What is the largest cubed sbc you know of running tpi, and what kind of power does it make? Details on the combo appreciated, of course. Thanks, Oldtimer.

 

I have a mild 412ci's in my 92 Z28, dunno who has bigger, havent dyno'd it but it can hold its own

330817 block with, JE custom forged pistons 4.155"bore
eagle 4340 6" H-Beam rods, 4340 stroker eagle crank 3.800"stroke,
splayed billet main caps, 292XFI retrofit rollor cam,
comp ProMagnum 1.6 Rollor Rockers, ARP hardware, hv pump,
Alum AFR 195 Competition port heads 74cc and 9:1 compression, 30# SVO Injectors,
custom chip, MSD 6A, Holley Stealth Ram, Holley 58mm TB, March Alum under pulleys.
SLP Ceramic Coated 1 3/4" Headers, dual high flow Magnaflow cat's into a Dynomax Ultra 3" cats back,
Imco High Flow muffler with twin 4" Tubes sticking out the back.
BMR tubular K-member, BMR tubular A-Arms, BMR Extreme TQ arm,
TDS Wonderbar, Spohn Front and Rear Sway bar kit, Spohn sub frame connectors with BMR Boxed lower control arms and
Spohn LCA brackets, BMR Driveshaft safty loop.


and my 91 4x4 has a 421ci LTR sbc Speed Density TPI going into it, but its not runnnig yet, awaiting the custom pistons from JE still

 

Paul Pfatt Racing used to build large displacement TPIs back in the 80s. They built the following 454 small block and compared an extrude honed stock base w/AS&M Semi-Siamesed runners to the Lingenfelter SuperRam using the same extrude honed base as well as a Holley 750 carb on a single-plane intake. It used a set of large volume ported Bow-tie Phase VI heads (which I doubt flowed over 280cfm), solid roller 256/266 - .596/.582, uncapped 1 ¾” dyno headers. The small cross-sectional area of the extrude honed TPI base hurt the power on both long/longer runner TPI systems,, but didn’t do all that bad considering the average power from 2500 – 5500rpm. Too bad they didn’t test one of the old Air Flow Sensors TPI intakes (now know as FIRST Injections) - with its larger cross-sectional area and higher flowing base,,,, it would have really shined on this type combination.

RPM –- AS&M – SuperRam – 750 4-bbl
2500 - 242/511 - 232/489 --- 233/489
3000 - 317/556 - 312/546 --- 292/512
3500 - 355/533 - 350/526 --- 327/490
4000 - 436/572 - 429/564 --- 427/561
4500 - 489/571 - 505/589 --- 500/584
5000 - 503/528 - 527/554 --- 535/562
5500 - 500/478 - 519/496 --- 554/529
6000 ----------- 483/425 --- 550/482

Average power from 2500 – 5500
AS&M – 406/536
SuperRam – 411/538
750 4-bbl – 410/532 (427/526 from 2500 – 6000)

 

GM high tech performance did a write up on project Magnum TPI. It was a 396cid super ram motor. when bottom 12s and made 33xhp at the wheels.

 

double post..