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Discussion Starter #1
I'm starting the process of planning an engine build. Im posting this mostly so I have a list (that I wont lose) of what I need, but also for some constructive criticism. My goal is a high compression N/A engine making power up to 6000-6500 rpms. The car will mostly see DD use but also a bunch of autocross events, and maybe a couple 1/4 mile runs. Im planning on using 4.11's in the ass.

Romeo Block bored .020 over
Probe #12396 SRS Flat top Forged pistons
Stock PI Heads (Will be upgraded at a later time)
ModMax 4.6 Forged 5140 I-Beam Rods
ARP fasteners all around


Need some recommendations for a camshaft,crankshaft, and oil pump.
 

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WOT Junkie and avid corn burner
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I suggest a stage two cam, especially if this will be seeing DD use. What kind of compression numbers will you be looking for? You might want to reconsider your head choice since you'll be more than likely using pump gas.
 

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Discussion Starter #3
11-11.5? Maybe I should look at slightly dished pistons.
 

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WOT Junkie and avid corn burner
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I know 10.5:1 is doable on pump 93. Heck, it's all doable if you take enough timing out of it and run a 180 degree t-stat. Any idea on what torque converter will you be planning to use? Intake manifold? Keep in mind, if you do plan to stick with PI heads, you'll wan't to look into fly cutting the pistons for a good piston to valve clearance. You can alleviate this issue by running Trick Flow heads due to the different intake valve location.

Waiting on GM to pipe in here, as he has spent more time looking into this sort of "high compression" setup.
 

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2800-3000 would be a good compromise between street and strip as far as stall. IMHO 3500-4000 is too much if you do mostly street driving. Torque converters are more for launching than anything. Higher stall is more fun at low speeds, but lower is better on fuel economy and trans heat. My car doesn't get good city mileage but I have a 3500 stall, but on the highway its decent because the converter locks in 3rd and OD. My mileage is around 22-24 mpg hwy and 8-10city...lol but rollin burnouts are fun, so I like my TC. :D
 

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WOT Junkie and avid corn burner
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It's possible to get at least 15 mpg in the city with a high stall torque converter. Keep your friggin' foot out of it! lol I get 13 mpg city, on E85, with a 4000 stall rpm converter. On gas, I get 17 mpg in the city.

8-10 city? Wow. I get better than that on E85! If you can't get better mileage than that, either your tune sucks or your driver mod needs to be done.

It's very streetable. I do it everyday. 2nd gear lock up helps, but isn't needed.
 

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you can ditch your power "goal" of making power up to 6500 RPMs with stock PI heads/cams. Never gonna happen unless Mother Nature suddenly increases atmospheric pressure just for you.

Unless you have $3000 burning in your pocket, just use a cast or forged crank, no need to want anything else.

Unless you're shooting for 12:1+ compression, this is gonna be "moderate" compression by today's standards. To run a "modern" high compression setup on gasoline, you need big cams to bleed off some cylinder pressure, and to run big cams it changes EVERYTHING, as in the whole mess turns into a high-RPM setup, which is the most expensive type of build you can think of.

2800-3000 would be a good compromise between street and strip as far as stall. IMHO 3500-4000 is too much if you do mostly street driving.
only if you don't have it tuned correctly and if you don't shrink the torque converter diameter.
 

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If you want higher RPM power, I suggest a set of Trick Flows in the 38cc variety. My power peaks at 5200 RPM, mostly due to my PI camshafts. It's a damn good street setup. With stage one or two cams, it'd be a pretty stout street setup.
 

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If you want higher RPM power, I suggest a set of Trick Flows in the 38cc variety. My power peaks at 5200 RPM, mostly due to my PI camshafts. It's a damn good street setup. With stage one or two cams, it'd be a pretty stout street setup.
Exactly what I mean. Even with trick flows, stock PI components still peak in the lower 5000 range. To truly get it in the mid-6000 range take it to a whole 'nother level (more like 3 levels, lol). Every 500 RPM increase you want to extend performance, you need to approx. double the co$t. Going to 6500 RPM from about 5000 RPM will take 8x the money (2³=8) to get it ALL working properly.
 

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It's possible to get at least 15 mpg in the city with a high stall torque converter. Keep your friggin' foot out of it! lol I get 13 mpg city, on E85, with a 4000 stall rpm converter. On gas, I get 17 mpg in the city.

8-10 city? Wow. I get better than that on E85! If you can't get better mileage than that, either your tune sucks or your driver mod needs to be done.

It's very streetable. I do it everyday. 2nd gear lock up helps, but isn't needed.
well my tune does need work,I'm running way rich, but I do have 60 lb injectors 9 inch 3500 stall and the sc probably doesn't help either...I dont really drive with economy in mind when I drive MY car lol
 

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Discussion Starter #15
Idk what stall that's rated at but 400 rpm above stock is a waste. especially if your shifting at 6500rpm or higher. I would look at 35-3800 stall.
Thats the marauder converter I thought it was like a 2500 stall?
 

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Mark VIII converter which is closely similar to the Marauder converter, stalls around 2400 RPM. At least, that's all mine would do before turning the tires over. The Marauder may stall slightly higher, but not by much. Just like some say, "Don't fear the gear", well "don't fear the stall RPM". The people who say it makes their cars really sluggish tend to have converters that are too big in size or are incorrectly modified. The sluggishness can be greatly lessened by going to a smaller diameter TC, like a 10" or a 9.5". Now, if more power to be supplied to a Mark VIII converter, it'd likely stall higher, around 2500 RPM. It's a good upgrade over stock, make no mistake about it.

While we're on the subject of torque converters, be sure to use an auxiliary transmission cooler, like a Hayden 679. I run mine after the tranny heat exchanger in the radiator. Some will tell you that's a terrible idea, but if you use a good quality replacement radiator and keep good coolant in it, you won't have to worry about the transmission oil and coolant mixing due to heat exchanger failure. With my 9.5", 4000 stall torque converter, the trans temp doesn't get above 170 during the fall.
 

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Discussion Starter #18
I just talked to alan at dirty dog, and he says it stalls somewhere around 2800, but it sounds like a converter in a smaller diameter is a better choice.
 

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All the better reason to pick up a 9.5" with 3500+ stall! :D
 

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Discussion Starter #20
What timing covers am I limited to? Can I use any romeo timing cover? Or do I have to stick with the cover on my car now?
 
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