turbo or supercharger?

  • Thread starter Thread starter Anonymous
  • Start date Start date
A

Anonymous

Guest
i have a t-5. seems there is an issue with a manual transmission and a turbo?
 
No, there are no issues with a manual trans and a turbo.

What have you been hearing?
It's actually easier than an auto because you don't have a vacuum modulator line to mess with.
 
The only "issue" is that you cannot load the turbo prior to launch with a clutch the way you can with a torque converter and trans brake. This is somewhat offset by the lower HP losses in a manual tranny. Unless you're building a dedicated drag car it is not really an issue at all.
 
StrangeRanger":2gun9hkx said:
The only "issue" is that you cannot load the turbo prior to launch with a clutch the way you can with a torque converter and trans brake.

The way to solve that problem is with a MSD "two-step", which allows two different rev limiter settings.

The lower RPM setting (usually around 3000-3500) is engaged on the starting line. Even the the thottle is wide open, the RPM are limted by the MSD. Since the throttle is indeed wide open, and all the air and fuel flow is along with it, this makes possible for the the engine to build boost on the line in neutral.

Of course, there's a whole lot of popping and banging out the exhaust, because the MSD limits RPM by cutting spark, but once the light goes green you'll be running on all six again and off to killer run (if you have traction)
 
Yep,and all that popping and banging means that the rev limiter is cutting spark to cylinders to keep the revs down,and all that air and fuel is going right out the exhaust and into the turbo where it is ignited by the fire from the cylinders that are still firing. Burning lots of fuel/air in the manifold and turbo really spools it up,and that equals BOOST!
I think I need a turbo....every time I post about the subject I start feeling all funny........... :wink:

Terry
 
I thought I had read somewhere that it was actually bad to have a car backfire because it can damage the blades of the turbo... but I knew thats how you build boost... and I KNOW it works as Ive put the 3k pill in my msd and it built boost. can you get the turbo to fully spool like that orrr? I know I could get my ihi to spool to 7 psi on the line with my auto brake torquing which happened to be fully spooled, but with a larger turbo could you do the same with the auto?
 
Linc's 200":24rd0yju said:
The way to solve that problem is with a MSD "two-step", which allows two different rev limiter settings.

Of course, there's a whole lot of popping and banging out the exhaust, because the MSD limits RPM by cutting spark, but once the light goes green you'll be running on all six again and off to killer run (if you have traction)

The MSD unit will kill cylinders in a ramdom manner. that is why al the poping and banging Do the ones they sell now still do this? There are rev limiters that do not do this. Crane Ignition units don't do this. However thier catalog units that they came up with around 1991 will not work on a 6 cyl.
They can make one to order though that will work on a six. (at least they did back then).
 
hasa68mustang":2h9wmajg said:
1) I thought I had read somewhere that it was actually bad to have a car backfire because it can damage the blades of the turbo... but I knew thats how you build boost

2) but with a larger turbo could you do the same with the auto?

1) You might be thinking of a backfire through the compressor....yes, that can actually loosen the compressor wheel from the shaft or bend blades. A big bang through the exhaust just makes it spin faster!

2) Not really when in gear unless you have a very loose converter.
Of course, if you have a transbrake, that WILL build boost on the line

80broncoman":2h9wmajg said:
1) The MSD unit will kill cylinders in a ramdom manner. that is why all the poping and banging Do the ones they sell now still do this?

2) There are rev limiters that do not do this. Crane Ignition units don't do this.

3) However thier catalog units that they came up with around 1991 will not work on a 6 cyl.

1) The design hasn't changed. Anytime you drop plug fire to control revs, you will get popping and banging.

2) Show me one.
It's the ONLY way an ignition box can control revs.
Again, anytime you drop plug fire to control revs, you will get popping and banging. Now, EFI will drop injectors. THAT IS DIFFERENT.

3) I don't think it makes any difference. Logic would say it does, since you have to change the selector inside of a tachometer to either 4, 6 or 8 cyls. How does a MSD know what RPM the engine is running at??

