bad choice?
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
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From: tomahawk wisconsin
bad choice?
ok another cam question..........
would the comp cam XR276HR be a bad choice for a 383 with a ported tpi intake?
adv. duration is 276-282
@.050 224-230
.502 .510 lift
L.S. 110*
would the comp cam XR276HR be a bad choice for a 383 with a ported tpi intake?
adv. duration is 276-282
@.050 224-230
.502 .510 lift
L.S. 110*
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
Likes: 0
From: tomahawk wisconsin
Originally Posted by crheinish
Yes, what is your goal for the car? Then we can help you.
I have the motor together and running but it just isnt making much power at all.I also have a top end problem that seems to be impossible to figure out. it seems to run good until 4500-5000 rpms then it falls on its face. now I have been able to run it to 6000 a few times so the problem seems intermittent.
I have replaced all the ignition and the fuel system checks out great also.I also ran it with a scanner hooked up and everything seems good to go.
I have had a chip burnt for it, then I dynoed it and got some a/f readings and it runs pig rich after 3600 rpms.it just steadly fell on the dyno graph below 10.1.........so I sent the graph to the tuner for refrence and got a new chip but the problem still persists.I havent stuck it on the dyno again because I think it would be a waste of money.
I dont know where the problem could be because I have went over everything two or three times.and I know the cam was degreed in right also.
does any-one have any other ideas?this car is driving me close to selling it or something soon.
oh ya its a 91 also.
Team Owner
Joined: Sep 2001
Posts: 62,127
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
You wont get the full power that cam can give with a ported TPI on it, so no i wouldnt use it. Something more like the Accel 211 or Tpis ZZ9 if you keep TPI.
Burning Brakes
Joined: Nov 2002
Posts: 1,239
Likes: 1
From: Las Vegas NV
Don't sell the car. It sounds as though you have 2 issues. 1 if you ever want to make power past 4800rpm you have to ditch the TPI intake. There is no way around it. The Super Ram, Steathram, and LT1 intakes will get you to 6K. Your second issue is your rich condition find that and you will have a great car to drive evertday. BTW list your mods please.
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
Likes: 0
From: tomahawk wisconsin
balanced eagle rotating ***. with srp pistons all forged. 10.1 compression
Long tubes
113 heads ported with 2.02-1.60 valves
986-16 comp springs and 10* retainers and locks and cam
bbk throttle body,and ported plenum and base.
2500 rpm stall
high vol. oil pump
1.6 R/R but not on the car.I went back with stock for now.
even though the intake is still stock it should pull above 5 grand right?I thought it would just stop making power at about 4500 or so?also I believe the rich issue is taken care of now.and the lt1 intake would have to be modded to replace my tpi wouldnt it?
Long tubes
113 heads ported with 2.02-1.60 valves
986-16 comp springs and 10* retainers and locks and cam
bbk throttle body,and ported plenum and base.
2500 rpm stall
high vol. oil pump
1.6 R/R but not on the car.I went back with stock for now.
even though the intake is still stock it should pull above 5 grand right?I thought it would just stop making power at about 4500 or so?also I believe the rich issue is taken care of now.and the lt1 intake would have to be modded to replace my tpi wouldnt it?
Last edited by ar91c4; Apr 29, 2005 at 03:28 PM.
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
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From: tomahawk wisconsin
Originally Posted by GeosFun
the 110 LSA might give you a problem. Most TPI/FI systems seem to like 112 LSA's. The former should cause a rougher idle and maybe smog compliance prob's.
I took the car out again with the fuel gauge hooked up and at wot it lost fuel pressure.I read a post before I left about c4s cutting out below 1/4 tank of gas.well it just so happens I havent had the car above half since the new motor, so I stoped and got gas and ran it at wot again.well I got no fuel pressure drop and the car shifted out at 6000 rpms like it should.
