Twin turbo factory

When ordering the solid lifters, do you just ask to have edm holes cut in or are some aready cut in . What would be a good company to contact for 300 lifters with edm holes
 
After working with Pullin 300’s engine and cam combination, I’m going to recommend a solid lifter cam profile close to the cam that was used in the Newcomer turbo Jeep engine as you originally suggested.
Intake and exhaust lobe .050” durations around 240 degrees on a 112 LSA with as much valve lift as possible.
Also looking at double valve springs rather than single Beehive springs.
 
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sixtseventwo4d said:
I had the understanding that the beehive design in itself would help with valvetrain stability. and provide the needed spring rate.
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A single Beehive spring does have advantages over a regular single spring but we still had problems with an aggressive hydraulic profile cam with Beehives.
Sometimes you just get tired of fighting a problem all season and are willing to go back to the old “tried and true”
 
I was considering the Beehive springs for there stability and the larger weight difference. I was under the impression that engine would Rev quicker with less upper valve train weight, but I am 100% for less problems . Tried and True is good. Then would you use spring provided with pro max head with inner spring added .
 
The springs that come with the Promaxx head have a 400 lb/in spring rate which is enough for a solid lifter cam. Adding another spring would make the spring rate too high.

The problem with the springs that come with the head is the seat pressure is only 100 lbs which is too low.
You would need a double spring that has around 150 lbs of seat pressure at 1.800” and a 400 lb/in spring rate.
 
Do I need the closed and intake spring pressure around 150 lbs. or could the pressure be different on intake or exhaust maybe use different pressure springs. If so would that cause a valve train problem. There is also the angle valves that look like Beehives . I will start calling spring company’s. After your advice.
 
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You will need to have the head and valves so you can measure the retainer height on both the intake and exhaust valves to determine the installed spring height.
Then you can look through the online catalogs to find a set of springs to match.

Both intake and exhaust valve springs should be the same and installed at the same height.

I can help you with spring selection.

The cam supplier usually specifies the open and closed spring pressures for the cam but they aren’t always right concerning the Promaxx head on a 300 six versus rpm.
 
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Ok would I order the cam and solid lifters first, then the valve springs to match cam lift and well push rods last. If so which cam should I be looking at or ordering, you seem to speek very highly of Jones cams. I still haven’t received any word about when my cyl. Head will be shipped. From what I have seen photos of cyl. head on forum, the CNC machining looks a little rough and will need some smoothing out.
 
Red rose racer said:
Ok would I order the cam and solid lifters first, then the valve springs to match cam lift and well push rods last. If so which cam should I be looking at or ordering, you seem to speek very highly of Jones cams.
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Yes, you would order the cam and lifters first then determine the valve spring specs.
Once the head is on, you figure out the rocker arm geometry which will determine the pushrod length.

If Mike Jones has cam cores he would be a good source for cam and lifters.
Crower cams would also be a good source for the cam.
 
pmuller9 said:
Yes, you would order the cam and lifters first then determine the valve spring specs.
Once the head is on, you figure out the rocker arm geometry which will determine the pushrod length.

If Mike Jones has cam cores he would be a good source for cam and lifters.
Crower cams would also be a good source for the cam.
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That was an intake and exhaust lobe .050 duration at around 240 degrees and a LSA of 112 degrees. Flat tappid cam . how much lift would that be with 1.6. Or the 1.73 Roller lifters And we’re would peak torque be
 
Red rose racer said:
That was an intake and exhaust lobe .050 duration at around 240 degrees and a LSA of 112 degrees. Flat tappid cam . how much lift would that be with 1.6. Or the 1.73 Roller lifters And we’re would peak torque be.
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Looking for peak torque at 4000 rpm to make good upper rpm power but still have good turbo response off the line.
We are getting peak torque at 3600 rpm with a 232 duration cam with the Promaxx head so figure something around 240 to move the peak torque up another 500 rpm.
It would be good to have at least .550" valve lift with a 1.6 ratio rocker arm which would give you an actual 530" valve lift after you subtract the tappet clearance.

The Harland Sharp roller rocker arms come in a 1.6 or a 1.75 ratio.
 
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If anything (as a concept), increasing exhaust valves would take priority over intake valves. Step your build plans as @pmuller9 is outlining, as the goals > plan > build are critical to success. First on the list is to choose your fuel, so the build centers on that.

At this level, EFI is virtually mandatory for tight control, and added functions desirable to reliability and performance. For example, not only can you balance the cylinders for fuel and power (weakest cylinder limits entire engine potential), but also include features such as small-shot N2O control from the same controller, often used to stand torque up on launch, while spooling the turbos quickly, so no waiting and no extra heat from anti-lag. :sneaky:
 
The .550 value lift sounds good , if I remember valve springs and lift , with the set 1.800 Val. Spring height set , with the longer valves the max lift possible should be around .575 before coil bind and or valve train problems. I have been thinking about 5700 to 60- 6200 RPM level
 
Red rose racer said:
The .550 value lift sounds good , if I remember valve springs and lift , with the set 1.800 Val. Spring height set , with the longer valves the max lift possible should be around .575 before coil bind and or valve train problems. I have been thinking about 5700 to 60- 6200 RPM level
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Just looking at Comp and Crane double valve springs, I see springs set at 1.800" and with around 400 lbs/in with coil binds closer to 1.150" or less.
That would give you at least .600" travel with .050" coil clearance.
 
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