Winter build Stock CID project

[tpepmeie]

Originally Posted by efnfast

At 15% loss, I calculate to 530. That's 93 per liter. I'm not sure I'd want more cams and still have to drive it on the street.

Originally Posted by Paul Workman

Pete said at one point in his motor's development that he was putting 474 HP to the wheels. Since then he has tweaked it a little more, he said.

Using the same math, that would tickle 557+ @ the crank

You guys know what I think about converting rwhp on a dynojet to brake horsepower on an Engine dyno...

[efnfast]

Originally Posted by tpepmeie

You guys know what I think about converting rwhp on a dynojet to brake horsepower on an Engine dyno...

Sure Todd, but that's all most of us can do. -Steve

[tpepmeie]

427 LT5 build 1 observations

• 1/19/2011: SF901 Engine Dyno, 300 rpm/sec, SAE1349 correction - 669 bhp [703 using STP correction]
• 8/9/2012: Dynojet shop "A", SAE1349 correction - 637.2 rwhp
• 5/10/2013: Dynojet shop "A", SAE1349 correction - 638.2 rwhp
• 5/10/2013: Dynojet shop "B", SAE1349 correction - 634.1 rwhp

I realize this is but one like-for-like comparison, but three different chassis dyno tests, across two days and two shops, and nearly 1 year apart. the variance is 4 hp.

The same engine, on the superflow engine dyno, at the same atmospheric correction, was only 30-35 hp higher. Maybe that engine dyno is a bit stingy? However, using the internet accepted 15% driveline loss, that engine should have made close to 750 brake horsepower on the engine dyno. Unlikely.

I've tested a couple others on that engine dyno, but unfortunately haven't done a chassis dyno on those. Not my engines, so not so easy to do the comparison testing.

Sorry, didn't mean to get off topic. I'm expecting a solid 550-560 brake hp out of this cammed 350 cid project.

[Top Toy]

Engine dyno numbers don't make good comparison points, either, because you're no longer using using the in car accessories (IAF housing, exhaust, cooling, drivetrain et al). The only valid comparison is SAE on the same day and same chassis dyno. Should also be based on area under the curve to account for the full range of operation, not just a one point spike or engine tuned for peak HP only. Anyone up for a shoot out? [emoji6]

Sent from my HTC U11 using Tapatalk

[Hog]

This will be an awesome project Todd, looking forward to t. I would think that your stock cube LT5 will have a little extra noise from the rectangular cam lobes you'll be using (j/k)

I made a splinter thread in case anyone wants to discuss the virtues of the various methods of measuring engine output.
http://www.zr1.net/forum/showthread....527#post274527

[tpepmeie]

And she’s done. Sad to see it go, but there’s a race to make!

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