B&M supercharger (Page 4/6)
Patrick OCT 05, 03:52 AM

quote
Originally posted by Coolkoolpyle:

If your still interested in hearing more I'll continue with valvetrain tomorrow.




For sure! ...and thanks for the quick lesson on supercharger vs turbo.
klork OCT 07, 10:14 AM
Wait a minute. Your telling me that a roots supercharger is more efficient then a turbocharger? And that turbos dont hold up to abuse? You have got to be kidding me. Every big rig going down the road has had turbos on them for decades and they last for hundreds of thousands of miles under far more abuse then that little b and m blow and more then an old school detroit diesel blower. The old 2 stroke diesels needed a blower to get air into the cylinder. They didnt really create much in the way of boost at all. They had sloppy clearances and were not under much stress. Volvo has been running turbochargers as an option on every model of car since the early 80s and they have no problem going a couple hundred thousand miles on a factory turbo. Ford was big into turbos in the 80s with the turbo 2.3 and those turbos are very reliable once they started doing the water cooled turbos around 1983 and they put out at least double the boost of most factory supercharged vehicles. Ford uses turbos on virtually every model now along with Audi, BMW, Honda and many others No manufacture would be using turbos in this day and age if they needed to be replaced at 100k miles. And your trying to tell me Japan only makes cars to last 60k? Who has had some of the longest lasting cars on the road since the late 80's and especially through the 90's? Japan.

And roots superchargers are the most inefficient way of making boost. The heat up the air more then any other supercharger or turbo. Twin screw is a way better design and makes low end boost just like a roots but with far less heat. There is a reason high end superchargers are not roots style anymore.
Coolkoolpyle OCT 09, 04:00 AM
Your obviously a turbo guy

Big rig turbos are 5000 or more just to rebuild for a reason

They are made of aerospace quality materials
They are regularly serviced and maintained with new parts their entire lives.

It's big business working with commercial turbos

Volvo is the least cheapskate manufacturer in the world and in stock form their turbos don't put out big boost numbers.
but do tend to live longer than most

Hence why they are used so often in performance engines.

And yes superchargers do make heat when boost levels get high

But if you think just cause someone said it in a book it's true

Yeah. I saw that claim too

So I started temping my high presser side to see how much

Not much at all

Didn't even become a real problem untill boost hit about 14lbs
and even then it wasn't so bad to require a intercooler

Then we hit 21lbs
That's when the heat really showed up
along with substantial mechanical losses driving the supercharger.

The intercooler was invented and primarily used for turbos.

Why

To manage the excessive heat.

I'm not saying they are bad
Just not practical for low boost

We are not talking ultra high rpm racing engines with 36lbs of boost burning ethanol.

On the street
It's about getting off the line

If turbos were so great at making power from the get go they would be on top fuel dragsters.

Indy cars? Hell yes
Practical

Even decent on lower power drag cars

But a street motor?

That supercharger is going to make tire smoking torque from 1500rpm up to 5000

5000...
Isn't that about the time your turbo is starting to make power?
Case its when I'm shifting.

Great for light small engine cars that don't need a lot of torque

But no one ever said they were bad

Just their not the most practical choice for a v6

I'm not building a 10,000 rpm motor

I'll make all my ponys down low and shift fast


That's what it's about on a fun street car anyways.


Not like you can drive it 150mph so you can get the rpm to hit full boost in fifth gear around town

In almost every turbo v8 I've driven there was a definite feeling like I never really got to play in the big power zone
I was speeding by the time it was really coming on and had to back off

Blowers pucker yr butt from the start and just have that fun feeling all the time

If your into turbos


Great
They are definitely fun
and often a challenge

Certainly capable of making tremendous power at high boosts

In the end

It's all about how you like your vehicle to perform and how you drive it.
cam-a-lot OCT 09, 05:54 AM
Great thread- very informative!

It would be awesome to see someone document and build a 300 HP blown 3.1 V6 for sure.... Best of luck with the build, and please document and provide pictures if you can....
Australian OCT 09, 06:52 AM
Proff used to talk about this as the fiero supercharger and it had been done but no sign of it in a decade or so. I would always say you mean 3.8 L67 and he would say no it is for camero 2.8.
Australian OCT 09, 07:00 AM

quote
Originally posted by Coolkoolpyle:

I consistently get about 8.5 lbs of boost from these superchargers on a 2.8

The entire unit sits 1/2 inch lower than the original fuel injection

My car is a Ferrari F355 replica.
It has additional clearence under the hood

The strut tower must be modified and a smaller coil over shock upgrade to make the room for the modifications to the strut tower
(already done)

Basically it needs trimmed back a few inches on the forward inside corner
Rewelded to close off the tower from the engine compartment and some extra bracing to ensure structural integrity of the tower.

Compared to the four link and full tubs I put into my SS Nova it will be a easy modification

As for the fuel injection I have mounted the holley sniper unit as a side draft and located it in roughly the same place as the original throttle body to make the original throttle linkage easy to hook up.
The 90degree upper manifold to supercharger is a easy build
With some good skills at cutting, bending and welding the hood clearence is not a problem..

With no emmisions
A free flowing exhaust
A matching camshaft
and the new holley sniper two bbl EFI I can pull about a additional 100 hp from a 2.8

Once fitted and functional
The 2.8 comes out and a iron head 3.4 will go in its place

In the rear wheel drive version I've pulled a peak hp of 276 and peak tq of 262 ft lbs. From the 3.6 with 8 lbs of boost.

