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Discussion Starter #1
A few of you are familiar with my street/strip car. Here's the engine details:

3.40 stroke
4.145" bore
TFS Highport Heads ("stock" 225 CNC ported) 2.080"Intake, 1.60" exhaust
CP Pistons - 9.3:1 compression
Exhaust Header Primary Size - 1.75"
Intake: Edelbrock RPM-II (75mm Throttle Body)
Turbos - Garrett GTX3582R, (T3 Inlet, 3" Discharge Into Full Exhaust) .82 Exhaust A/R

The turbos are "rated" at 750hp each.

I'm wondering what the YB camshaft gurus think of my camshaft specifications.

Valve duration:
@.006" lift - Intake 294, Exhaust 292
@.050" lift - Intake 244, Exhaust 240
Valve lift w/1.6 rockers - Intake .587", Exhaust .576"

Valve Timing @.050", Cam Installed on 114.0 Intake Center Line
Intake: Open 8 BTDC, Close 56 ABDC
Exhaust: Open 54 BBDC, Close 6 ATDC

Lobe Separation: 114

This is a hydraulic cam using Ford racing OEM style hydraulic lifters. Typical shift RPM is 6600-6800.

The car weighs 3550lbs, has AODE, 3.25 rear with 30" tall tires. With this cam the car has run 8.34 @ 163 with a 1.23 short time, 27lbs boost and using a A/A intercooler.
 

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Looks like the one you have works. I am sure someone will chime in about the reverse split :rolleyes:
 

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Discussion Starter #3 (Edited)
Looks like the one you have works. I am sure someone will chime in about the reverse split :rolleyes:
Hey Cal.

Yea, from everything I've read my camshaft specs makes no sense. Truth is, I've heard a lot of different theories about what works so I thought I would throw my specs out there and see what kind of feedback I get.
 

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Discussion Starter #5 (Edited)
Will the turbos make more power or is that it?
I'm pretty sure there's a least a little more there. The car seems to pick up when I increase the boost but I've always been conservative on running the car, tuning it around the 18-24lbs levels and not just throwing more boost at it.

I've made a 2 "small" changes to the car recently - adding individual EGTs and changing the way the 220lb secondary injectors operate from batch to sequential. After changing to sequential, I saw the EGT spread go down from 250F (1200F - 1450F) between the coldest to hottest cylinders to around 56F (1328F -1384F) at 24lbs boost after I "trimmed" the individual cylinders.

With this information I feel I can now start to push the boost higher safely so I will see where it can go.
 

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Im no cam expert but think you cam is working good. If your looking for more power maybe it should be in the 250's. I know the reverse split is "not what guys do now days" but I've had great success with them. I built a 406" Windsor with high ports and a big single around 2001 and IIRC the can was 264-254 on a 114 installed on a 112. That car went 7:30's with 30lbs at 3200lbs. When I freshened it last year I asked the crew chief if I needed to change it as I picked that out in 2000,2001? He said no it hauls ass and goes on the brake good. Duttweiler is a very smart guy. He knows right off the top of his head how much power you can make with a certain size cam. If you can talk
 

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To him it would be very beneficial. I really like your cars that its a true street car. Not meaning the name of the class but you use that thing. Good luck Brian.
 

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So another good friend of mine fought problems with his turbo deal for 5-7 years always asking about that cam that was in that high port motor. Once he finally quit listening to everyone else and put a reverse split in it, it came around. Car picked up like .5 to the 1/8, goes on the brake way easier just way easier to drive. This is a SBC 23* in a mustang.
 

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So like I said I'm no cam guy but have seen the difference between a reverse split and not prove itself a few times. My friend bought a turbo cam from steve morris for a lron headed big block Chevy with cheap Chinese turbos. It was a 540 and IIRC was like 264/264 on a 114. I found it odd that it was that big for a 100% street car. But the engine is also 540". The car never got finished but I remember steve said we would run out of turbo long before we ran out of camshaft. That was speced for 1300-1500hp.
 

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Discussion Starter #10
Thanks Brian.

Right now my cam (and engine combination) is obviously a compromise that is RPM limited to allow for better street driving and longevity of valve train components. One thing I have learned is that big spring pressures may be necessary for high rpms but are hell on lifters.

I've been through 3 cams in the last 6 years. First was a hydraulic with similar numbers to this one. Used Ford OEM lifters, springs that had around 145lb on the seat and the car ran 8.50-8.6x. Never had a valvetrain failure using this combination.

Went to a solid lifter with a little more lift/duration and what was supposed to be high quality solid roller lifter with oiling for the roller. Spring pressure was 210lbs on seat. The car basically ran the same ET/MPH but eventually I had a roller lifter fail that wiped a lobe.

Now I'm back to a hydraulic cam with Ford OEM lifter but initially left the big valve springs in there. The Ford OEM lifter cup fractured with the much spring after 70 runs so now I have some "Beehive" springs with around 160lb seat pressure. So far 135 runs on engine since then and the valve train components seem to be holding up well though I don't have a ton of street miles since then, only around 2000.

Through all of these variations, the car seems to make close to the same power at the same rpm levels. It's also capable of using a lower pressure spring than a lot of guys would think is needed at 6500-7000 max RPM level.
 

