Engine Guru's, Explanation needed???
#1
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Car: '89 Formula 350 & '86 Z28
Engine: L98 & 355ci
Transmission: 700r4 in both
Engine Guru's, Explanation needed???
Im getting ready to build my 406, and I always read CHP. I knew I could find a few proven buildups that would best suit me. While in my search I found two buildups that I really liked, but when I compared them side by side the results AMAZED me.
The 406 with smaller heads, less compression, smaller cam(hydraulic flat tappet vs. Mechanical roller even), and dual plane air gap destroyed the "on paper" way more powerful 406.
The "bigger" 406 has almost a full point of comression, Higher flowing heads, bigger cam(not too much bigger, roller), Victor jr.
They both used Headman 1 5/8" headman headers and a 750 Holley. Can anyone try to help me out here, because this goes against everything we are taught! the 406 ci makes the 210s not too big, but the 180s a little undersized. Sure the 180s should make a little more low end, but the 210s and slightly bigger cam should shine above 5000RPM, but they dont.
Here are the links to the articles: Smaller, more HP/TQ , and Bigger, less HP/TQ
I have made a HP/TQ graph comparing the two to maybe save a little time. Am I missing something here?
The 406 with smaller heads, less compression, smaller cam(hydraulic flat tappet vs. Mechanical roller even), and dual plane air gap destroyed the "on paper" way more powerful 406.
The "bigger" 406 has almost a full point of comression, Higher flowing heads, bigger cam(not too much bigger, roller), Victor jr.
They both used Headman 1 5/8" headman headers and a 750 Holley. Can anyone try to help me out here, because this goes against everything we are taught! the 406 ci makes the 210s not too big, but the 180s a little undersized. Sure the 180s should make a little more low end, but the 210s and slightly bigger cam should shine above 5000RPM, but they dont.
Here are the links to the articles: Smaller, more HP/TQ , and Bigger, less HP/TQ
I have made a HP/TQ graph comparing the two to maybe save a little time. Am I missing something here?
#2
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Car: 4
Engine: 6
Transmission: 5
They both used Headman 1 5/8" headman headers
The test would look very different with properly sized headers.
#3
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first , don,t believe everything you read, some engine tests are deliberately tuned and altered to make a certain manufacturers parts look good or to prove a point by deliberately mis-matching parts. a few minor changes would make that larger cammed and port engine produce much better power
EXAMPLE
RPM Torque H.P.
4000-509-378
4500-536-459
5000-523-497
5500-500-526
6000-463-528
6500-447-553
7000 - 349-465
554HP
406ci
AFR 210cc Competition Package
10.1
750 Carburator
MSD Distributor @ 36° Timing
Lunati Hyd. Roller Cams 242°-252°
.560-.572 lift 112 Lobe Centers
1 7/8" Hedman Headers
93 Octane Pump Gas
This package is available from Ceralli Competition Engines
look these over
http://www.diabolicalperformance.com/diabolical406.html
http://www.carcraft.com/techarticles/68999/
http://www.wpedirect.com/sportsmanengine.htm
http://www.speedomotive.com/newpage6.htm
http://www.rlpengines.com/chev-406.htm
http://enginenick.50megs.com/81chevette.htm
http://www.camaros.net/racing/SBCombo.html
http://chevyhiperformance.com/techarticles/90719/
http://www.chevyhiperformance.com/fe...ehicles/67318/
EXAMPLE
RPM Torque H.P.
4000-509-378
4500-536-459
5000-523-497
5500-500-526
6000-463-528
6500-447-553
7000 - 349-465
554HP
406ci
AFR 210cc Competition Package
10.1
750 Carburator
MSD Distributor @ 36° Timing
Lunati Hyd. Roller Cams 242°-252°
.560-.572 lift 112 Lobe Centers
1 7/8" Hedman Headers
93 Octane Pump Gas
This package is available from Ceralli Competition Engines
look these over
http://www.diabolicalperformance.com/diabolical406.html
http://www.carcraft.com/techarticles/68999/
http://www.wpedirect.com/sportsmanengine.htm
http://www.speedomotive.com/newpage6.htm
http://www.rlpengines.com/chev-406.htm
http://enginenick.50megs.com/81chevette.htm
http://www.camaros.net/racing/SBCombo.html
http://chevyhiperformance.com/techarticles/90719/
http://www.chevyhiperformance.com/fe...ehicles/67318/
#4
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Car: '89 Formula 350 & '86 Z28
Engine: L98 & 355ci
Transmission: 700r4 in both
Thanks guys, I was all FUBAR. I couldnt process it, lol. I was trying to think of what the heck was going on.
#5
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Location: San Antonio, TX
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Part of the reason is the headers. The other is that the roller cam is no bigger than the hydraulic yet it has bigger heads and a single plane intake. The restriction is with the cam/headers not the heads/intake.
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