aren't that expensive.. why a flat tappet?

P.S. just read bout the noises... hope it's not serious :( Perfect block for a stroker though :)
Click to expand...
The engine when I got it still had hydraulic flat tappet and stamped rockers. So I just went with another flat tappet. But I started the engine back up and it didn't make the noise until it got warm again. It definitely sounds deep. This sucks.
 
dustyaman said:
The engine when I got it still had hydraulic flat tappet and stamped rockers. So I just went with another flat tappet. But I started the engine back up and it didn't make the noise until it got warm again. It definitely sounds deep. This sucks.
Click to expand...
well hopefully nothing serious... just a few hours to pull it apart and find out.. if it's dead feel free to send me the block :)
 
It's weird I didn't hear the noise when I drove it back home. Granted I was only going 25 mph at low rpm. But I hoping it's something easy. Tonight I will pull the valve covers and check the upper valve train. I might just take the engine apart. And re degree the cam also. Or get another cam. Is there a better cam that works well with the stock converter and transmission but still gives a great power band?
 
Last edited:
dustyaman said:
It's weird I didn't hear the noise when I drive it back home. Granted I was inly going 25 mph at low rpm. But I hoping it's something easy. Tonight I will pull the valve covers and check the upper valve train. I might just take the engine apart. And re degree the cam also. Or get another cam. Is there a better cam that works well with the stock converter and transmission but still gives a great power band?
Click to expand...
I am not a cam expert but i would go with a bit lower duration (i believe yours was 228@50) with a stock converter you want that power in low a little lower.. I would also do a little lower LSA.. but i'm sure some cam expert will have more help for you soon enough :)
 
At 8:1 compression i'd use the comp XE256 and don't go too tall with your rear tires. You'll lose every
parking lot or internet race but won't be able to stop smiling when you drive it or launch it beside a big
block at a stop light.
 
and then after you go comp you can replace it 2 hours later with a cam/lifter set that doesn't go flat on first startup :)
 
Ouch...looks like you've had bad luck with comp. OK how about an old Melling replacement at
.429 and .447 wit .204 / .214 duration. You'll melt the tires for half a block!
 
ir3333 said:
Ouch...looks like you've had bad luck with comp. OK how about an old Melling replacement at
.429 and .447 wit .204 / .214 duration. You'll melt the tires for half a block!
Click to expand...
Is there a part number for that cam?
 
Sure, it's a generic older replacement grind. Less duration than the original that was .429 / .447 and
.210 / .220. Provides more lo end torque. Really strong in a lo compression engine
 
Last edited:
Could send that current cam off to Oregon grinders and get exactly what you want for 1/3 the cost....
 
dustyaman said:
Wouldn't I still have to get new lifters because it would be a basically new grind?
Click to expand...
yes... but you could get good lifters from a decent company and NOT COMP...... Comp has serious issues with lifters wiping cams (just do a quick search anywhere and you will see it) I wouldn't trust them with anything at this point.
 
Icetech said:
Could send that current cam off to Oregon grinders and get exactly what you want for 1/3 the cost....
Click to expand...
Wouldn't I still have to get new lifters because it would be a basically new grind?
Bewy said:
The problem is probably two fold:
- your power shifter: the cam. What a cam like that does is shift the power. It taketh from the low end & giveth to the top end....which is what you are feeling.
- comp ratio. To try & claw back some of the lost low end, you need to raise the CR.

I would advance the cam at least 4* [ 8 would be better ]. This would make an improvement you would feel, but it is not a night/day difference.

Congrats on using a great carb & your tuning skills with ign timing [ plenty of initial + MVA ].
Click to expand...
If I did that does it bring the power curve down more with advancing the cam?
 
So with you guys saying my mph doesn't match the rpm with my 3.55 gears. Is it the cam causing issues with the torque converter causing it to slip since it's built more for top end?
 
You must log in or register to reply here.
-

Back
Top