the difference between our motor and a stroked motor

scfix92

Registered User
I have a few questions about the differences between the 4.3 stroker and the normal 3.8 that we have in our sc's. I think we have had this conversation before but I have more questions. I want to build up my sc's bottom end, and I want at least 450 hp and 500 ftlbs of torque if not more what my question is if you were to bore the heck out of the cylinder but not but left the stroke alone could still get more horsepower and high rpms. With this configuration you could still use the same forged crank and buy better rods and pistons. also has anyone offered a forged crank for the 4.3 stroker yet I am really into that but I want to have all forged internals. with a stroker kit in our engines wouldnt that create more compression I thought on our cars the goal was to lower the compression so we could make more boost. Honestly what all would I have to do for an engine internal wise to make 450 hp would I really have to go with a troked engine. I also have learned in school that in a stroked engine once it starts to wear there is a good chance of the pistongetting side ways when it comes down since it is on a smaller rod. please give me your thoughts and concerns on this topic.
 
The compression is all about piston choice. You can up the compression a little bit, and then throw boost on it, but you have to have a good tune and always use high octane fuel. If you go over 9.0:1 compression you will really need race fuel if you cap 15 psi of boost.
 
Scott Long said:
The compression is all about piston choice. You can up the compression a little bit, and then throw boost on it, but you have to have a good tune and always use high octane fuel. If you go over 9.0:1 compression you will really need race fuel if you cap 15 psi of boost.

If you up the compression like that you would get more horsepower but have a better chance of blowing even stage 2 heads right
 
No matter how you cut it, 400+hp from our engines is a tall order and will require a lot of money. When you say you want that kind of power, do you have any idea what it is like to drive a car with that kind of power? It is easy to toss around numbers, but having driven a 400+rwhp SC I can tell you that you just can't use that kind of power on the street anyway.

It is proven that the 3.8 will make that kind of HP with the application of the right parts, conversely is not proven that any 4.3 stroked engine with a positive displacement blower will. I would suggest that you stick with proven parts and leave the experimenting to the people who have the background, experience and cash to play around. ;) Just my .02. :)
 
I used to drive my freinds 87 vette quite often he has a 15000 dollars alcohol motor in it with about 850 to the rear wheels now he has a normal motor that he put in about 10000 dollars in it is stroked tune port and it has to run race fuel in it most tiime I think he said it pushes 560 and that is his everyday driver. I have never diven a t-bird with that but I have driven a vette like that.
 
XR7 Dave said:
No matter how you cut it, 400+hp from our engines is a tall order and will require a lot of money. When you say you want that kind of power, do you have any idea what it is like to drive a car with that kind of power? It is easy to toss around numbers, but having driven a 400+rwhp SC I can tell you that you just can't use that kind of power on the street anyway.

It is proven that the 3.8 will make that kind of HP with the application of the right parts, conversely is not proven that any 4.3 stroked engine with a positive displacement blower will. I would suggest that you stick with proven parts and leave the experimenting to the people who have the background, experience and cash to play around. ;) Just my .02. :)

What about the 4.2 stroker
 
4.2 stroker

I have a 4.2 stroked engine as well as another club member from the Toronto area.I have asked Dave about the power output of these and he advised me that the stroked engine is more about torque than horsepower.He told me to expect about 50lbs of additional torque above a similar 3.8 engine build up.
 
The reason you need low compession & low boost with this motor.
Is because of poor combustion chamber shape.

With a long stroke motor your piston speed go's up.So you will need
to lower you redline RPM.

The reason for piston rock,is not because of shorter rods.
Its because with a stroker motor you will need extra clearance
between the bottom of piston to crankshaft ,So you need to run shorter
piston skirts.The shorter piston skirt causes the piston rock.

