I, and a few others, have seen 40 hp difference on 700hp engines....482-496 cubic inch FE's.treyrags wrote: ↑Wed Jul 11, 2018 3:27 pmThank you for speaking in terms of %. It wears me out to see people quote "X" horsepower gains or losses like it doesn't matter what the engine displacement or horsepower range is involved. I recently built and dynoed an aluminum block (Ford Racing) small block. It's a middle of the road street engine that made 1.4 per inch. I used the same exact combination as the previous build except for the block. It was down 1%. I'm not sure the dyno is even that repeatable lol. After 13 pulls the exhaust ports were gray and bone dry. The breathers were also dry. BSFC .39 - .45. I respect Larry and Darin's findings and believe them completely and their findings are probably true in many cases, especially as you approach 2 hp/ci and up.But you can't paint everything with a broad brush.Headguy wrote: ↑Wed Jul 11, 2018 12:37 amI haven't had that problem, I have built hundreds of aluminum engines. And had a few back to back te sts. The most I lost was about 1.5 %.statsystems wrote: ↑Tue Jul 10, 2018 11:07 pm
Even that won't help. You have people who are professional argument makers. You can post your real world experience, backed up by professional people no less that Larry Meaux and Darin Morgan and they still want to tell you how stupid you are because so and so runs his car on a dirt bull ring with a stupid weight limit blah blah blah. Or how an inline 4 can be compared to a V-8 that has had its architecture blown out beyond what any engineer ever had in mind when designing it.
I mean really...can any thinking, intelligent man not see the folly in such thinking? Let's take a liter 4 cylinder, and increase its bore, stroke and RPM increased in an equal amount to what the standard American V-8 has been and THEN tell me how good the aluminum is.
Not one of us has said aluminum doesn't have a place in engine blocks. If you are under 1000 HP and N/A and if your stupid rules don't allow flyweight shit the cast iron will beat it every time.
I had a customer back in 1998 with a dragster. I begged him not to buy an aluminum block for his car. He figured weight was better than HP. It wasn't. Since it was a rear engine car, he had to add weight to the car to get it to hook and he gave up power.
He stepped on his own dick. The car never performed like he thought it would, but did exactly what I told him it would. A couple seasons later he parked the car.
Exhaust ports were dry on my engines as well. You don't have to have greasy exhaust ports to have cylinder distortion or blow-by.
That's just my experiences.