Can you explain the characteristic of this camshaft.

D

dfarr67

Active Member
This a Erson spec'd hydraulic roller in a oe GM roller block, 385 EFI, with non eo TPI. It is in a 1989 Chev 4x4 pick up with a 700r4, 31in tires, 3.73 diff. Engine spec'd to 9.5:1, AFR vortec alum heads- either my issue tuning for 87 octane or plain doesn't like it- have been running 89 octane since installed. Full exhaust, mid length headers and Y. Oem converter stall.

PART NUMBER 110995-47 GROSS VALVE LIFT INT. 0.510
GRIND special GROSS VALVE LIFT EXH. 0.510
ENGINE 385 cid SBC INTAKE OPEN 37
ROCKER RATIO 1.50 INTAKE CLOSE 73
ROCKER RATIO 1.50 EXHAUST OPEN 83
CAM LIFT INTAKE .340 EXHAUST CLOSE 31
CAM LIFT EXHAUST .340 OVERLAP@ LASH 68
LOBE SEPARATION 112 INTAKE PHASE 108
ADV. OR RET. DEG. 4 ANGLE or CENTERLINE
INTAKE "LASH" DUR. 290
EXHAUST "LASH" DUR. 294 EXHAUST PHASE 116
INTAKE DUR @ .050" 222 ANGLE or CENTERLINE
EXHAUST DUR @ .050" 226
JOURNAL SIZE 1.868 INTAKE OPEN @ .050 3
INTAKE CLOSE @ .050 39
TDC 45 EXHAUST OPEN @ .050 49
EXHAUST CLOSE @ .050 -3
HEEL TO NOSE X OVERLAP @ .050 0
W / .010" CLEARANCE X
HEEL TO NOSE X
W / .010" CLEARANCE X
HOT LASH INTAKE 0.000
HOT LASH EXHAUST 0.000

DEFLECTION INTAKE 0.010
DEFLECTION EXHAUST 0.010
E110995-47 DAVE
RH290/340 CUSTOM HYD
RH294/340 ROLLER
112+4
 
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ok you added info
I wish you stated the true compression and port size used
it should have a mildly noticeable lope in the idle,
and it would be best matched to about a 1900 rpm-2000 rpm stall converter
power should start too come on at near 1400-1700 rpm and it should pull well to about 5500 rpm,
in that 383, and youll probably benefit with a bit larger injectors than stock.
 
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Sorry, site has changed since I have last been on here- posted before complete.

A knowledgeable individual had this to say about my choice.

That's a lot of seat duration, for those .050" durations.
Looks like a very lazy cam, that has too much duration, for the area it has.
 
your dealing with a EFI and tuned port intake, both are designed for maximizing lower rpm and mid rpm torque
your EFI sensors won,t like or tolerate the same cam lobe ramp speeds that a carb fed engine would easily work with.

what are you trying too accomplish , correct or do with the engine?
what is it doing currently your trying to change?
that cams designed to work with a mid rpm and efi sensors


http://garage.grumpysperformance.co...lsa-effects-your-compression-torque-dcr.1070/

http://garage.grumpysperformance.com/index.php?threads/semi-fool-proof-cam-sellection.82/



Duration_v_RPM-Range_wIntakeManifold01.jpg
 
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This is a daily driver.

https://www.airflowresearch.com/190cc-sbc-vortec-cylinder-head/

Sounds like the cam choice was consistent with what I was looking for in a truck that cruises on highway about 2000rpm, also had some towing capability in mind although not often. Intake is FIRST TPI, injectors are Bosch 36 pph. With the added cost of carbon tax here I was looking to change to 87 octane with premium being used for towing- I suspect my tune is going lean rather than being a dynamic compression issue. The cam is in and since it is a fair job- would have to be totally wrong for me to think about changing out- and expensive as Erson supplied a better core on a 4/7 swap. The EFI is speed density right now so I wanted a nice efficient cam, I think if the cam was really out to lunch the builder would have objected. I can understand general specs- but I cannot 'feel' the correct application/behavior of any cam spec- I know the 385 would tame a snotty cam for a 350. Love idle lope but understand those don't play nice with my application- truck is what....6000 lbs. Erson wanted to sell me a bigger cam (give the 383 what it wants- comes to mind), I figured I'd be happier with the smaller choice. Through this drive train it puts 330hp to the wheels. The last tuner said the truck was 'fast'. I asked what he meant- he smiled...on the highway once you hit 3500rpm- the needle is buried right quick with lots more (not that I would drive in that manner;) .

I have a set of 1.6 CC steel rockers I'm thinking about installing on the intake- the heads I think will use the extra bit of lift.

