sho dirt track car

[copperpacecar]

i have a 3.0 sho motor and trans in a 94 ford probe that i use for dirt track racing. what im trying to learn is what needs to be done to my motor to make sure i have it ready for racing and dont throw another rod. currently im running the rev limiter to 8400 rpm (to avoid a second to third shift into the corners, i know it doesnt help power) and im flooring it 15 out of every 25 seconds for an hour straight. i tried to search this topic but there seems to be very limited info. i dont mind sinking some cash into a motor, i just dont wanna be doing motors every month

 

[zach44102]

The motor should be fine in that rpm range, id just make sure you do rod bearings. But if you are keeping it upwards of 6500-8500 all the time with stock cams you would be better just keeping it in third. With stock cams that motor will make more power at 4500 then 7000.

As far as durability, make sure the rod bearings are done. The top end can take it.

 

[ShadetreeSHOguy]

What zach said, mainly get the rod bearings done. Even if the previous owner "said" they were done.

Also, MUST HAZ PICS OF SAID BEAST!

 

[frosho]

Sustained high RPMs, sustained g-loads in one direction (circle track)... I wonder if the bearings are being starved. Do you have an oil pressure gauge? I'm not familiar with your history. Have you blown multiple engines doing the circle tracks?

 

[Off Road SHO]

Get smaller tires up front and shift to third.

Tom

 

[rubydist]

it seems to me, given the volume of oil pumped inside the engine, that if you are running at that high of rpm for long periods of time, it would be good to have at least one extra quart of oil in the pan.

iirc, at 7000 rpm the thing is pumping 12 gallons per minute, or the entire capacity every 6.25 seconds. at 8400 rpm that is 20% more flow. given that it takes a certain amount of time for the oil to fall back to the pan from the top end, some extra oil in the system seems like a good idea.

 

[kevinspann]

What CAN you do by rules? No dry sump system?

 

[copperpacecar]

okay im gonna try and answer everyone...first, rules? haha rule one is no motor swaps so obviously rules dont matter to me...because that rule though the2 car picks someone requested wont look pretty. to hide the swap i removed the fenders and bumpers from the sho and did my best to mold them onto the probe but with a good eye you can still see that its not a taurus. i have pics and videos of the races on facebook and my profile isnt private if anyone wants to message me ill shoot them the info.....next is yes ive blown three motors this year as i didnt know the sho had rod issues. ill fix that next. i actually figured it was a high rpm issue. i know it doesnt make real power past 4500 rpm but avoiding the shift is worth more time and third is kinda doggishly slow in my opinion. ....so in u guys opinions with extra oil and rod bearings should the 3.2 or 3.0 be able t4o handle the 8500rpm abuse? also dry sump is an option...what suggestions do u have on this?

 

[frosho]

Must've missed my question about the oil pressure gauge...

It wouldn't surprise me if you're losing oil pressure due to starvation for the reasons I mentioned above. But you won't know unless you have a gauge to watch.

 

[copperpacecar]

i did forget to answer that....no i dont have a gauge...actaully i dont have any gauges. i had a motor that lasted over a year on the track without bearings or extra oil so id assumed i was safe without a gauge. only reason i lost that motor was to massive overheating and i actually have the motor in my garage just needs head gaskets

 

[Phoenix]

What kind of failures? Rod passing through block to say hello?

If you want endurance , you seriously need to keep this under 8k rpm. More then that is just asking for it.

Even with hot cams , the hp curve drops at 7600-7800. No need to go berserk at 8500. You might loose a couple milliseconds , but your engine will thank you.

At 8500 the lubing system cant keep up , I think piston #5 is the one that will suffer from oil deprivation. It will damage the bearing #5 and pretty soon you will need another block. (someone tried this (Ernie)- and #5 is always the culprit.)

 

[ShadetreeSHOguy]

What about pics?

 

[SHOtime2511]

+1 for pics.
We don't care how ugly it is,I for one enjoy ugly contraptions.
Best advice I would offer is that which has already been said.
#1 smaller wheel/tire combo and shift 3rd.
#2 run an extra qt of oil to keep the pickup from starving in corners.
#3 fresh rod bearings.

 

[copperpacecar]

okay everyone....i ordered the head gaskets and the the rod bearings. four questions though...first all is whats my torque sequence and amounts for the head bolts and are they torque to yield? next is whats the torque specs for rob bolts? should the rod bolts be replaced or can they be reused? lastly does anyone have a pic of the timing belt and assembly fully assembled on the 3.0? i disassembled the motor some time ago as i was converting a 3.2 to work with the manuel tranny and i was assuming id never use it again and im not100% how she goes back together.

 

[AREA 91]

You can't spin the engine that high an rpm for that long.

 

[allsho419]

I'm working on that same project, would love infor on how u did it.