stealthram info

[grumpyvette]

Here's some flow figures, right off the manufactures sites in many cases. Keep in mind the concept of the chains weakest link. It does ABSOLUTELY no good to match a base or runners on a TPI intake that flows 250cfm if the other part flows 200cfm. You'll still only flow 200cfm. The HOLLEY STEALTH RAM FLOWS at 275cfm out of the box, and can easily reach 300cfm with minor port work. The stock TPI has a hard time flowing 230cfm even with minor port work. Look here. Most of this info is right off the Accel, Holley, Edelbrock, and TPIS sites. Add a little math and the results become much clearer!!!

Intake......runner length .... port in...... out
Stock GM Base----- 6.375"------------- 1.47"------- 1.96x1.20
TPIS base------------6.125"------------- 1.75"------- 2.09x1.28
Accel base-----------6.125"------------- 1.75"---------2.09x1.28
Holley base--------- 6.000" ------------ 2.30”-------- 1.90x1.23 (2.337 sq inches)

Runners
Stock TPI-------- 7.250"------1.470" round(1.70 sq inches)
SLP -------------- 6.625"------1.600" round (2.01 sq inches)
Accel LTR------- 6.625"------1.615" round (2.05 sq inches)
TPiS-------------- 7.625"------1.660" round (2.168 sq inches)
Mini ram --------3.500”
stock MRII with 1204 (AFR 195) ports, 58MM - 265 cfm
stock MRII with 1206 (AFR 220) ports, 58MM - 281 cfm
MRII clean-up, 1206 ports, 58MM - 292 cfm
MRII cut, weld, port, etc, 58MM - 321 cfm
LT1 ----------3.000”

Runners (measured individually)
Stock........................................................................................................................................203.17 cfm
ACCEL.....................................................................................................................................242.02 cfm
Extrude/ACCEL........................................................................................................................275.83 cfm
Super Ram................................................................................................................................289.18 cfm
Intake manifold with 3/8 inch radiused inlet .............................................................................222.45 cfm
Holley stealth ram ………..........................................................................................................275.00 cfm


Stock intake manifold with runner
Stock.........................................................................................................................................198.72 cfm
ACCEL......................................................................................................................................213.52 cfm
Extrude/ACCEL.........................................................................................................................217.11 cfm
Super Ram.................................................................................................................................220.67 cfm
Holley stealth ram ….................................................................................................................275.00 cfm
ACCEL Hi-Flow intake manifold with 3/8 inch radiused inlet.....................................................251.51 cfm
ACCEL Hi-Flow intake manifold with runner Stock...................................................................215.83 cfm
ACCEL......................................................................................................................................232.53 cfm
Extrude/ACCEL.........................................................................................................................243.21 cfm
Super Ram.................................................................................................................................240.24 cfm
Extrude-Honed ACCEL Hi-Flow intake manifold with 3/8 inch radiused inlet.............................275.83 cfm
Extrude-Honed ACCEL Hi-Flow intake manifold with ACCEL runner.......................................266.94 cfm
Edelbrock Performer RPM manifold (Stock)...............................................................................286.51 cfm
Edelbrock Victor Jr....................................................................................................................275.24 cfm


Runner Length


Stock TPI manifold ...................8” ...............runners 11.25”............... cylinder head 6”.............total 25.25”
Accel super ram manifold........ 8”................runners 7.00”............... cylinder head 6”............ total 21.00”
Holley stealth ram manifold .....6.26” ................................................. cylinder head 6”............ total 12.26”
Edelbrock performer RPM ...........................runners 6.00”................ cylinder head 6”............ total 12.00”
Edelbrock Victor Jr .......................................runners 5.50”................ cylinder head 6”............ total 11.50”




Now playing with the figure in the calculators below, what you'll find is that if your using a 350 size engine as a guide, the tpi runner length is ideal for peak tq 3427rpm and 2700-4000rpm for peak hp.

The Accel Super Ram is ideal for peak tq at 4032rpm and 3300rpm-4800rpm for peak hp.

Holley's Stealth Ram runner length is ideal at 4700 for peak tq and 5618rpm to 6282rpm for peak hp.

