Jeep Strokers

Running the stock 96 cam. What are the lift numbers with the Yella terra 1.7 rockers?

Desertjr wrote:Running the stock 96 cam. What are the lift numbers with the Yella terra 1.7 rockers?

Is this a cheaper option than getting one of the cams usually called for in the stroker stroke recipes?

Depends..I'm buying a new stock cam for around 58 bucks I believe. And 500 for the rockers. So roughly 550 into it, with stock valve train which is nice for wear and such. You could reuse your stock cam here if its good and within spec. I'm option for a 96 cam which was different than my 87 cam, so I must buy awe one to get what I wanted.

Aftermarket cams, usually call for aftermarket valve train. Usually stiffer than stock, more worries of wear and spring pressures ect, from what I've seen it would cost 150-250 for your cam. Another 250 or so for the valve train. And I would hope you wouldn't reuse stock high mileage rockers..those are probably another 80-100 to replace. Some may get away with reusing stock rockers if they are in good shape & low mileage but it's a wear item..probably 300k miles but still. If they have 150k+ on em, I would just replace since your new motor will probably go that far if not further! Less worry of things failing!

Cheaper? Yes and no. For me it worked out about even and I was reusing stock rockers. Didn't make since to me, add in new stock replacement rockers made a aftermarket cam option cost more. I looked at my options and choose. I went this route because the desktop dyno info that I came up with. The stock cam advanced 4* and 1.6 ratio made equal or more power & torque than the aftermarket cams I was looking at. This is also the more efficient route I believe & nice because the roller rockers. Should get more mileage although I know it'll be negligible, it will also have a quitter valve train with rollers. To boot it will also make more power and torque with the roller rockers, so when looking at the dyno comparison I believe the numbers would be even higher!

Here's the comparison

ruffy01 wrote:Same again Desertjr with OEM cam advanced 4*:

Desertjr Comparison OEM Adv 4deg.jpg

I logged out here, logged back in on the other PC & both files are visible here mate.

If you choose an aftermarket cam, I would do the mopar 229. Reason is, it made the very similar if not equal numbers to the others with less lift and duration. You could probably get away with stock valve train with it but I wasn't risking it. That was the cam I was going to run when I decided to switch over actually.
You will see the stock cam advanced 4* with a 1.6 ratio, with a 1.7 ratio it would be even higher than what it shows there. Note its maybe 20ftlbs less at the crank than the others, and around 3900rpm it actually takes off better. And horsepower wise they are all so close, but the stock cam 4* advanced pulls at 3500+ on the others. Again with a 1.7 ratio those numbers would be even higher. Ill see if I can get tuffy to run a simulation with a 1.7 ratio for me. I think with a 1.7 ratio it would show at least a solid 10hp and 10ftkbs higher than all those cams.

Desertjr wrote:Running the stock 96 cam. What are the lift numbers with the Yella terra 1.7 rockers?

Stock '96 cam + 1.7 roller rockers = 0.433" intake valve lift, 0.441" exhaust valve lift

Here's the comparison redone, as requested, Desertjr.
All figures are at 0.050", the '96OEM is adv. 4* with 1.7 Rocker ratio.
One thing not allowed for, the increase in lift will result in slightly greater duration @ 0.050" than is listed, which may move the curves further up in RPM range. I think it would be fairly marginal though. Cheers,
Ruffy.

That graph, the 231 looks the best?

CobraMarty wrote:That graph, the 231 looks the best?

Agreed the last graph with 1.6 ratio showed opposite. Curious what happened myself between the 2. It should of just jumped up in power/torque with a 1.7 ratio right? or is there some physics behind it?

Can you do a 'dyno' chart for-

'96+OEM straight up 1.6
'96+OEM 4* advanced 1.6
'96+OEM straight up 1.7
'96+OEM 4* advanced 1.7

CobraMarty wrote:Can you do a 'dyno' chart for-

'96+OEM straight up 1.6
'96+OEM 4* advanced 1.6
'96+OEM straight up 1.7
'96+OEM 4* advanced 1.7

Shall do

The main difference between the above comparison & the earlier one is the above uses @0.050" figures, the earlier was seat-to-seat. Does make a difference.

As requested: (I've uploaded 3 seperate comparisons, all on one was very hard to interpret)
Please ignore the Curves names at the bottom of each image. The OEM (straight up) name is correct the other has altered data accordingly with title I've placed above each image.

OEM'96 vs OEM'96 Adv 4* Slight gains down low, lose out beyond 3500rpm

OEM vs OEM w/1.7Rockers Slight gains above 3500rpm

OEM vs 1.7Rockers + 4* Adv Very similar to 4* Adv only.

No huge gains according to the Sim. Real life??

Very curious myself..is it worth the extra 500 bucks for the rollers?

Definately feel a difference on a DD. ?10hp and 10tq difference?

380 seems to be worth the gain, let alone the reduction in wear, gain in mileage, and reduction I valve train sound.

ruffy01 wrote:As requested: (I've uploaded 3 seperate comparisons, all on one was very hard to interpret)
Please ignore the Curves names at the bottom of each image. The OEM (straight up) name is correct the other has altered data accordingly with title I've placed above each image.

OEM'96 vs OEM'96 Adv 4*

OEM96 vs 4deg adv.jpg

Slight gains down low, lose out beyond 3500rpm

OEM vs OEM w/1.7Rockers

OEM96 vs 1.7Rockers.jpg

Slight gains above 3500rpm

OEM vs 1.7Rockers + 4* Adv

OEM96 vs 4deg + 1.7Rockers.jpg

Very similar to 4* Adv only.

No huge gains according to the Sim. Real life??

I just realized these were run with a 4.7l setup, not a stock 4.0 which would show the true gains. The bigger motor needs a bigger cam, so with the small cam its actually hiding the true gains.
Rudy will you run those 3 sims again with a 3.935 bore & 3.500" stroke?