sufficient bottom end for procharger?

[got6spd?]

Is there anybody running a scat 9000 crank with a procharger.

I can get a great deal on a carb setup p-1sc and I'm debating whether I should get it or not.

My engine is a 383 with:

TRW forged pistons
scat rods
scat 9000 cast steel crank

I know that I'm going to need to go to a dished piston but do you think the crank and rods will hold up? I'm shooting for around 630 horse around 6200rpm. What do you guys think.

[go-fish]

Scat rates the safe MAX HP for the 9000 at 600. Personally, if I were shooting for your gaol, and I have, I would save up for a forged rotating assembly and your new cam as well. I'm pretty sure you aren't running over a 110* LSA on an N/A motor, right?
I recently built a Mopar 408 D1-SC'ed engine. K1 forged crank/rods, Diamond forged slugs, 114* Lobe Sep Angle, and a pump gas friendly 8.5:1 CR.
1st dyno session it detonated on it's way to making 650 HP/607 lb ft. Timing was hot and the water injection wasn't on so it hammerd the mains.
Tore it down, crank almost made it out OK but was turned minimally. The pistons initially looked like they were toast but one quick wipe with a rag and they looked shiney and new still. Forged stuff is awesome!!!New bearings and one main cap later the the timing was reduced and we made 584HP and the exact same torque number. I am happy with it being below 600 anyway, it'll last longer and let my Tremec last a little longer as long as I don't hook.

Moral of my story? Forged stuff and Superchargers should by synonymous with eachother. Replace your parts, get a wide LSA cam and set the timing right and you will be in buisiness. The keys to supercharger success is Cam selection, Compression Ratio, components strength/selection.

Also, what exactly are you talking about "a carb setup p-1sc", a blow through carb/P1-SC together?

[got6spd?]

As far as the cam goes I can return the one I got for any other grind, that's not an issue. No, I just meant that it's setup for a blowthrough carb, sorry.

thanks for the reply

[Turbo67camaro]

Don't forget top end upgrades -

Valve springs have to work harder to close the valves under boost, so don't forget to upgrade those, or the valves may start floating at high rpm. Heavier duty pushrods and roller rockers are a very good idea also.

[got6spd?]

Is the only week link in my combo the crank, it's the only thing that isn't forged?

Also, do you think I could get away with using my exhisting forged trw pistons and basic forged scat rods?

I wouldn't mind getting a new 4340 scat crank and then rebalancing the assembly.

[DeltaT]

If you don't spin it faster than maybe 6200-6300 and you set it up so it never detonates, that crank should be fine, IMO. RPM is tough on a motor but detonation is way worse. I think you could hit about 600rwhp with a P1SC and a good breathing 383, then you'll start running out of blower, IMO.

I could only get 7.2# out of a Vortech S-trim on my 383, so I had to go up to a T-trim to get to 12#. Now she's putting out 632rwhp last check.

Jim

My Site: http://home.mindspring.com/~jim_fisk/id1.html

[got6spd?]

sorry but which crank are you talking about, using the exhisting scat 9000 or the forged one?

shoot I'd be happy with 500 rwhp!

[go-fish]

Actually, I think you will be fine with the cast crank and the power you're going to get from the P1-SC, if you stave off detonation.
You can throw a P1-SC on any engine and you aren't going to have too much supercharger.
Depending on your current comp. ration and design of your pistons you may be able to machine your pistons or get a tad thicker head gasket if it's allowable but a P1-SC in my guestimation would be good with up to 10:1 compression.
If you have closed chamber heads you are a step ahead of the detonation.
If this is all for the most economical route, you can live with the cast crank. You may need to find less CR if you are over 10:1 CR. Looks like a cam swap is just about the biggest deal. P1's are little bitty guys and you can stick'em on just about anything. Get the cam specs right, you don't need to go as big on a NA engine.
As for heads, this is a big limit on HP. If you have a set of good heads you should be in business, if you don't then you just won't make as much HP as a nice set. As said by Delta T though, having puney hardware could get you into trouble. You don't need to go get Hi-$ valvetrain but hi-performance is a must. A valvetrain for any hi-revving engine will suffice.
I think the 600 HP estimation is pretty on target for an excellent 383. I think 14.7psi one atmosphere and makes an engine 100% efficient, doubling HP. The 7 psi you will get out of the tiny P1-SC will net you 50% efficiency taking a 400 HP 383 to 600 HP.
So how much HP you make now? add 50% and that is where you could be with a P1 and the right cam and CR.
It may sound like I swapped opinions about you needing a forged crank but you would be right on the line of whether you need one or not. I think you could get away with because I think the 630 hp is un attainable with an "average" 383 and P1-Sc.
You will want to get a carb from a reputable shop that specializes in blow through designs. My dyno guy said my carb from http://www.customcarbs.com/ needed no tuning, out of the box, on the engine,650HP. Good all the way through the range and simulated real world throttle pulls.