This is what was recommended:
Cam# SBC/Cst/B HR70340-71340-113
224/228 @.050"
.340"/.340" Lobe Lift
113 LSA
4/7 Swap
Steel Billet, w/Iron gear
 
dfarr67 said:
It is in a 1989 Chev 4x4 pick up with a 700r4, 31in tires, 3.73 diff. Engine spec'd to 9.5:1, AFR vortec alum heads- either my issue tuning for 87 octane or plain doesn't like it- have been running 89 octane since installed. Oem converter stall.

With the added cost of carbon tax here I was looking to change to 87 octane with premium being used for towing.
Love idle lope but understand those don't play nice with my application - truck is what....6000 lbs?
...on the highway once you hit 3500rpm- the needle is buried right quick with lots more
Click to expand...

For starters, change the converter to a higher stall speed because of all the reasons you stated above.
 
yeah a stock stall converter won,t function anywhere near ideally with that cam,
Id select a 2000 stall speed, minimum,
but why not call the cam manufacturer and get their input also
 
That would bring up an additional question.
Next year I'll probably change over from the 7747 to the 0411 24X ecu, have everything ready to go, which probably means a 4L60E. Besides cam- converters are another gray area for me- but I was thinking of a well built 4.3L V6 converter would be a reasonable way to go.
 
a well built 4.3L V6 converter would most likely not be built strong enought to handle the ft lbs of torque and strain it would be subjected too, as the larger engine easily far exceeds expected torque potential
 
Billet has been mentioned to me prior- do I need to spend that kind of money on this application. There are many good names out there- what is the experience on who makes a good street oriented efficient product that is reasonably priced? BTW thanks for the good responses.
 
You want a Chevy Truck Tahoe Torque converter.
Vortech 350.
I bought a Hughes version for my 1999 Chevy Tahoe earlier this year.
Working great.
3.42 gears.
Cruise 2000 at 70 mph.
Same as 700R4 a 4L60e torque converter.
Stall just right for slower speed velocity intake ports.
Tows just fine pulling 4000lbs total weight with trailer.

1400 Rpm stall used with all 350 TBI engines High Velocity swirl port heads.
More low end torque.
But Hp is lower than Vortech 350.
 
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https://www.summitracing.com/parts/hup-gm22tow/

$237.99.
A good deal.
Hughes Towmaster.
Made for Chevy and GMC trucks.
Heavy Duty.
Made for street and truck towing abuse.
1800 rpm stall.

I can smoke the tires in my 1999 Chevy Tahoe twin strip Posi several hundred feet.
Tap the brake and punch it.
Let off the brake and foot on the floor.
Rear Tires burn away and 100 mph on speedo.
 
When your towing the fluid gets boiling hot inside of the converter.
Even though it's lockup the TCC Is always slipping a tiny amount.
I have verified by reading input and output speed rpm sensors on a Scanner.
Turbine input shaft speed sensor on 4L60E.
Can not check on a 700R4.

Tow master series pumps more fluid through the Trans cooler.
Gallons per minute flow.
About 4-7 Gpm.

This is lowest cost version
All other GM trans models are $400-1000.
 
As I recall, 700r4 converter is on/off, later 4l60e had pwm but you can program them and modify the trans for o/off which is what I prefer. Different clutch materials- paper, kevlar, carbon....
 
You have to get into the old GM charts but just a few apps got carbon fiber friction TCC clutch.
They are all inferior to aftermarket today from Race suppliers.
I prefer Hughes torque converters with a moderate budget.
Going drag racing I want a Race winning Coan Torque converter.

Truck to drive & tow.
Hughes torque converter my 1st pick.
I use one in my 1999 Chevy Tahoe.
Stock converter sucked.
 
I do have a temp gauge reading temp coming out the trans (converter temp)- it is very mobile and comes up to 190deg at prolonged stops but when moving comes down below gauge 145deg cutoff. Using mix of Amsoil torque drive, GM Dex 4. I've never spec'da converter, I'm hoping it's one of those 'why didn't I do that years ago' king of thing. What is the stock stall of this app. Hughes GM22LTow
 
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dfarr67 said:
I do have a temp gauge reading temp coming out the trans (converter temp)- it is very mobile and comes up to 190deg at prolonged stops but when moving comes down below gauge 145deg cutoff. Using mix of Amsoil torque drive, GM Dex 4. I've never spec'da converter, I'm hoping it's one of those 'why didn't I do that years ago' king of thing. What is the stock stall of this app. Hughes GM22LTow
Click to expand...
More torque the engine has the higher the stall.
I see it flashing from a stop WOT About 2200-2400 rpm.
Transgo Shift kit HD2 I used.
Set up for drag race in Tahoe.
Still Auto shift.
Shifts Hard and fast.
Have to use light throttle for no bang drag race shifts.
 
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