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Discussion Starter #1
Hey guys,

I need your opinion on this. Building a stock stroke 360 mopar combo, hoping to push me into the high 11's. Obviously it being a shorter stroke motor its going to need to rev higher to make some power. My LA block is a factory roller block and all along ive wanted to keep it this way since the roller would mean easier maintenance (And possibly more aggressive ramp profiles?). However, Im starting to wonder if staying hydraulic roller is going to limit my goals since from what i understand the lifters are only good to about 6500rpms

Regardless of reliability, what do you guys recommend? Should I stay hydraulic roller and reap the benefits of lower maintenance and more aggressive ramps? Or should I go solid flat tappet so i can rev higher (would I have to bush the lifter bores though?)


Any input you guys might have is appreciated!
thanks!
Matthew
 

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I routinely turn my hyd roller in the 7200-7400 rpm range. I know of several others that run in the 8000 rpm range. I use a billet core cam, Comp stock replacement lifters, and good springs. Nothing fancy.
 

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Discussion Starter #3
I routinely turn my hyd roller in the 7200-7400 rpm range. I know of several others that run in the 8000 rpm range. I use a billet core cam, Comp stock replacement lifters, and good springs. Nothing fancy.
really? that contradicts everything ive heard before

lunati was the only company who told me that I could spin to 6800 with hydraulic roller lifters, but it had to be their lifters, not the stock replacement ones for my motor. Ive talked to quite a few chrysler guys who say the stock roller lifters work just fine, but i dont know of any spinning higher than 6500

Id really appreciate more insight on this guys, so please share your experience or opinions
 

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it had to be their lifters, not the stock replacement ones for my motor.
Let me clear that up. The lifters I used are what Comp Cams sell as a stock replacement. The are miles ahead of a typical replacement lifter.
The Lunati lifters are probably about on the same line as Comp's.
 

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Discussion Starter #5
Let me clear that up. The lifters I used are what Comp Cams sell as a stock replacement. The are miles ahead of a typical replacement lifter.
The Lunati lifters are probably about on the same line as Comp's.
How much of a difference is there between a stock replacement lifter and the ones comp sells? Ive talked to guys using the stock chrysler roller lifters in cams up to 240 at .50" duration and mid 550" lift with no problems, its just the rpm range that im concerned with. I want to be able to use up all the cam and let it pull to 7k if it needs to without worry
 

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The Comp lifter has a stiffer internal spring and tighter tolerances (main differences).

Its not just the valvetrain that determines the rpm range. The heads, induction, and exhaust are the main factors. The cam just ties them together. My car isn't a Mopar (SBF), but that doesn't change the dynamics of it. My cam only has 227*@ .050", but the rest of my combination takes advantage of what it has to offer.
 

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I also routinely turn over 7200 rpms with my hydraulic roller.. My shift lite is set at 7000..

I use Comp Cam link bar lifters, and their 5/16 Hi-Tech oil restricting pushrods..

BTW.. My valve springs measure 215 lbs on the seat..
 

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You'll get a lot of different opinions, but you could always just run a "rev-kit" and you won't have to worry about problems with your hydraulic rollers. (I know they make them for Chevy's, I would assume someone makes them for Mopar as well?) Like has already been stated, just make sure you use a decent set of lifters. You should have no trouble at all going high 11's with a roller cam. That and a good set of heads and you should be embarrassed if you don't see 11's.
 

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Discussion Starter #9
Hey guys, thanks for the input!
I understand its not just the cam and everything has to work together, this has been all planned out with the chassis and the rest of the drivetrain. Only thing left to do is pick the cam. Bullet cams told me that I should only need to spin their grind to 6200 to make the power im after, but skeptical that such a short stroke engine like mine in a fairly heavy car will hit a high 11 with something that doesnt see 6500 rpm plus (or am i just stuck in the past?)

Ive talked to many who have used the stock juice roller lifters in big cam apps, and they have had zero problems. Its just the rpm range of them im concerned with

and yes, i will be embarassed if i dont see 11's as im really hoping i can atleast break an 11.99...ive seen cars with similar combos to mine but with less gear, automatic, milder cam and more basic heads hit closer to mid 11's...its all in the combo i guess
 

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i say stay hyd roller and get bullet to custom grind you a cam. the rpm range of the cam will also vary depnding on your supporting mods such as heads intake headers ect ect. my cam is a comp xe 282 power band from 2500-6500 but stops pulling at around 5500-5800 cause my heads are very restrictive. i'm no expert but from my experiance thats what i discovered.
 

