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Discussion Starter #1
Buddy of mine (1_bad_bird) finally decided it was time to rebuild the motor in his sc bird! I've put in quite a bit of wrench time on it so far getting the motor ready to come out! Everything is outta the way not so all we gotta do is get a cherry picker n pull 'er on out!

i'll get a list of what we're gonna do to it! or have done to it!

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Nice work! Can't wait to see how it works out.

Stephen
 

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Discussion Starter #4
Got the motor and tranny seperated. flywheel has a couple of chipped teeth on it... no biggie. gonna be trashed anyways. used aluminum cobra pumkin came in last friday with cobra half shafts... tranny will be sent off and rebuilt. motor is going to be bored i believe 30 to 40 over... my buddy dave got a quote from marc brown at advanced engine... marc said he can build us a 450hp motor for around $4,500 that 450 is just the motor, it does not include the supercharger and other goodies. supercharger will be ported... ummm not sure what else is in store for it. probably going to look into a snow meth kit like jobe has... i'm shooting for 550 to 600hp when it's all said and done. we'll see what happens.

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450hp on a 231 cubic inch engine is about 2hp per cube without boost???

holy, jesus, mary, joseph, i hope you own a bank or two. When its all said and done
your going to be at LEAST 30k in the hole.
 

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Got the motor and tranny seperated. flywheel has a couple of chipped teeth on it... no biggie. gonna be trashed anyways. used aluminum cobra pumkin came in last friday with cobra half shafts... tranny will be sent off and rebuilt. motor is going to be bored i believe 30 to 40 over... my buddy dave got a quote from marc brown at advanced engine... marc said he can build us a 450hp motor for around $4,500 that 450 is just the motor, it does not include the supercharger and other goodies. supercharger will be ported... ummm not sure what else is in store for it. probably going to look into a snow meth kit like jobe has... i'm shooting for 550 to 600hp when it's all said and done. we'll see what happens.
You are not going to get anywhere close to 450 HP normally aspirated out of that motor for $4,500...If Marc Brown told you he could, he is either a liar or doesn't know what he's talking about.

David
 

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Discussion Starter #7
You are not going to get anywhere close to 450 HP normally aspirated out of that motor for $4,500...If Marc Brown told you he could, he is either a liar or doesn't know what he's talking about.

David
Well he builds/has built motors for Monster trucks! He's got a very good reputation here and he stands by his work! if he says he can do it i believe it! We'll see what happens! i'll be putting the list of parts on here for the motor later tonight.
 

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Discussion Starter #8
Alright here's what's in store for the motor:

-Engle Rods
-MLS Gaskets
-Custom made forged crank (polished)
-Bore... 30 or 40 over
-Balanced
-Mill the heads and then port and polish
-Mill the block
-Valve job
- T-up Mains
-lumpy Cam (not sure how lumpy)
-Lifters
-Valve springs

there's way more than that but i'm not exactly sure where the rest of the list went. that's what i could find.
 

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Well he builds/has built motors for Monster trucks! He's got a very good reputation here and he stands by his work! if he says he can do it i believe it! We'll see what happens! i'll be putting the list of parts on here for the motor later tonight.
Apparently the guy doesn't know much about SC motors. If he did, he would tell you how the SC heads will never flow enough air to support that kind of power. Even when CNC ported, with welded exhaust ports, oversized valves and larger valve seats, the best flowing heads are going to be around 235 CFM intake @ .600 lift and 200 CFM exhaust @ .600 lift. There are no aftermarket heads for an SC, just reworked versions of the factory heads.

Then there's the crappy SC intake manifold....even if you could manage to get a pair of heads to flow way better than the numbers I mentioned above, the pancake sytle intake manifold, would be your next obstacle. Even when cut apart and reworked for greater plenum volume, it still kills flow going into the intake runners because of the screwed up air entry angle. A better intake manifold could be made and a couple prototypes for use with bottom discharge twin screw blowers have already been made, but it's still in development and will likely cost over $2K each.

Compression on the motor is also going to have to stay down to around 9.0:1 or it won't tolerate any ignition timing without detonation when you add the boost, unless you plan on running with race fuel all the time. That isn't enough compression/cylinder pressure to make the kind of power your expecting. So unless this guy is planning to build a motor capable of turning 9000 rpms and figure out how to get much more air in the motor, 450 HP naturally aspirated is not happening.

You can make 600 HP with an SC motor, but it's going to need a chemical power adder or forced induction to do it. Think twin screw or turbo...not an M90 based blower. The parts you listed so far, are the same stuff that most people are already using (except for a custom forged crank), and not even as good as what some of us are using. About that crank...you can either use a stock SC crank (forged), offset grind the SC forged crank for more stroke (they always break), use a 4.2 cast crank from a truck motor (what most people do), or have a billet crank custom made for about $2400. You might want to get the builder to clarify what he intends to use.

Good luck with your project.

