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  #16 (permalink)  
Old 02-27-2012, 05:31 PM
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im getting it from the driver side in the front of the intake, it was working find till tords the end. stayed at 180 until i was almost done then it got over 200 with the boost saying 20 at idle... just a little cornfusing!

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  #17 (permalink)  
Old 02-27-2012, 07:07 PM
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Quote:
Originally Posted by rvansick123
im getting it from the driver side in the front of the intake, it was working find till tords the end. stayed at 180 until i was almost done then it got over 200 with the boost saying 20 at idle... just a little cornfusing!
68Novass is asking where you are geting your boost signal from. Mine is from the rear of the intake also. Happy that my intake came pre-drilled. That thing is def NOT making 20 lbs of boost at idle. Something has to be wrong, bad gauge. Maybe 20 in lbs of vacuum, but not boost.
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Old 02-29-2012, 09:54 AM
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If I could put in my 2 cents worth. I ran top fuel for about 10 yrs and have a roots blown street rod that has been running since the late 80's with a/c in Florida without ever having any major problems. Number 1 it still escapes me how anyone can run Edelbrocks on a roots blower. Edelbrocks use a metering rod system into the secondary jets and the power circuit is activated when you open the throttle. Vacuum loss causes the spring under the rods to pull the rod out of the jet, in effect making the jet larger and increasing the flow. On a blower motor with the carbs sitting on top of the rotors, when you floor the engine vacuum INCREASES and the rod pulls down tighter into the jet. The higher you turn the motor the longer the fuel is cut off from the secondarys. Hollys can be made to work, Edelbrocks can't, unless you richen the primarys up, which is not the way to do it. Number 2, Boost numbers have absolutely no meaning, on how much power you are producing. Look inside of a top fuel race car and you will never see a boost gauge. Thats because the blowers actual boost can not be determined by a gauge on the motor. A poorly designed camshaft, small valves or a motor that can't get rid of it's exhaust, will show a boost that will knock your socks off. High boost readings are pressure inside the intake manifold that is building up, because the engine can't take the charge. Bigger cubes, a better camshaft, bigger valves etc. will drop your boost numbers and give you more horsepower than you can handle. You will find, that if you have set up your motor correctly on a street car that up to about 3000 rpm you will still show vacuum on your boost gauge, it will start showing boost as the RPM increases.
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Old 02-29-2012, 11:42 AM
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i have a 361 ex FT (i change the orginal cam for an a FE cam) the engine have the original compresion 7,5 a 1, i have a detroit 6-71 blower, i want 7 psi, what relation puley a nedd?
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Old 02-29-2012, 04:56 PM
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boost

i agree the gauge must be bad.maybe the intake took a backfire and the gauge did not like it.i agree on the carbs that a holley is the way to go and what i use.
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  #21 (permalink)  
Old 02-29-2012, 04:59 PM
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Quote:
Originally Posted by jorge-nuviola
i have a 361 ex FT (i change the orginal cam for an a FE cam) the engine have the original compresion 7,5 a 1, i have a detroit 6-71 blower, i want 7 psi, what relation puley a nedd?
go to the BDS website and look at the blower drive chart for engine and blower size and you can get some idea on the drive %.
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Old 02-29-2012, 06:41 PM
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red hot

I have a sbc with a 6-71 in very long project car, time wise that is.
Have enjoyed this conversation very much.
I would like to know if timing is more apt to cause my headers to get red hot rather than a lean fuel problem. I have rejetted the carbs along with other mods.
I don't have the truck driving and haven't been working on it now for about 3 years. But I would like to fire it up and and make all the final adjustments.
I also know the distributor has not been recalibrated for lots of idle advance.
Thank you for your advice, Scot
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Old 02-29-2012, 10:35 PM
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If the headers are glowing hot than It sounds like the cam timing is retarded and the exhaust valve is staying open too late. We used to do that on purpose, it was called " firing in the pipe ". We did it to kill off some of the bottom end when the track wasn't biting well. It happened mostly at night races during the summer the track would get wet and that was a bummer. Late timing plays a part in this also.
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  #24 (permalink)  
Old 03-01-2012, 05:44 PM
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red hot

Thanks Tony Goodstuff for the helpful information. Its nice to hear from someone who knows and not just guessing. It has been a few years ago I think I degreed that cam at 2 degrees retarted, maybe I am the retarded one! Evidently your not supposed to do that.

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Old 03-02-2012, 08:51 AM
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Originally Posted by one off
Thanks Tony Goodstuff for the helpful information. Its nice to hear from someone who knows and not just guessing. It has been a few years ago I think I degreed that cam at 2 degrees retarted, maybe I am the retarded one! Evidently your not supposed to do that.

Nice work, Scot. Very original. I like it.
Tell us more about the engine and the car.
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  #26 (permalink)  
Old 03-02-2012, 05:52 PM
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Thank you for the compliment Nolowrider.
The truck is a 49 Chevy with home built chassis All parts are made at my home shop. The front suspension is steel tubular with adjustable shocks and springs, the power steering rack is a highly modified Honda that can accept control arms as close as 8" apart, the rear suspension is a narrowed 94 Corvette with single link arms to look more old school,all the fluids, vacuum,and wiring run through the frame, the dash is also one of a kind all steel and one of the gauges was built at home too,the pulleys and the belt tentioning system is home built along with a cross flow radiator that has all removable hose fittings, the distributor cap is one of a kind which happens to be the second cap design that I have, the first is the Crossfire.The bolts are all allen head stainless allot of fittings are hand made all sheet metal under the hood is hand made, the top is chopped the bed is all steel no wood the rear fenders are rolled across to each other and lots of other stuff that gets a little boring to mention. If I left something out you would like to know about let me know Thanks, Scot
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  #27 (permalink)  
Old 03-02-2012, 05:54 PM
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Quote:
Originally Posted by rvansick123
im getting it from the driver side in the front of the intake, it was working find till tords the end. stayed at 180 until i was almost done then it got over 200 with the boost saying 20 at idle... just a little cornfusing!
if you followed the good advice above^..the tune up should be in the ball park.You still need a good coolant system to tame a blown big block on the street.Is it warming up at low speed operation or after wot blasts?
Fwiw..a high hp low revving blown big block on the street may require a stock cast iron water pump.Some of the aftermarket units are more suitable for higher winding applications and do not pump as well at low speed like the oem unit does.
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  #28 (permalink)  
Old 03-02-2012, 06:17 PM
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Hey Scot there is something I'd like to ask you about. Tell if you would about your firewall, it looks great.
Tony
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  #29 (permalink)  
Old 03-02-2012, 06:44 PM
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Thanks Tonygoodstuff,
The original firewall is still in place and additional leveling was done with I think 3/8 tubing. What I mean by leveling is that the firewall had reinforcement beading or bead rolling that sticks out above the flat surface of the firewall.
So what was done is that the new sheet metal was laid on top of the the beading and tubing this provided an air gap which provides an insulation from the heat of the engine compartment.
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