I have spent about 5-600.00 on this problem and it was as simple as a bit of fuel in the tank..
so now I guess its back to the dyno for some real pulls and some more a/f readings so I can get this thing tuned properly.
the thing that gets me is it never did this with the old l98 in it.I guess more g's slosh it to the back at wot..
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Instructor
Joined: Mar 2005
Posts: 208
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Originally Posted by ar91c4
well I think I got it.
I took the car out again with the fuel gauge hooked up and at wot it lost fuel pressure.I read a post before I left about c4s cutting out below 1/4 tank of gas.well it just so happens I havent had the car above half since the new motor, so I stoped and got gas and ran it at wot again.well I got no fuel pressure drop and the car shifted out at 6000 rpms like it should.
I have spent about 5-600.00 on this problem and it was as simple as a bit of fuel in the tank..
so now I guess its back to the dyno for some real pulls and some more a/f readings so I can get this thing tuned properly.
the thing that gets me is it never did this with the old l98 in it.I guess more g's slosh it to the back at wot..
I took the car out again with the fuel gauge hooked up and at wot it lost fuel pressure.I read a post before I left about c4s cutting out below 1/4 tank of gas.well it just so happens I havent had the car above half since the new motor, so I stoped and got gas and ran it at wot again.well I got no fuel pressure drop and the car shifted out at 6000 rpms like it should.
I have spent about 5-600.00 on this problem and it was as simple as a bit of fuel in the tank..
so now I guess its back to the dyno for some real pulls and some more a/f readings so I can get this thing tuned properly.
the thing that gets me is it never did this with the old l98 in it.I guess more g's slosh it to the back at wot..
I have a walbro fuel pump and when the tank gets below 1/2 full I already plan on going to the gas station. All it takes is one highway jog to 100+ to virtually knok off a few ticks on the gas guage.
Big hp cars suck gas at wot and with the g's and the virtual squat the car does when you drop the hammer you want to keep your tank full.
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
Likes: 0
From: tomahawk wisconsin
Originally Posted by bigcityvette
I have a walbro fuel pump and when the tank gets below 1/2 full I already plan on going to the gas station. All it takes is one highway jog to 100+ to virtually knok off a few ticks on the gas guage.
Big hp cars suck gas at wot and with the g's and the virtual squat the car does when you drop the hammer you want to keep your tank full.
Big hp cars suck gas at wot and with the g's and the virtual squat the car does when you drop the hammer you want to keep your tank full.
Instructor
Joined: Mar 2005
Posts: 208
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I personally have never expierienced any problems with running low on fuel, even down to 3 gallons in the tank. Only thing is the fuel is used to cool the pump so I like to keep her at least 1/3 full at all times.
Burning Brakes
Joined: Aug 2004
Posts: 1,110
Likes: 1
From: Geneseo Illinois
St. Jude Donor '06
Originally Posted by ar91c4
pulsator??where exactly is that located?
The pulsator is just above the fuel pump. The gas flows from the pump thru the pulsator and out of the tank.
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
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From: tomahawk wisconsin
Originally Posted by dock351
The pulsator is just above the fuel pump. The gas flows from the pump thru the pulsator and out of the tank.
Burning Brakes
Joined: Nov 2002
Posts: 1,239
Likes: 1
From: Las Vegas NV
Pull it out with the fuel lines connected, then turn the key to pressurize it to find a leak. Change the sock on the end of the pump while you have it out.
Last edited by crheinish; Apr 30, 2005 at 12:54 PM.
Thread Starter
Racer
Joined: Jan 2005
Posts: 315
Likes: 0
From: tomahawk wisconsin
Originally Posted by crheinish
Pull it out with the fuel lines connected, then turn the key to pressurize it to find a leak. Change the sock on the end of the pump while you have it out.
thanks.
Burning Brakes
Joined: Nov 2002
Posts: 1,239
Likes: 1
From: Las Vegas NV
well your in luck becase the c4 fuel pump is the easiest i have ever had the pleasure of changing. pull the fuel door off. then approx 10 bolts around the fuel pump assembly, and out it comes. probably take about 10 minutes to get it out.