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Discussion Starter #11
i say stay hyd roller and get bullet to custom grind you a cam. the rpm range of the cam will also vary depnding on your supporting mods such as heads intake headers ect ect. my cam is a comp xe 282 power band from 2500-6500 but stops pulling at around 5500-5800 cause my heads are very restrictive. i'm no expert but from my experiance thats what i discovered.
Ive called Bullet and I have to say the grind he chose for me he said id only need to spin to 6300rpms max...something like this

dur at .50 235/245
lift 565/575
LSA 108
Int C/L 104

My heads peak flow at 271 at .550" lift on the intake side, 191 at .550" on the exh.

I trust Mark at Bullet, I just find it hard that being a short stroke engine like what ill have that i dont need to rev up to 7k to get the car to make power enough to where I want to be in the 1/4 mile...I did give him all my specs for the car/chassis, but i cant help but say im slightly skeptical:smt102 Maybe you dont need as an aggressive profile or rev range with the juice roller? i guess its new info thats hard for me to swallow...at the end of the day when i spend that 3-400 bucks on a cam, i just want to make sure its the right one and will do what i want it too
 

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Needs less of a split and more intake duration. Keep that exhaust lobe and see what they have in the low 240 range for the intake. You shouldn't need anymore than a 2 to maybe 4 degree split for that.
 

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The key here is you need to focus on torque, and not get caught up in the high RPM horsepower mindset. Bullet is right, the relatively short duration cam you've listed that they recommend should get you where you want to be nicely, as long as you have the chassis and traction to put the power to the ground for the first 330'. Remember, 10 more ft lbs of torque at 3500 RPM will make your ET quicker than 10 more horsepower at 6500. Plus, your engine will last longer not twisting over 7 grand every pass.
 

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Discussion Starter #14
Needs less of a split and more intake duration. Keep that exhaust lobe and see what they have in the low 240 range for the intake. You shouldn't need anymore than a 2 to maybe 4 degree split for that.
why is this?
 

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The key here is you need to focus on torque, and not get caught up in the high RPM horsepower mindset. Bullet is right, the relatively short duration cam you've listed that they recommend should get you where you want to be nicely, as long as you have the chassis and traction to put the power to the ground for the first 330'. Remember, 10 more ft lbs of torque at 3500 RPM will make your ET quicker than 10 more horsepower at 6500. Plus, your engine will last longer not twisting over 7 grand every pass.
Well the car is a stickshift, so everyone is trying to tell me ill be handicapped off the bat from that...obviously will be harder to do than an auto, but not impossible imo like some make it look

I would rather not spin it to the moon if possible, i guess i just find it hard to understand how the power can be made without doing that lol
 

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I had a 69 chevelle with a throwdown 355.
10:1 comp
stock bottom end
750
rpm
TFS twisted wedge G1 heads 271/200cfm (home ported)

got a bullet HR 232/238 on a 110lsa cam
Shifted at 6500 ran 12.31 @ 110.6 without tuning
but it wanted to rev higher, once shifted it at 6700 still pullin strong, just didnt wanna shifted higher because of stock rods, and it was just a cruiser. I think with tuning and higher shifts high 11s would be easy, and the car wasnt set up for the track... more of a cruiser with AC and OD and all.
My point is the cam Bullet recommended will love to rev way more then 6300, especially with the added exh. duration. Put some spring pressure on it and rev it to 7000! (if it wants it)
 

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Discussion Starter #17
I had a 69 chevelle with a throwdown 355.
10:1 comp
stock bottom end
750
rpm
TFS twisted wedge G1 heads 271/200cfm (home ported)

got a bullet HR 232/238 on a 110lsa cam
Shifted at 6500 ran 12.31 @ 110.6 without tuning
but it wanted to rev higher, once shifted it at 6700 still pullin strong, just didnt wanna shifted higher because of stock rods, and it was just a cruiser. I think with tuning and higher shifts high 11s would be easy, and the car wasnt set up for the track... more of a cruiser with AC and OD and all.
My point is the cam Bullet recommended will love to rev way more then 6300, especially with the added exh. duration. Put some spring pressure on it and rev it to 7000! (if it wants it)
what about the lifters though? what lifters were you using?

would the higher spring pressures help keep the lifters from pumping up?
 

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stock gm lifters, it was a factory roller block.
SB valves were 2.02/1.60s so theyre not heavy.
spring that is around 160/400 open should be plenty to turn 7000
 

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Discussion Starter #19
what is the advantage of a hydraulic roller over a solid flat tappet other than cam break in?
 

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what is the advantage of a hydraulic roller over a solid flat tappet other than cam break in?
Much faster ramp acceleration rates on the cam are possible. Roller cam with same duration/lift will have more area "under the curve" than the same spec'd solid lifter cam.
 
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