Ground Pounder Street 470

[Old Man Mopar]

Thank you for the roller lifter info.

 

[Spun Bearing]

where in okie land are you?

Black City area but probably moving to Phoenix soon.

 

[qkcuda]

The E street heads are the same as the RPM, the only difference is the valve seat material. Its more for street driving rather than racing. No big deal. I have used about 5-6 sets without any issues.

Solid rollers last just fine on the street with our lifters. I designed them to run on the street as well as the race track. I have never had to rebuild a set of our lifters. I had a customer send a set back for inspection after an entire season of short track sprint racing. Everything still looks good as new after 1200 race laps and 700# spring pressure.

Dont know anything about the ProComp rockers, never used them.

I ordered a set of the E Street 75cc heads. I just got looking at Summit's website and there is a Note "Designed for use with hydraulic flat tappet camshafts. The valve and seat combination is not recommended to be used with a hydraulic roller camshaft" This note was not on the Edelbrock website.

Of course, I do have a comp 236/242 541/544 hydraulic roller cam. I use comp 26120 beehive springs which are 155 on the seat and 377 at .600 lift. I assume your spring package is probably stiffer. Do I need to worry about the seats? This engine is for street use and occasional drag racing and will also not see much over 5500 rpm.

 

[txstang84]

I'm kinda interested to hear the expanded version of that answer too, but despite my lack of familiarity with those products, I'd guess Edelbrock makes that distinction as a general advisement not to expect the powdered metal style seats to last as long or take the same abuse as the hardened ductile seats in the RPM heads. The valves are also supposedly a little heavier than their RPM counterparts, according to Edelbrock. FWIW, most domestic new mfr engines these days use powdered metal connecting rods, and as long as they're not abused*, they last just fine.

 

[qkcuda]

Turns out the E Street heads were backordered. I took it as an opportunity to rethink things, and changed my order to the RPM's. I don't want to worry about the valves and seats if I'm beating on it. I also went from the 75 cc heads back to the 84 cc heads, since it would have put the dynamic compression into the questionable zone for pump gas.

 

[Challenger340]

Great Looking Engine & Dyno Numbers !! Good Job !

I'm really interested in your Lifters here ?
Up to what Valve Spring Rate ? / at what Installed Seat Pressure ?, do you recommend for your Solid Roller Lifters on the Street ?
I need to run some Cam/Spring Slew Rate Sims.

For comparison, we get similar horsepower numbers(575 hp) using an Flat Tappet Solid Cam...on the Ported Edelbrock rpm's....on the smaller stroke(less Torque) 451 pump gas packages we sell, using the CompCams XS282S(244* / 252*) .
It Certainly can't match the Bigger Stroke or Roller Cam for Torque, only 583 ft/lbs, but we just find it a cheaper route to go without the costs of Offset Crank Grind, and the Roller Cam/Hardware/Springs, etc., Costs ?

For a 660hp and 640 Ft/Lb Pump Gas level pkg., we just default to the 493 RB Package(we also offer it on a lowdeck W/2.200" journals), still with a cheaper Solid Flat Tappet Cam & Hardware, but with the INDY EZ Heads on a 6hr "prep for service" including a CNC Chamber plunge cut to 80-82cc's, once again to keep costs down.

This 451 one is 6 years old now.... been to California & back twice now from Alberta Canada, 45,000 Miles still going strong, mid 11's at the track in a B-Body.

The 2nd Dyno Sheet is the 493 Low, or High Deck 91 Octane Pump Gas Package, very popular with the Brackets Guys these days at 664hp and 644 Ft/lbs Torque on a Cheapo low maintenance Flat Tappet Solid Cam.