Large Tube runners.
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From: Budd Lake New Jersey
Large Tube runners.
SO I have a set of AS&M runners 42mm I think and Im goin to replace my stock(ported ones soon). Need to know, will these work with the stock TPI base or should i get the Edelbrock TPI base? Are these huge gains? I have searched on a few websites headr positive things I'm just not familiar with these runners
Le Mans Master
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From: Australia
Max G’s
Joined: Nov 2008
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From: Monroe OH
NCM Sinkhole Donor
The large tube runners will improve your power as well as move your power band up a little. Now obviously the higher flow intake manifold with the large tubes will give an even larger gain, but if you can or only want to do the runners at this time, they are worth it. 
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Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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It's not really a black and white question. There are some intakes where you could lose a bit of your low-mid range while gaining lots of HP. OTOH, with larger longtubes, you'll be gaining everywhere from idle on up.
Just not THAT much.
With tubes alone, I'm thinking the avg gain is about 15hp. That's up top. But, you'll also feel a bit more umph in lower rpms.
With tubes and aftermarket base, the gains jump to the 25hp range. I think the common feedback is 2-2.5 seconds with this modification.
FWIW, the TPI shootout comparison used a honed stock back with various tube changes. Because I didn't think there was THAT much material to remove from the stock base, I always believed the tubes were more important.
Then I heard more and more about the FIRST setup. It's base is the one with much better transitions into the heads. So, as far as large-tube bases go, I'm not terribly impressed with them. But, I would consider tubes if that's all ya got to run.
Just not THAT much.
With tubes alone, I'm thinking the avg gain is about 15hp. That's up top. But, you'll also feel a bit more umph in lower rpms.
With tubes and aftermarket base, the gains jump to the 25hp range. I think the common feedback is 2-2.5 seconds with this modification.
FWIW, the TPI shootout comparison used a honed stock back with various tube changes. Because I didn't think there was THAT much material to remove from the stock base, I always believed the tubes were more important.
Then I heard more and more about the FIRST setup. It's base is the one with much better transitions into the heads. So, as far as large-tube bases go, I'm not terribly impressed with them. But, I would consider tubes if that's all ya got to run.
Le Mans Master
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From: Australia
Race Director
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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Injector bung dungs.
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Le Mans Master
Joined: Aug 2007
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From: WV
This is the setup Im currently running on my 383 stroker motor. Edelbrock base, Accel runners , and a Mega ported plenum from "Corvette Plenums". I really can't say how much better it is then stock, because I installed it on the motor when the motor was new.. I can however tell you that I can rev this motor about 400 rpms higher then the stock motor could go with the stock intake.. Im sure a Super ram or a Mini ram would be much better but I wanted to retain the stock look..I also reamed the tubes out a bit ( more to clean them up) and enlarged the base a small amount.. Remember, this is on a 383 with a mild cam and bigger heads, so on a stock motor there should be a more noticeable improvement..The stock base will work, but there will be a gain with the Edelbrock base...
...WW
...WW
Last edited by WW7; Feb 4, 2012 at 07:17 AM.
Le Mans Master
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From: Australia
in the 1/4 with no other changes
Revised tune got another .10
12.7 w/ TPI - 12.2 w/ HSR
Race Director
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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You might not be impressed over the change vs the value of the runners. In fact, at some point you might decide to put (cheaper to obtain) OEM units back on and selling the increasingly rare large tubes.
Thread Starter
Advanced
Joined: Nov 2011
Posts: 99
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From: Budd Lake New Jersey
This is the setup Im currently running on my 383 stroker motor. Edelbrock base, Accel runners , and a Mega ported plenum from "Corvette Plenums". I really can't say how much better it is then stock, because I installed it on the motor when the motor was new.. I can however tell you that I can rev this motor about 400 rpms higher then the stock motor could go with the stock intake.. Im sure a Super ram or a Mini ram would be much better but I wanted to retain the stock look..I also reamed the tubes out a bit ( more to clean them up) and enlarged the base a small amount.. Remember, this is on a 383 with a mild cam and bigger heads, so on a stock motor there should be a more noticeable improvement..The stock base will work, but there will be a gain with the Edelbrock base......WW
...WW
Le Mans Master
Joined: Aug 2007
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From: WV
Once everything is apart the injectors are fairly easy. When putting them back in be sure to get new O-rings for the injectors and for the fuel rails, if the ones in there are original they are pretty old.. When putting the injectors back in be sure to lube the O-rings with Vasaline to make them go in without rolling over and causing a leak..Also I found the best way is to put them in the fuel rail first , then line them up and push them into the intake manifold holes..Be sure to hook up the fuel lines and test for leaks before installing the runners and plenum..Nothing worse then assembling everything, then finding out you have a leak.....WW
Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
The 1 in siamese and putting a shine on the first in or so of the runner (that C.P. does) entry will do 0 for you except drain your wallet; sorry, its the truth
You want to get a good 3 out of that wall then seriously port the entire runner end to end all the way through;gotta really dig into the casting some
Base, too otherwise just bolt it all together and run it.
You want to get a good 3 out of that wall then seriously port the entire runner end to end all the way through;gotta really dig into the casting some
Base, too otherwise just bolt it all together and run it.
