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asshole81

Registered User
Can I take normal 3.8 v6 fuel injection and run it with my super charger when the compression ratio 8.2.1 S.C. to 9.0.1 Fuel injected and if so how long would it last...................NEED HELP NOW.....JUST REBUILT TOP END AND BOTTOM END WENT IN DRIVE WAY,DID NOT EVEN GOT A ROAD TEST
 
Someone already answered you.

You can do it, but it won't last. The compression ratio will be too large and you will likely blow a head gasket, but if you are really unlikely you will break the crankshaft.

The SC crankshaft is forged and very strong. N/A birds are not.

If you must do it, swap the NA V6 complete and leave the SC off.
 
I really think that there isn’t a problem with the crank in the NA V6, Buick V6’s have a cast crank and they do just fine even with the funky offset rod journals (same as the ford 3.8’s). The compression ratio isn’t too high to run under boost it is only a half a point higher than the late model SC engine, with aluminum heads that shouldn’t be a problem. If the NA V6 can’t handle 250 Hp even with a blower I would be surprised. Many people ask this question, but the answer is always the same, You’ll blow it up. Has anyone ever done this? Does anyone know for sure? I don’t think anyone has, or does.

Jeff
 
On the SC, it's not only the extra loading on the crank from the boost, as in the case of the Buick, but also that extra belt trying to rip the snout of the crank off when you're hammering it !!


cheers
Ed Nicholson
SCCoO
 
I am no expert with the Supercoupe, although I have just rebuilt my engine and am running fine with it. I do have a lot of experience with turbo, diesel and N/A performance engines.

The forged crank and pistons are mainly a protection issue in case of detonation. If the engine is set up right, safe from detonation and over heating, cast crank and pistons will survive just fine. The problem is that if you wish to squeak the last bit of performance out of it you walk perilously close to that safe line. Step over it for just a few seconds with cast gear and something will break, whereas forged may survive for another day.

I have seen turbo engines survive with stock N/A longblocks. It is usually detonation that kills headgaskets as well. I have no doubt that a stock V6 longblock would survive supercharging if it was used moderately. If you pushed it for top speeds and quarter mile times you would likely soon learn its limitations.

Steve Best
 
I still don’t see it as a problem. There are many manufactures that make supercharger kits for the NA V6 birds and Mustangs, most are not roots style. But they still take power to turn and place added stress on the snout. Again I don’t think it’s a problem for stock SC #’s or a little better. I seriously doubt he wants to make 600HP, and if he does it’s a waste of money to do it with this or the SC engine.

Jeff
 
There is a huge difference between a roots POSITIVE DISPLACEMENT blower and a centrifigal blower like a turbo or paxton.

The dynamics in this engine are a lot different than a turbo. Yes a NA engine might last if you don't push it hard. Try getting hard into boost down low and you will kill something.

Aaron
 
It doesn’t make any difference what, where, or when the boost takes place, as long as the engine is kept away from detonation it will do fine especially down low in the RPM range. The pistons are hyperutectic (sp) in both engines, so they would probably be the first to go in either engine. The load on the crank snout goes up as boost and RPM are increased it doesn’t matter what type of supercharger is used. Granted a roots is the least efficient of all types of forced induction, therefore it takes more power to turn this type than a Paxton, Powerdyne, Vortech or what ever. Like I said before if he is looking to run around with 300 or less HP then IT DOESN”T MATTER.

Jeff
 
Well, if it seems your gonna do it regardless, and I am quite interested in seeing if in fact it will last.

I say do it and let the rest of us know how it goes.
 
Oh, so now everyone has an opinion.

Whatever the reason, a Naturally Aspirated 3.8 is not going to last, long term, if used instead of a SC block. Primary failure points will be pistons and the crankshaft.

I've seen messages here posted of crankshafts breaking even in our cars.
 
help

I would like to thnx all of you guys for your help on this subject it seems like everyone has vaild points but the reason why i ask'd is in the FORD shop guide the motors are the same for crank- cams-heads-pistons and messurement are bang on, the only differents is the 8.2.1 SC vs 9.0.1 NA.....so I would like to thnx you all for taking the time out for my question, so i guess what this come downs to is that if it has tits or wheels it cost you huge money..... Thnx Kyle
 
Kyle, the measurements may be the same, but if you check the part numbers, everything is different. The block, the crank, the rods and pistons, and cylinder heads are all different from a N/A 3.8 to the SC motor. For example, if you look at the main caps on a regular 3.8 block, they're just normal size like a typical North American V-type engine. But on the SC motor, they're BLOODY HUGE to support the pounding of the boost and the SC belt pulling on the front of the crank.

A decent used SC motor can be had for a reasonable price, so what you're proposing to do doesn't really make sense in that respect.

cheers
Ed Nicholson
SCCoO
 
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