bad cam?

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novacaine
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bad cam?

#1 Post by novacaine » Wed Feb 26, 2014 5:22 am

Has anyone every had a cam that was bad, like maybe ground wrong? I have a 454 that I put togather with a used cam I bought. It was the same cam # I have ran before. The 454 had oval port alum heads with this roller cam and it degreed. When I ran it had a great burn out but would run up to around 5 grand and stay there. I thought the heads wasnt flowing right. So I sent the cam to bullet and had it reground. I put it back in the 454 now with 13.1 pistons from 10.1's. I put a set of brodix BB2 heads and degreed it and it ran the same way. Great burnout and woulnt make any more rpms after around 5 grand. I pulled the engine and switched cams and gona try it. But has anyone ever run into this before?

bracketchev1221
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Re: bad cam?

#2 Post by bracketchev1221 » Wed Feb 26, 2014 7:37 am

Even the wrong cam will go past 5000. Check the valvesprings, check for interference with the valvetrain. Check the fuel system. It is very unlikely that the cam you have is stopping at 5000.

novacaine
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Re: bad cam?

#3 Post by novacaine » Wed Feb 26, 2014 6:27 pm

I checked the valve train and replaced the fuel regulater. I had a 496 in and pulled it out and dropped this one in. Its funny that two differant set ups with the same cam runs so bad. That is the only thing that is the same. I just changed the cam and just started it. Im gona try it out this weekend.

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mytmouz
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Re: bad cam?

#4 Post by mytmouz » Thu Feb 27, 2014 12:35 am

I personally think if something was wrong with the cam , Bullet would have found it...
Trucks are for haulin...

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novacaine
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Re: bad cam?

#5 Post by novacaine » Thu Feb 27, 2014 5:50 am

I will call bullet and see but if they just ground it off from where it was at it would stay the same. All I know is I have built this engine twice with differant heads pistons and rods and still have the same issue.

novacaine
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Re: bad cam?

#6 Post by novacaine » Wed Mar 05, 2014 6:31 am

I changed the cam and that didnt fix it. I have no Idea what to do next. The only thing I didnt change was crank, block and timing set. But it did degree so I dont like it would be that.

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Re: bad cam?

#7 Post by John_Heard » Wed Mar 05, 2014 9:04 am

Have to wonder if something else isn't going on, running out of fuel, bad/weak valve springs, weak ignition, etc.

novacaine
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Re: bad cam?

#8 Post by novacaine » Thu Mar 06, 2014 5:00 am

The springs was new last season. I put a new fuel regulator on it with a bypass. When I warmed the car up and got in to it it ran fine. But when under a load and down the track it wouldnt open up from the start. It ran a 6.84 first pass, 2nd it went a 6.69. The Msd box is 2 seasons old but no issue's with it just pulled the 496 and dropped this in. Seems funny its starts fine and can set the timing but wont run under a pull.

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Re: bad cam?

#9 Post by John_Heard » Thu Mar 06, 2014 7:47 am

I think I'd look at ignition and fuel. Do you have a fuel pressure gauge on it? Can you tell what pressure is has when it's falling off?

What do the plugs look like? How much plug gap? Did it run any better on fresh plugs vs those with more passes? How old are plug wires? Have you checked out the cap/rotor etc. looking for arcing?

Gonna take some detective work to find this I assume.

novacaine
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Re: bad cam?

#10 Post by novacaine » Thu Mar 06, 2014 7:54 am

I did take off two holley regulators and put on a 3 port with a return. I thought that would be better to use then the two holleys. I set it at 7 lbs, But it under the hood at the reg. I could get another one and put it in the car. Its just seems odd that all I did was pull a motor out and put it in. The MSD was fine and new plugs gapped at .040.The fuel regulator might be the issue.

novacaine
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Re: bad cam?

#11 Post by novacaine » Thu Mar 06, 2014 7:59 am


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John_Heard
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Re: bad cam?

#12 Post by John_Heard » Thu Mar 06, 2014 8:08 am

Why did you have two holley regulators on it? Is it dual carbs? The car ran ok with the Holley's and this issue started when you changed to the new regulator? (Along with other stuff I assume?). Never heard of professional products, sounds like some of that Chinese stuff?

Can you describe your full fuel system setup?

Spark plug gap is excessive, no need for wide gaps on a race car, pull that back to say .030. But not at the same time as with other changes. Avoid shot gunning this, one change at a time when possible so you can figure out what the problem was.

novacaine
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Re: bad cam?

#13 Post by novacaine » Thu Mar 06, 2014 8:15 am

I had the two regs for years, just thought it was to much of a dead head fuel and hurting my black holley pump. Im running E85 with a #8 fuel line all the way to the regulator. then I used two #8 fuel hose from the reg to the carb. I have a small alum filter in it. A long time ago with one reg it was running out of fuel near the finish line. So I went to two and it was fine. Im running a 1050 dom.

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Re: bad cam?

#14 Post by John_Heard » Thu Mar 06, 2014 8:54 am

Gotcha, didn't realize it was E85 which would take more volume. A fuel pressure gauge would be helpful for sure just to help rule that issue out. If it was running out of fuel, it should really lay over hard vs just wanting to not rev further. I'm thinking more ignition, wires, plugs, or springs.

What's the game plan? When you going out next?

Have you went through the ignition system? Cap/Rotor, ohmed wires, etc?

novacaine
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Re: bad cam?

#15 Post by novacaine » Thu Mar 06, 2014 9:13 am

I went thru the MSD box a couple yrs ago and had the 6AL refurb and bought a 6ALN and replaced. wire was one last season and the plugs are new. Springs are one season old . I have only made 6 total passes on the engine. 4 on the 10.1 compression and then 2 on the 13.1 set up. First pass was 6.84. and sick the 2nd pass was 6.69 but it tried a little to open up but just couldnt do it. The funny thing is it picked up on the 60 and 330 but the same 99 mph.

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