The TPIS Mini Ram and LT1 intakes are ideal for peak tq at about 5200rpm and 7244rpm to 8101rpm for peak hp.

By hp peak, in the above lists, I'M REFERRING TO THE RPM RANGE WHERE combination of cross sectional area MATCHED TO THE plenum to INTAKE valve distance WHERE THE internal AIRFLOW HARMONICS TEND TO INCREASE THE CYLINDER FILLING EFFICIENCY (WHERE THE INTAKE WILL TEND TO PULL THE MOST HP). Now KEEP FIRMLY IN MIND the engines tend to enter valve float and get close to engine red line by 6300-6700rpm depending on your combo. After running all the available combos, I've found a HOLLEY STEALTH RAM has been EXTREMELY EFFECTIVE on several engines tested. CURRENTLY THE STEALTH RAM SEEMS TO
BE THE CHOICE, ESPECIALLY IF MATCHED TO GOOD CYLINDER HEADS AND THE CORRECT
CAM.




The intake ports on the STEALTHRAM as it comes from HOLLEY. It fits the Felpro #1205 gasket port size. That's a perfect match to the AFR 190cc heads. This is a 1206 gasket and while its easily possible to port it to fit , it
does not leave any room for mistakes.

I know of 3 people now using the stealth ram on larger port heads. All needed to have a machine shop weld a little extra metal to the upper port area and do minor machine work to allow the ports to be ported out to those larger ports sizes. But all three guys reported excellent results and power. Personally I advise you just go with the AFR 190cc heads and avoid the problem as they flow enough to make over 500hp if the rest of the engine like the compression and cam is designed to use the stealth rams high air flow rate. But, you can make it work with the larger heads ports with the help of a good machine shop. BTW those 1206 port size fits many of the larger 210cc-220cc heads available.

 

[grumpyvette]

viewtopic.php?f=55&t=431

http://www.holley.com/91604211.asp

stealthram base

more info

below is a picture I took about 9 years ago, a very early proto type version on my test mule corvette 383 engine where I was testing cams with versions of the custom intake during research.

btw, if your using a stealth ram it requires a small base distributor for clearance
if your replacing a TPI intake with a tunnel ram, HOLLEY STEALTH RAM or other intake requiring a small base diam. distributor, a gen 1 sbc distributor that fits physically, into the intake can be used in most cases, it can be made to function, most guys use aftermarket remote coil distributors, but the small diam. camaro distributor works,I used a HOLLEY 890-160 distributor

Stealth ram /msd 6A /Holley # 890-160 distributor
Ignition wireing

MSD 6A
First Two wire connector
Small orange----------coil positive
Small black------------coil negative

Magnetic pickup (NOT USED)

Single Heavy red----------battery positive +

Single Heavy black------- battery NEGATIVE/GROUND

Second Two wire connector
Small white---------small white from two pin plug on holley 890-160 AND splice in small tan Chevy tach pick-up from harness
Small red------------small red on Holley two pin plug and splice in heavy pink from Chevy harness



HOLLEY 890-160 distributor
FOUR PIN PLUG
Smaller Four pin plug on distributor plugs to ( Holley #534-138 adapter* ) then large plug on adapter plugs to larger 4 pin factory harness

HOLLEY 890-160 distributor
TWO PIN PLUG
(see MSD CONNECTION INFO ABOVE)

*these adapters are very easy to make from salvage yard parts(wire plug connectors)

not related here,but think things through
but some other point,s, that are often over looked,
especially if youve upgraded to a higher compression ratio,
350,383, or 400 based sbc engine in your third gen,
is that if you swap a significantly better flowing intake,
like the Holley stealth-ram,
on too what would other wise be basically a stock TPI engine the
stock O.E.M, exhaust is very restrictive
the STOCK CYLINDER HEADS are VERY flow restricted
The stock cam is limited to about 4700 rpm \
the stock valve train is far less than ideal
the stock injectors are not able too feed a significant boost in power
the stock HEI, *even a small cap aftermarket version, may need mods to work,
most O.E.M ignition wire is pathetic.

if youve upgraded the cam, you may require a higher stall speed converter