Large Vortec bowtie, Engine?

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F-BIRD'88
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Re: Large Vortec bowtie, Engine?

Post by F-BIRD'88 »

U seem to want to talk about it rather than do the obvious and low cost stuff too.
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Re: Large Vortec bowtie, Engine?

Post by 6.50camaro »

Fel Pro 1003 can be found for under $35 each or if you unshroud the valves and open the chambers up the .024 steel shim gaskets are under $15 each from Speedway motors . Most of their own line off gaskets are ok and cost a lot less than name brand stuff. Dan
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Re: Large Vortec bowtie, Engine?

Post by F-BIRD'88 »

Use the felpro 1094 steel shim gasket (..015" …)
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Re: Large Vortec bowtie, Engine?

Post by 88bluestar »

What's your take on possibly running 1.3 roller rockers on the exhaust? Would it help build cylinder pressure, and increase torque. 1 3/4 primary headers, open exhaust
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Re: Large Vortec bowtie, Engine?

Post by CGT »

88bluestar wrote: Thu Oct 04, 2018 1:21 am What's your take on possibly running 1.3 roller rockers on the exhaust? Would it help build cylinder pressure, and increase torque. 1 3/4 primary headers, open exhaust
If you look on my "Special Needs" thread, I did a little testing with 1.3 rockers on the exhaust of it. It was kind of interesting
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Re: Large Vortec bowtie, Engine?

Post by GARY C »

CGT wrote: Thu Oct 04, 2018 9:06 am
88bluestar wrote: Thu Oct 04, 2018 1:21 am What's your take on possibly running 1.3 roller rockers on the exhaust? Would it help build cylinder pressure, and increase torque. 1 3/4 primary headers, open exhaust
If you look on my "Special Needs" thread, I did a little testing with 1.3 rockers on the exhaust of it. It was kind of interesting
CGT, do you think that would still be the case with a shorter ex duration?
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THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
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Re: Large Vortec bowtie, Engine?

Post by CGT »

GARY C wrote: Thu Oct 04, 2018 10:52 am
CGT wrote: Thu Oct 04, 2018 9:06 am
88bluestar wrote: Thu Oct 04, 2018 1:21 amWhat's your take on possibly running 1.3 roller rockers on the exhaust? Would it help build cylinder pressure, and increase torque. 1 3/4 primary headers, open exhaust
If you look on my "Special Needs" thread, I did a little testing with 1.3 rockers on the exhaust of it. It was kind of interesting
CGT, do you think that would still be the case with a shorter ex duration?
Maybe, maybe not. I guess it really depends on which one of the things that the different ratio changes, caused the power gain/loss. Did it like less peak lift, less area, or did it maybe just like coming off the seat slower....hard to say.
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Re: Large Vortec bowtie, Engine?

Post by 88bluestar »

Maybe i read the wrong post but couldnt find the info on running the 1.3 rockers.
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Re: Large Vortec bowtie, Engine?

Post by GARY C »

CGT wrote: Thu Oct 04, 2018 11:09 am
GARY C wrote: Thu Oct 04, 2018 10:52 am
CGT wrote: Thu Oct 04, 2018 9:06 amIf you look on my "Special Needs" thread, I did a little testing with 1.3 rockers on the exhaust of it. It was kind of interesting
CGT, do you think that would still be the case with a shorter ex duration?
Maybe, maybe not. I guess it really depends on which one of the things that the different ratio changes, caused the power gain/loss. Did it like less peak lift, less area, or did it maybe just like coming off the seat slower....hard to say.
It will be interesting to see what development comes from the ex side over the next 10 years, although most will probably keep it under their hat for a while.
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THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
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Re: Large Vortec bowtie, Engine?

Post by CGT »

88bluestar wrote: Thu Oct 04, 2018 3:30 pm Maybe i read the wrong post but couldnt find the info on running the 1.3 rockers.
Maybe I didn't post that. I don't feel like sifting through it all to find it. :D Do you have Excel?
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Re: Large Vortec bowtie, Engine?

Post by levisnteeshirt »

Tuner wrote: Sat Sep 15, 2018 2:08 pm
zums wrote: Sat Sep 15, 2018 11:42 am
Tuner wrote: Sat Sep 15, 2018 11:02 am

^^THIS^^ :D You all who think this head is too big, too tapered, too big a bowl or too this-or-that, too whatever it is you are criticizing, most likely have not actually run them to know from experience what you are going on about. OP, if you do change to a different head, don't be too quick to get rid of these because you could be throwing the baby out with the bathwater.
Yea, sure, thats obvious by the op's first post, maybe the self proclaimed carb experts should stick to carbs
Tom
Have you actually run these heads? There could be several reasons the OP's engine is down on grunt coming off the corner. Perhaps you haven't noticed, there is more to tuning than just the carb. Ignition timing and the advance curve has more to do with tuning than the carb, because, basically, gasoline burns. In particular, these heads are unique because they need less spark advance than most people think and they are particularly allergic to too much timing at and below the torque peak. The timing that makes best power is too much to make best torque and low end grunt below the torque peak. A locked distributor or "all in at 2500" makes an exactly backwards advance curve because the electronic ignition's slew rate timing retard causes too much advance at low RPM when the timing is right for best power at high RPM.
=D> ,, they wonder why the crate car I worked on could drop down at will and pass other cars with much higher budgets ,, wasn't the only thing I did , but locked advance isn't always the ticket
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Re: Large Vortec bowtie, Engine?

Post by levisnteeshirt »

Tuner wrote: Wed Sep 19, 2018 11:12 am Anyone who has actually run these heads has no comment about the OP saying he used 36 degrees spark advance with this head which GM identifies as "Fast Burn" and advises 28 ~ 32 in the instructions they supply with the part?
Eh ,, 604s with some laps like 36 ,, despite what anyone else says , or it's what the one I messed with liked,, e85 def need 36
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