If you would go with a longer stroke than listed.And your piston
shirts turn out very short.You will need to install nylatron buttons.
To keep the piston skirts from rubbing the cylinder wall

MOLDEX can cut a new billet crank for your SC block,They start
around $3000.00 with all the bells and whisles


CORVETT PSSSSSST.Over price ,over ranked junk,plus they are driven mostly by momaboy sissies.just kidin :rolleyes:

THANKKS RANDY
 
scfix92 said:
I used to drive my freinds 87 vette quite often he has a 15000 dollars alcohol motor in it with about 850 to the rear wheels now he has a normal motor that he put in about 10000 dollars in it is stroked tune port and it has to run race fuel in it most tiime I think he said it pushes 560 and that is his everyday driver. I have never diven a t-bird with that but I have driven a vette like that.

Ok, so you can back up your HP numbers with some real world driving. I don't imagine a high HP SC is any harder to drive than a Vette, maybe easier.

The problem with the HP levels that you hope to achieve is not displacement. I guess that is mainly what I was getting at.

With forced induction torque is always going to be monstrous once the boost is in motion, so whether it's 450 or 500 really isn't going to be important. what does become an issue is the SC's motor being able to carry that torque number over a reasonable rpm range. The reason for this is the blower, not the motor itself. If you limit yourself with the M90, the only way you will get close to your goals is with a good dose of nitrous. These motors have proven to be fickle on the juice, so unless you have the ability to tune the motor continually and the pocketbook to cover the expected breakages, it's really not going to be a very successful endeaver.

So that brings you to the next option. Alternative sources of boost. I believe the twin screw may be able to support your desired HP levels, but your most logical choice would be to ditch the superchargers altogether and build a turbo motor. There is absolutely no reason to believe that 600rwhp isn't possible with reasonable reliability with a properly sized turbo. At that level, 50hp either way will be the last of your worries.

Any current stroker kits rely on cast cranks. Herein lies the problem with them. The forged 3.8 crank is worth it when running the high boost necessary for the HP levels you desire.
 
Scott Long said:
What is Anthony Rongo using a 3.8L crank still in his SC?
Dude, Anthony's motor is a crate reman from Ford. Only the heads and cam have been changed. :eek:
 
XR7 Dave said:
Dude, Anthony's motor is a crate reman from Ford. Only the heads and cam have been changed. :eek:

Whoa! His member page shows RWHP and Torque each well over 400. All that with pretty much all bolt ons?? Pause for thought, that.

.....and with a best in the low 13's, it does make you wonder why we do this sometimes..........

Ira
 
irar said:
Whoa! His member page shows RWHP and Torque each well over 400. All that with pretty much all bolt ons?? Pause for thought, that.

.....and with a best in the low 13's, it does make you wonder why we do this sometimes..........

Ira

Anthony's car ran that prior to the Whipple and with a failing AOD when his car made 345rwhp with the MP setup. My car is also a completely stock shortblock (other than cam) that has never been out of the car in 190K miles and it makes over 410rwhp and has run a best of 12.1 @ 115 spinning the slicks to the 60 ft mark. I know exactly why we do this. :D :cool:
 
XR7 Dave said:
Anthony's car ran that prior to the Whipple and with a failing AOD when his car made 345rwhp with the MP setup. My car is also a completely stock shortblock (other than cam) that has never been out of the car in 190K miles and it makes over 410rwhp and has run a best of 12.1 @ 115 spinning the slicks to the 60 ft mark. I know exactly why we do this. :D :cool:

Damn! :eek: Well, if Don didn't convince me to put it on the dyno before, I'm ready now!

Ira
 
Traction permitting Anythony could run 11's. Especially with the new blower.

Dave is close. Now thats impressive for both of them to be on stock bottom ends and no nitrous. Makes you wonder if you really need to spend the money on a built bottom end. Sooner or later you will need the stronger internals, but for head and cam swap and bolt ons if you can get into the 11's that is good. A few years ago the limit was 13.5's w/ bolt ons. I know why I do this.
 
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