David
 

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x2 im with david on this, i dont see how its even remotely feasible to cram more than 250hp out of a sc engine with no boost and still maintain a low enough CR to boost it?

you might want to cut your 600hp goal in half and call it done.

or you can go the easy route and turbo it then say hello to 450hp

and a lumpy cam is typically not optimum for a boosted application

and also you might want to check out sccoa.com many folks have spent thousands more
and still haven't broken the 500rwhp mark. The sc engine is a fun engine I know i have 3 sitting downstairs in my garage, but its just not that easy to make that much power.

your really asking alot out of a small engine
 

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x2 im with david on this, i dont see how its even remotely feasible to cram more than 250hp out of a sc engine with no boost and still maintain a low enough CR to boost it?

you might want to cut your 600hp goal in half and call it done.

or you can go the easy route and turbo it then say hello to 450hp

and a lumpy cam is typically not optimum for a boosted application

and also you might want to check out sccoa.com many folks have spent thousands more
and still haven't broken the 500rwhp mark. The sc engine is a fun engine I know i have 3 sitting downstairs in my garage, but its just not that easy to make that much power.

your really asking alot out of a small engine
I've gotten over 500 rwhp (aprox 535 rwhp) from a 3.8 SC motor, but it required a 100 HP shot of nitrous to do it.

David
 

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Discussion Starter #13
crank, cam and pistons are out... no metal in the oil pan! you can still see the cross-hatching on the cylinder walls. pistons kinda look like **** but everything else looks really good! like (motor has been re-worked recently) good. regardless, it's ready to be sent off!

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x2 im with david on this, i dont see how its even remotely feasible to cram more than 250hp out of a sc engine with no boost and still maintain a low enough CR to boost it?

you might want to cut your 600hp goal in half and call it done.

or you can go the easy route and turbo it then say hello to 450hp

and a lumpy cam is typically not optimum for a boosted application

and also you might want to check out sccoa.com many folks have spent thousands more
and still haven't broken the 500rwhp mark. The sc engine is a fun engine I know i have 3 sitting downstairs in my garage, but its just not that easy to make that much power.

your really asking alot out of a small engine
Update:

Chris Wise pulled 505 rwhp on Dyno Dynamics heart breaker dyno this past weekend at the SC Shootout. Combo is as follows...4.2 crank in an SC motor with T-68 turbo and 22 pounds of boost through a non locking C4. First pass it ran 10.6 @ 130 on drag radials.

David
 

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dam david thats pretty cool, im putting an mp t70 on my friends 90sc trying to make 550hp, but were stepping the game up to 30 lbs of boost :)

he has a 4.2 stroker as well
 

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holy crap! that look like a lot of work lol
 

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hey OP

blkbrd95... im an authorized retailer for bhj balancers, if your interested the SFI balancers for the 89-93 i sell for $350 + $10 for shipping anywhere in the 48 states

just let me know via PM

and also... you said in a previous post that your sending the block off?
where are you sending it? if you want a reputable machine shop that has hands on experience with the sc's and owns 5 supercoupes post back in your reply.
but honestly your best option would be to get it done locally, the cost of shipping would be outrageous.

but if you do decide to send it elsewhere thats cool as well, were pretty slammed right now so it would probably be at least a month before we could even touch it.

a couple things i'd like to point out to you, the stock valve springs are weak they only have 80lbs on the seat which is terrible for heat removal and high revs. And also our aluminum heads tear up valve guides so expect to have those replaced as well. Make sure when the machine shop decks the block and resurfaces the heads that they keep a low enough RA for mls gaskets, you have to let them know about that before hand else most shops will just set the decking machine and turn it out as quick as possible.

the arp heads studs for the chevrolet 2.8L v6 works for our 3.8s. Just order some arp head studs for an 86 chevy celebrity 2.8L of course. Save you some bucks.

make sure you use copper rtv on the mls gaskets, spray the gasket not the deck nor the head.

the mls gaskets I use are specific for a 97 ford f150 with the 4.2l v6. You'll need to drill one of the rivets out but its no biggie. The price just went down on them from felpro so most suppliers dropped there prices a couple dollars. They can be had rather easily for $46 per side.

it would be a real good idea to change out the stock crank pulley, they have weights on them that usually fall out with time. This could cause the crank to walk a tad. I can't verify that but every sc block we've dealth with had crank walk for some reason or another.

theres a ton more info i could give you but it'll take days and me recalling memory banks in my brain that i haven't accessed in a short while.

don't hesitate to pm me if you need/want any more suggestions or advice or recommendations or anything.

Michael Ponthieux
 

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the harmonic balancer does just that, it balances the rotating assembly and also dampens vibrations, thus its also known as a vibration damper.

our supercoupes are 0 neutral internal balanced thus we technically have vibration dampers, the bhj balancers (dampers) are much more durable than the original oem balancers.

When the stock balancers fail they usually do some damage, if your lucky you only have to chip out the remains of the original crank bolt out the crank. If your unlucky you have to replace the crank and or timing cover :(
 

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kool. good do to know. i though it was just another performance mod.
 
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