For a 355 motor, does anyone know of any articles, comparisons, anything about this "package" by Edelbrock:

58mm TPI Throttle Body Part # : 3804
Hi-Flow TPI Runners Part # : 3865
TPI Base Plate Part # : 3860
Aluminum Center Bolt TPI Heads Part # : 60859

I'm starting to think that I'm the only person in the country that's bought this "complete package". I can't find any info on what these parts will do together, how much they flow, what they're supposed to make in terms of power, or ANYTHING!!! Maybe I'm not looking in the right places. It would be nice to know how these parts compare to the MiniRam, Stealth Ram, LT1, or even similar TPI components sold by SLP, AZ Speed & Marine, etc.

Does anyone out there know where I can get this info????? Is it even out there???

 

Tests done on a hot 383 but intake to intake performance differences still relative
http://www.compcams.com/Community/Ar...?ID=1737510521

 

Edelbrock seems proud of their parts, but they aren't much of an upgrade over stock.

 

hi i have a 1988 iroc with a hyd roller 96-2000 vortec engine its a tpi set up with a tpis big mouth intake along with slp runner and a matching ported plenuem to go with it, 52mm throttle body i recently bought a gm cam that was used on their ram jet 350 with this be a good match with what i got also the heads are the oem that cam with the iroc (cast iron) with steel roller tip rockers 1.5 - 3/8
Cam Specs:
Description- Hydraulic Roller Design
Advertised Duration- 288(Int) / 308(Exh)
Duration @ .050"- 196(Int) / 206(Exh)
Max Valve Lift W/ 1.5 Ratio Rocker- .431(Int) / .451(Exh)
Lobe Centerline- 109

 

WOW! Fantastic article. So the Edelbrock base and runners - if properly ported should get me a substantial amount of power. I think that Az Speed & Marine offers a service where I can send them the components and they'll port them to where they need to be - but I'm concerned that if I ported out the base plate I'd also have to port out the heads - which I don't want to mess with. I've already gotten the 58mm TB ported to the Plenum, just not the plenum to the runners.

I posted my problem on the tech board, but just for background, I'm making 343lb/ft of torque at the wheels at 3500 RPM, but only 243hp at the wheels at 4000 RPM before it flattens out and drops! My crower cam is a 213/221 @ .050 with .506/.525 of gross lift so I'm trying to figure out where the bottleneck is.

So what do you guys think of me just porting out the plenum to match the runners and maybe opening up the runners a bit? What do you guys recomend that I do? Will it just be cheaper to throw away the Edelbrock stuff and get the TPIS or AZ Speed & Marine stuff while keeping the Edelbrock heads? Is there nothing I can do with the Edelbrock runners and baseplate to make it match the performance of the other brands?

In retrospect, I shouldn't have gotten any Edelbrock components and gone straight with either TPIS or AZ Speed & Marine with AFR heads, but now I'm stuck and need to make the best of it. Any ideas???

 

I think you have to compare how much extruded honing your existing parts will cost versus new. A new base and large tube runners from TPIS will run around $850. From the intake comparisons it looks like an extruded honed system matches performance of TPIS system. Remember too that they are testing a 383 engine which requires more air than your 355 especially as rpm increases. Bottlenecks with stock TPI are small runner diameter and poor flowing base. If extruded honing is cheaper ($500), I think you would be good with that for your 355.

At flywheel you are probably making 290hp at 390ftbls which isn't too bad. Here is flow data I found for them on page 7 http://racingfeed.com/downloads/chevy_flow_data.pdf

Flow
lift, int, ex, e/i %
0.1", 64, 54, 84.4%
0.2", 122, 96, 78.7%
0.3", 177, 124, 70.0%
0.4", 217, 147, 67.7%
0.5", 229, 166, 72.5%
0.6", 232, 175, 75.4%

They seem like decent heads. Maybe you can have some port work done for a few hundred? Have you read this post about TPI flow? https://www.thirdgen.org/forums/tpi/...owing-tpi.html

 

Check the graphs in the intake article.
All the TPI based intakes do that because they can't flow enough air to run up top which is typical of long tube runner intakes.
For performance (and cost) you would be better off with a HSR that would run past 6K if you have the heads and cam to support it