A 3000 RPM chip in a box programmed for 8 should drop plugs at 4500 RPM on a six and 6000 on a 4 cyl...I guess? I have never hit the rev limiter.....
 
what if i only reved the car (using a tach) to about 3500-4500rpm before launch and no higher?
that would work just long as i dont rev that high?
 
asimmons04":22c65ry9 said:
what if i only reved the car (using a tach) to about 3500-4500rpm before launch and no higher?
that would work just long as i dont rev that high?

that may build you boost (only a little bit at that) for a second tops, then the engine isnt really under a load. the engine must have some sort of load on it for the turbo to make boost.

you can only do that with the ways linc and others mentioned, which would be brake boosting with an auto or a 2 step revlimiter.
 
asimmons04":12ku3yog said:
what if i only reved the car (using a tach) to about 3500-4500rpm before launch and no higher?
that would work just long as i dont rev that high?

If that is the best way to launch your car effectively....then that works.

Building boost before a launch is only good IF you have GREAT tires (like slicks) on a great surface AND the rest of the suspension is up to snuff.

If you launch at too high an RPM on the street, you will just spin your tires. If you are at the strip and you launch hard but the car bogs and then picks up again (like mine) then it would help a LOT to be able to build boost before you leave the line. For me to fix my lauch needs either a transbrake or rear brakes that will hold the slicks from spinning on the line.
 
What about a switch that engauges while you depress your clutch that cuts out timing while on the starting line to build boost?
What if you tied a momentary switch to your, say safety start switch at the clutch and used the white wire off the DSII to retard timing to help build boost at the start line? Would it work, I'm thinking poor redneck white-trash here.
And when you are shifting while running down the line, I don't think it would make that much of a difference when engaging the clutch because you would be in and out of it very quickly. Not enough time to really throw the timing out, but if it did wouldn't it keep your boost up while inbetween shifts, maybe?

Kirk
 
kirkallen143":pu5t44ct said:
1) What if you used the white wire off the DSII to retard timing to help build boost at the start line?

2) And when you are shifting while running down the line, I don't think it would make that much of a difference when engaging the clutch because you would be in and out of it very quickly.

2) I use a MSD box to make fire, not the DS II box...but it IS an idea!

2) A latching relay work allow it to work on the line only. Simple.
 
it just occured to me...

since i already break loose and roast the tires when i take off after revving (all motor) it may be a good idea to launch with my low first gear with no boost and let the motor build the boost after launch. otherwise i'll just sit and spin.

i guess that would make sense. now to find a turbo? lol
 
asimmons04":1eog8his said:
i guess that would make sense. now to find a turbo? lol

or get some tires and suspension stuff... cause if it gets up like my car with the turbo it would break the skinny tires loose at any speed in 1st and it being an automatice it worked out to be 50 mph was 5000 rpms in 1st gear...
 
Link, MSD knows how mainy cylinders it is working with, (if installed correctly), this is done by clipping wires on the outside of the box,
 
Linc's 200":3kk0n7tq said:
fast64ranchero":3kk0n7tq said:
this is done by clipping wires on the outside of the box,

Mine has no external wire to clip

mine does, it has 3 wire loops and I had to cut on of them to make the revlimiter start at the correct rpm...

it took me awhile to figure out why I couldnt get it to do anything at 6000 rpms, when the 5500 rpm pill was in it.... then I read the instructions again.
 
well i have the largest widest tires i could fit on my poor 14" factory wheels.

theyre wide (compared to stock) but arnent THAT wide. they grab good but with that super low 1st in my T5 it really puts down the torque :)

so now i suppose the question is supercharge it or turbo it?

maybe like, pros and cons?
 
Turbo of course! But I'm biased.

Superchargers take more power to turn.
Generally speaking....
If you took any given motor and put it on a dyno and added a supercharger, did a pull, removed the SC and installed a turbo, and did another pull, the turbo would make more power given the same boost levels.

The cons of the turbo is the exhaust plumbing.

Will
 
Back
Top