[DeltaT]

The cast 9000.

Jim

[got6spd?]

my current combo is:

200cc aluminum pro topline heads
ferrea hi-perf valves
comp springs, I believe 931 (which ever ones go with a xr292s cam)
comp solid rollers
harland sharp rockers
comp pushrods
750 double pumper (I was going to have custom carb go through it)

Currently I'm at 10.2:1 with my trw's but I found some srp's that will bring me down to 8.8:1. The cam swap is no big deal, my supplier will trade me for whatever grind I want. As for horsepower I'm assuming around 515hp with the higher compression and bigger cam, 470 with the lower compression setup.

I was probably going to run a msd btm box, is that sufficient enough to avoid detonation, provided that the timing is set right?

Also, is it a good idea to run a air/fuel ratio gauge on a sc motor?

[got6spd?]

oh yeah, thanks for all the replies, I appreciate it

[DeltaT]

8.8:1 is too low for a small blower like the P1SC. I would aim for about 9.5:1 with that blower, so it will be snappy off boost, and reasonably safe with the aluminum heads.

8.8:1 would be OK if you plan to upgrade to the F1 blower sometime, but then you really would need to change your crank.

AFR gauge, connected to a wideband O2 controller like the ones from Innovative or FJO Racing, are a great way to go. Skip the narrowband O2 sensor setups - they are obsolete. Bonus: Get one that datalogs to a laptop. It allows you to test and tune yourself. It will pay for itself very quickly.

BTM is a nice box and will get you there.

Jim

[go-fish]

I purchased my 6 AL box and was going to buy the part to retard timing, THEN I ran across the 6AL box with the built in BTM. Now I wish I would've found someone like Delta T to fill me in on all this stuff.
Research; lesson learned.

Is it possible for you mill any surface off the piston and use a taller head gasket? I don't think you'll build enough boost to start blowing head gaskets.

[got6spd?]

maybe, how much material can you mill off of a piston and how do you know how many cc's were milled? The pistons are already somewhat dished so I don't see milling them helping much.

Also, what kind of head gaskets do you guys run on these setups? There are some SCE gaskets that are 0.093 which would bring compression to right around 9.2:1. Seems a little odd though running that thick of a gasket.

[got6spd?]

have any of you ever pushed these basic scat rods with 3/8 bolts hard? I'm not sure if they can handle the power.

[got6spd?]

have any of you ever pushed these basic scat rods with 3/8 bolts hard? I'm not sure if they can handle the power.

[got6spd?]

one more thing, how much harder is it to cool one of these engines compared to a naturally aspirated engine?

[DeltaT]

Don't the Scat rods have nice ARP capscrews in them? Again, it's mostly rpm that kills rods and rodbolts, not high cylinder pressures.

As for cooling, it's not that much harder to cool them considering how much time a sane person can actually spend in hi-boost ;) Road racing is toughest on the cooling system, so if you plan to do it, overbuild your system. I went with a big Griffin dual 1.5" core radiator and Evans coolant on mine, with separate oil and tranny coolers. Now when it's below 60, I have to keep a thermostat in there to prevent overcooling.

Jim

[got6spd?]

no, these only have 3/8
arp through bolts

[Gtrpunk23]

My dad is a distributor for scat and he likes to keep his status up with them so we get good prices when we get our own stuff. So any time anyone needs stuff we get it for them at whatever it costs him. He gets real good prices if you want/need anything pm me or call him at work 201-489-7770 and he'll gladly check a price out for you. It's time to order my stuff too so I'll be making an order with them soon anyway.
Lemme know
Chris