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We've had 100% success rate with isky red zone lifters. I have top sportsman guys running 200 passes a year with 1200lbs open. Those guys would always get a lifter here or there throughout the season. Another engine family that I would get a lifter here or there were my limited lift square lobe engines. These guys run around 200 passes a year also cause they win and go so many rounds. The iskys have stopped my problem with lifter issues with them also. Both engine family's stated had jesels in them. I personally have iskys in my jet boat motor and a new one I'm doing for dragweek.
 

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this combo is working well! But I have to ask why are the

lobes sitting way down on a 114 icl? Seems like valves

opening way later than they could be! Just thinking out loud,

as I went the other direction and added advance. Are those

valve events dot to dot numbers or have you checked them

to be just that? Still, the combo is def working for you, but..

is Tony stock block gonna catch up to you??????
 

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Discussion Starter #13 (Edited)
this combo is working well! But I have to ask why are the

lobes sitting way down on a 114 icl? Seems like valves

opening way later than they could be! Just thinking out loud,

as I went the other direction and added advance. Are those

valve events dot to dot numbers or have you checked them

to be just that? Still, the combo is def working for you, but..

is Tony stock block gonna catch up to you??????
These are the specs right off the cam card, haven't verified them though I did degree the cam in. You know, I went back and rechecked the intake centerline and yes, that's what they are calling for on the cam card. I think I have the cam advanced 4degs, it needed 1 or 2 to reach the 114.

One thing that is weird is this engine never pumps more than around 110-115 on the compression gage. I even went as far as putting another gage on the hose to verify the gage was accurate.

I know that the 9.3:1 compression and late closing intake valve lower the compression, but those numbers have always seemed low to me.:rolleyes:

Guys with stock blocks may catch me, but after several hundred 8 second passes I doubt the stock blocks will be happy...
 

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I do know that some motors that have that lower

cranking psi have awesome DCR's as they come up

on the cam/boost. What's your vac @ idle? Lower than

you thought should be?

yes the stock block combos have an inherent if/when

thing going on yes.
 

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That's not the right intake manifold for a solid roller or enough spring pressure. You have to turn it harder which will require spring pressure, gear, converter change. I don't think your trans will live long shifting much higher rpm. I'm shocked car runs that fast but you need more motor power and boost to be faster
 

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Discussion Starter #16
That's not the right intake manifold for a solid roller or enough spring pressure. You have to turn it harder which will require spring pressure, gear, converter change. I don't think your trans will live long shifting much higher rpm. I'm shocked car runs that fast but you need more motor power and boost to be faster
Yep, I know.

I tried a R-Box on this combo and even with the motor being fairly large at 363ci, the cam and rpms weren't enough to use the R-Box effectively. It ran approximately the same ET/MPH. The peak power was higher but the "power under the curve" was the same. The R-Box killed the bottom end and mid-range also. The car didn't drive as well cruising around at 1500-2300 rpm like it does now. When you combine everything together, it turned out to be a better combination with the RPMII intake. That's why I tell so many guys that unless they are winging it past 7000rpm, the R-Box is just not a good intake, especially for a street/strip car.

But guys still run out, buy one and put it on. Then they drive around convinced the car is faster.....;)

Honestly, I think the car runs faster then many would think it could, especially considering it weighs 3550lbs.

Don't be surprised it I get the car to touch 7.9x sometime in the next year, I still have a few tricks up my sleeve....
 

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Discussion Starter #17
I do know that some motors that have that lower

cranking psi have awesome DCR's as they come up

on the cam/boost. What's your vac @ idle? Lower than

you thought should be?

yes the stock block combos have an inherent if/when

thing going on yes.
At 850-900rpm, the car idles with a vacuum around -4psi.

At 950rpm, it idles with around -4.5psi.
 

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A few of you are familiar with my street/strip car. Here's the engine details:

3.40 stroke
4.145" bore
TFS Highport Heads ("stock" 225 CNC ported) 2.080"Intake, 1.60" exhaust
CP Pistons - 9.3:1 compression
Exhaust Header Primary Size - 1.75"
Intake: Edelbrock RPM-II (75mm Throttle Body)
Turbos - Garrett GTX3582R, (T3 Inlet, 3" Discharge Into Full Exhaust) .82 Exhaust A/R

The turbos are "rated" at 750hp each.

I'm wondering what the YB camshaft gurus think of my camshaft specifications.

Valve duration:
@.006" lift - Intake 294, Exhaust 292
@.050" lift - Intake 244, Exhaust 240
Valve lift w/1.6 rockers - Intake .587", Exhaust .576"

Valve Timing @.050", Cam Installed on 114.0 Intake Center Line
Intake: Open 8 BTDC, Close 56 ABDC
Exhaust: Open 54 BBDC, Close 6 ATDC

Lobe Separation: 114

This is a hydraulic cam using Ford racing OEM style hydraulic lifters. Typical shift RPM is 6600-6800.

The car weighs 3550lbs, has AODE, 3.25 rear with 30" tall tires. With this cam the car has run 8.34 @ 163 with a 1.23 short time, 27lbs boost and using a A/A intercooler.


What block, crank, and rods are you using? Your motor has been holding up for a long time.
 

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Discussion Starter #20
What block, crank, and rods are you using? Your motor has been holding up for a long time.
Dart Eagle Block, Prime 1 crank. I originally had Prime 1 rods, they lasted 725 runs so I upgraded to Oliver rods. The car has 935 passes on it since 2008.
 
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