Race motor

[DriftFiat]

the nitrous was another option im not going to run a turbo and nitrous. Nitrous has been used in drifting a driver named Ken Gushi used nitrous on his scion drift car for a while. I have some track time in my 240sx but i still need toget the fiat out on the track. If i use nitrous can i tap the intake manifold and spray it directly? And how do you o-ring a throttle plate?

[Europa]

Nitrous has been used in drifting a driver named Ken Gushi used nitrous on his scion drift car for a while.

Scion drift car? Aren't Scion's FWD? Did someone modify a FWD to RWD for drifting? OR, is it that the Scion body was grafted to some other floor pan/frame? I am curious.

[Zmatt]

Just a thought, but it may be easier for you to get the power you want if you swap something else in. A Toyota 4AG is about the same size, and the 20v version would have more than enough power. The Miata engine is also a good choice and it turbos well.

[DriftFiat]

It is a scion drift team car so they have deep enough pockets to convert it to rear wheel drive. And as for the 4-age i thought about that plus you can mount weber side drafts on it . I just love carbs i wonder how hard fabrication would be?
Heres a cool vid of a carbed 20v http://www.youtube.com/watch?v=D4q7-xwkQUU but does anyone think that the roll cage having bars connected to the front struts will help the body not fold under the load? Sorry for asking so many questions ive got alot to do and not much time to do it.

[Zmatt]

The 4ag came to mind because i have a buddy who races an AE86 and it's a killer engine. Lot's of support, cheap, easy to work on and high rev limit. you could grab a Mk3 supra rear end, an AE86 5 speed and a 20v and have an awesome setup. It would be expensive though.

[DriftFiat]

prolly cheaper than trying to get this engine to that level.

[DriftFiat]

prolly cheaper than trying to get this engine to that level.

[DriftFiat]

Sorry for that double post^ i hate slow computers Any way the motors coming out today and nows the time to decide if im going to swap or build this one. Ive got a Garrett T3 turbo from a turboed volvo and a flange that i made today that i could use to make a downpipe. So I think im going turbo but i have one problen where do i get forged rods and pistons if im building this motor its going to run at least 10psi. Does anyone know who does good engine machining in my area? i want to get my crank knife-edged and the whole rotating assembly balanced. I also want to the chevy rod bearing mod has anyone done this with good results i didnt see anyone talk about it on turbo124.

Thanks again
Austin Leiphart

[maytag]

i want to get my crank knife-edged
Austin Leiphart

... why? .....

[DriftFiat]

less rotating mass = more power to wheels less resistance on motor and better throttle response.

[pastaroni34]

Does anyone know who does good engine machining in my area? i want to get my crank knife-edged and the whole rotating assembly balanced.

This is the kind of work I specialize in.. I don't know any other shops that knife edge cranks, it really is quite a bit of work. Plenty of them balance though. To be honest I think your money is better spent in a new turbo.

As for the pistons/rods.. you'll be fine with stock parts up to about 18psi, then you'll want better pistons. That is assuming you have a decent tune and you're not detonating, then all rules go out the window. Rods are plenty strong to take the power. RPM is what kills rods, if you're planning to live above 7000rpm then you'll want them, and a different flywheel. There are a number of companies that offer both rods and pistons, just about every builder has their own favorite brand. When it comes to rods, I've found that you get what you pay for.. also remember that your rod bolts are just as important as the rods themselves.

[maytag]

less rotating mass = more power to wheels less resistance on motor and better throttle response.

I think somebody's been foolin' with ya.

Knife-edging cranks is an old 'trick' that old-timers used to do before they knew how to measure if it worked or not... they thought the physics seemed right, and plus it sounds cool, right? "Knife-edged".... sounds all mad-max, don't it?

But in fact your rotating mass will be dictated by the weight of your reciprocating mass. You don't want to just go willy-nilly shaving weight off the crank's counter-weights. Once you've gotten as much weight off the rod / piston assembly as possible, then you will see no difference (I mean that; ZERO difference) between a balanced crank that is knife-edged, or one that is drilled / plugged in the proper, traditional method. Plus, that knife-edge takes a LOT of time, which costs money, and leaves you with a crank that is hard to do anything with later, should your bob-weight change for any reason. (try to find a machine-shop that will "rebalance" a knife-edged crank )

And if you are among those who believe that the knife-edge "cuts-through the oil in the sump better", windage has been addressed very successfully with crank-scrapers, which are not difficult to build (much easier than say, knife-edging a crank), and in fact knife-edged cranks have actually been shown (in some cases) to create turbulence, rather than reduce it. The laws of aerodynamics will tell you that a knife-edge is NOT an aerodynamic shape. And in severe duty, very-high RPM situations, knife-edge cranks have been known to break because of the harmonics that are at play, that did not exist in a properly balanced crank.

As a previous poster said: your time and money could be MUCH better spent on something else, like a turbo, or maybe one of these:
http://www.soundracer.se/

Or if you just want to do it because one of your buddies said to, then spiderjim can make you a very, very pretty emblem that you can attach to the car that says "Knife-edged".... probably cheaper than actual knife-edging.

[pastaroni34]

One cannot make such sweeping generalizations about crankshaft lightening or knife edging.

I can speak from direct experience on Fiat motors, it makes a difference.

As for windage, I have no way to test this so I cannot speak to its effects.

As for balance, Fiat 4 cylinders are a single plane crankshaft with the throws 180 degrees opposed. They are inherently balanced as long as the reciprocating masses (rods, pistons, pins, clips, rings) are equal.

Regarding strength, you'll find the Fiat DOHC crankshafts are very well made, especially for its time. It is true that harmonics can kill crankshafts but I have never heard of this on a Fiat crankshaft, lightened or not. This is likely due to the crankshaft's forged construction and short overall length. Notice that it never required a harmonic balancer either.

[maytag]

Jason:
no arguments here about lightening the crank. I am speaking quite specifically about knife-edging, not lightening / balancing in general.

Are you saying that you DO see a performance increase in a knife-edged crank, over a traditionally-lightened crank?
If so, Where do you see this improvement? How has it been measured? Has it been compared in back-to-back comparisons with a blunt-edged (but similarly lightened / balanced) crank?

I ask, because I respect your work, your knowledge and your opinion. My experience is admittedly NOT fiat-centered. And if there are differences that affect this, and which make the Fiat TC respond differently than other motors to this sort of modification, I'd love to understand it.

thanks!

[pastaroni34]

My comparison was between an OEM part and a lightened one. The lightening profile was what most seem to consider "knife edging" I do not think a blunt or sharp edge makes a considerable difference. I have seen some OEM crankshafts on other cars that have angled rather than blunt edges.. who knows!