Of course there are lots of details I'm leaving out

butt hey

I'm a professional engine builder

You can't expect me to give out my exact blueprint.

All my personal vehicles get a 50shot nitrous set up

Because superchargers lose some power in the heating of the air fuel charge the 50 hp kit reclaims another 10 to 15% more total power over the 50 because it acts like a super intercooler and dropped the air/fuel temperature significantly when the system is engaged.

I do not have a exact figure for the n2o as I don't dyno nitrous systems

I'm starting this build sometime in the next four weeks as I'm just finishing up a turbo charged supra and then I have a BB chevy to do for a customer.

Gotta pay the bills before I play on my toys.

I will video document the entire build and post links for those that are interested.



Thanks for post and nice work on the car.
klork OCT 09, 10:56 AM

quote
Originally posted by Coolkoolpyle:

Your obviously a turbo guy

Big rig turbos are 5000 or more just to rebuild for a reason

They are made of aerospace quality materials
They are regularly serviced and maintained with new parts their entire lives.

It's big business working with commercial turbos

Volvo is the least cheapskate manufacturer in the world and in stock form their turbos don't put out big boost numbers.
but do tend to live longer than most

Hence why they are used so often in performance engines.

And yes superchargers do make heat when boost levels get high

But if you think just cause someone said it in a book it's true

Yeah. I saw that claim too

So I started temping my high presser side to see how much

Not much at all

Didn't even become a real problem untill boost hit about 14lbs
and even then it wasn't so bad to require a intercooler

Then we hit 21lbs
That's when the heat really showed up
along with substantial mechanical losses driving the supercharger.

The intercooler was invented and primarily used for turbos.

Why

To manage the excessive heat.
Pretty much any modern high performance supercharged engine uses an intercooler too. If its not on there its because of cost

I'm not saying they are bad
Just not practical for low boost

We are not talking ultra high rpm racing engines with 36lbs of boost burning ethanol.

On the street
It's about getting off the line

If turbos were so great at making power from the get go they would be on top fuel dragsters.
Top fuel cars HAVE to use superchargers. The rules dictate that they are not allowed to use turbos. I can almost guarantee they would make more power with turbos over a supercharger.
Indy cars? Hell yes
Practical

Even decent on lower power drag cars

But a street motor?

That supercharger is going to make tire smoking torque from 1500rpm up to 5000

5000...
Isn't that about the time your turbo is starting to make power?
Case its when I'm shifting.
Have you driven a turbo car that was made after 1970? Hell even my 1986 XR4Ti with a single cam 2.3 made 20 lbs of boost by 3000 RPM on the stock old school mid 80s turbo. New turbo cars are making peak torque under 2000 RPM. The new BMW m3 makes over 400 ft lbs of torque from 1800 RPM to 5500 RPM and there are a ton of example of this.
Great for light small engine cars that don't need a lot of torque

But no one ever said they were bad

Just their not the most practical choice for a v6

I'm not building a 10,000 rpm motor

I'll make all my ponys down low and shift fast


That's what it's about on a fun street car anyways.


Not like you can drive it 150mph so you can get the rpm to hit full boost in fifth gear around town

In almost every turbo v8 I've driven there was a definite feeling like I never really got to play in the big power zone
I was speeding by the time it was really coming on and had to back off
Probably because the turbo was chosen to make big power. Your not going to have a turbo that lights off at 1500 RPM and make 2000 hp. But if you want a more modest 6-800 hp absolutly. You can get a correct sized turbo to light off at low rpm

Blowers pucker yr butt from the start and just have that fun feeling all the time

If your into turbos


Great
They are definitely fun
and often a challenge

Certainly capable of making tremendous power at high boosts

In the end

It's all about how you like your vehicle to perform and how you drive it.



I am not saying you dont know your blowers but you have some really really old conceptions on turbos.
fierosound OCT 09, 11:31 AM
We've had the turbo vs supercharger argument before...
http://www.fiero.nl/forum/Forum1/HTML/095858.html

Both, whether turbo or supercharger, increase the power enough that you still come out ahead after the "losses" of making it.
They both have their uses and place. If one were THAT superior to the other, the "other" would not exist.
At least with a supercharger, after you put MORE AIR INTO your engine, you aren't also corking it up at the exhaust end.

You don't see superchargers on many econo-boxes...
Turbo cars http://www.autobytel.com/co...k-turbo-cars-126123/
Supercharged cars http://www.autobytel.com/ca...ars-for-2015-128231/

But this is Coolkoolpyle's build thread.
I'd prefer to hear about his plans and build rather than read people arguing with him over his choice.

[This message has been edited by fierosound (edited 10-10-2020).]

Honest Don OCT 09, 12:45 PM
Looking forward to seeing it run!


Turbos aren’t in Top Fuel because the rules don’t call for them. You’re seeing a lot more use in Pro Mod and the Sportsman classes though.

FWIW, on my turbo 2.8 I can get 4psi by 2500rpm in good weather. Full boost usually by 3900-ish in first gear.
Johns 4.9 OCT 09, 01:18 PM
Hi,
I have one of those B&M blowers on my 4.5 engine in my 84 Fiero. Looking forward to your build and the information you are supplying!
Good luck,
Cheers