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Discussion Starter #1
porting a TPI or get a better intake!

read this carefully
the best results I got when useing a TRUE TPI were with a ported EDELBROCK base, PORTED and siamesed SLP runners and a ported plenum, siameseing the base lost tq , yes its possiable to raise the rpm level the engine runs at by siameseing the base but the cars not quicker,the SUPER RAM and CUSTOM STEALTH RAM both out flow and out perform the ported TPI, the SUPER RAM flows about 245cfm untouched the STEATH RAM flows about 275cfm untouched both can be improved about 25cfm with port work. the standard or ported TPI is designed to work best in about the 1000-4000rpm range, with cams in the 205-220 @.050 range, the super ram in the 2000rpm-5500rpm range with cams in the 210-225 @.050 range and the stealth ram in the 4000-6500rpm range with cams in the [email protected] range
http://www.eecis.udel.edu/~davis/z28/buildup/plenum/
http://www.geocities.com/softtailduece01/
http://www.eecis.udel.edu/~davis/z28/winter01/dyno/dyno021105/webpage021105.html

you really need a cam upgrade and at least minimal head porting or aftermarket heads to take full advantage of the higher flow rates the super ram and stealth ram provide, rear gear changes to gears in the 3.73-4.11 range help keep your engine in the higher rpm ranges where the aftermarket intakes can provide thier full benefit
<b> engines are a system, REQUIREING ALL PARTS MATCH THE INTENDED RPM RANGE AND AIR FLOW LEVELS FOR BEST PERFORMMANCE, if you keep the idea that an engine combo is only as strong as the weakest link firmly in mind youll have a better combo! THE STOCK TPI intake is extremely restrictive, almost any mods help. BUT keep in mind chevy designed that TPI intake for the under 4000rpm range where your car spends 80% of its time ,not as an intake for max HP,you can get large gains in hp with a change of parts to match the 4000-6500rpm range but you will loose some low rpm tq in the trade for much higher hp </b>

heres a few things to read
http://www.idavette.net/hib/camcon.htm

http://victorylibrary.com/mopar/cam-tech-c.htm

http://www.69mustang.com/hp_torque.htm

http://www.ryanscarpage.50megs.com/combos1.html

notice all the better hp engines are running better flowing heads and cams with 225 plus duration

the formula for HP is (tq x rpm /5252=hp)
so if your stock TPI makes 330ft lbs at 3800rpm that equals 238hp
but add 50 ft lbs of tq due to better airflow and/or larger displacement and design the engine and gearing to run at 4800rpm and youll have
380ft lbs x 4800rpm/5252=347hp thats over a hundred hp increase!

BTW EMAIL me if you want more info on the custom stealthram I use on my 383
 

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Official Forklift Driver
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Re: porting a TPI or get a better intake!

grumpyvette said:
the best results I got when useing a TRUE TPI were with a ported EDELBROCK base, PORTED and siamesed SLP runners and a ported plenum, siameseing the base lost tq ,
You did siamese the Edelbrock base and lost tq and overall power was better un-siamesed?

Did you dyno that set-up, and if you did, where did the tq and hp peak at?

More good info, Thanks! :thumbsup:
 

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DC Crew
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Re: Re: porting a TPI or get a better intake!

Great info! Once we get our "facts" page up, I'll get this info on it.
 
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