75' IH 436SV

[bluethunder73]

I am in the process of building up a 75' 392. It has been bored 0.040 over and offset ground to a 4.00" stroke. With it now being a 436, gaining 44 cu.in. It would also need longer rods to gain the full stroke. I have a custom set of groden nitrous/blower rods(which took forever to get) and also wiseco pistons. As far as I have heard from both I have the first ever pistons and rods for an IH from their companies. The new stroke and piston have created a 10.25:1 compression. I plan on running the motor on 91 octane by recurving the distributor and also the heads have been milled I believe 0.015 to help lower the cc's of the combustion chamber to prevent pre-igniton. The cam is schneiders 295h grind being the largest cam for an IH without going custom. And of course I am using bbc springs to handle it all. Also I have fully ported and polished the heads and tested them, the best intake flow was 255cfm and exhaust was 155cfm. Helping to correct this is the stock rockers of 1.6 int. And 1.7 exh. And the cam is slightly bigger for the exhaust than on the intake side. I gladly removed the smog ports and pluged the unnessecary holes left by them. To gain a little more I will block off the heat crossover holes with thin aluminum. In the future I will weld the intake heat crossover passages of and tap them for a coolant fitting so that I can turn on the passage whenever I want or turn it off for a small boost. The intake has been gasket matched and also I have turned the spreadbore design into a copy of the edlebrock performer manifold by joining the primaries with the secondaries. The igniton system has been upgraded with an msd 6al box, and accel plug wires. Later I will add a pertronix ignitor and msd blaster coil. Also as said before the distributor is being re-curved. The exhaust is taken care of with stans headers(not the block huggers) and are chromed. I would like to cut off the collectors to lengthen the primary tubing and convert them to tri-y with a new length of collector tubing. It then goes through 2-1/2 in" true duals with a 12" glasspack on each side and a 4"x18" tip to exit through.
If I remember right, all together according to the computer program engine analyzer 3.2v(accurate within 10%) I will make 452hp @ 5,000rpm and 516ft. Lbs at 4,000rpm. All together my rotating assembly lost 10lbs. I have also upgraded the fuel system with a Holley electric blue pump, oil psi safety switch, and relay.

 

[Scoutboy74]

Whoa dude! That sounds pretty flippin' cool! Would you be so kind as to post some you tube video of the engine after you get it fired and link it through the IH video section sub forum? I bet it will make the ground shake!

 

[bluethunder73]

No problem

 

[Provience]

That sounds like one sweet motor! What are you putting it in?

 

[Robert Kenney]

Sounds like you have a very cool project going there. Would luv to see it make some dyno pulls.

just a couple of questions.


Have you mocked it up yet? Rod and cam interferance is very possible based on my preliminary measurments and 4.0" stroke and small profile big end steel rods.

Aluminum blower rods??? Hope you went steel if building this one for the street (I kow groden likes aluminum). All aluminum rods have an untimate fatigue life and are subject to fracturing. We run 60-80 passes on the bill miller rods in the funny car and toss them.

Also it you stroke a given crank/block configuration a shorter rod is usually required or a significant reduction in compression height. Stock rod c to c and you are right at 1.69 rr with a 4 "stroke

 

[MarkO]

It sounds as if you have spent a lot of time and $$$ on your engine.

The question I have is what exactly are you trying to achieve?

If you were wanting more cubic inches an easier way in which to achieve that goal would have been to find an mv446 or an lv478. Both could be made to fit a light line vehicle.

The other question I have is why are you wanting to try and make an sv engine turn so fast?

The basic design of the engine is to make the hp and torque at lower speeds. Turning the engine a whole lot faster won't make appreciably greater hp or torque.

But, it is your project and what I would do isn't what you have decided to do.

Good luck.

 

[Robert Kenney]

5k is not fast for an sv. The cam he chose will make great power @ 5k with the port flow numbers he posted.. Imho of course

 

[bluethunder73]

I was skeptical about aluminum rods as well but both the machine shop and groden thought they would work just fine on the street. You probably already know that groden makes a light weight rod, a nitrous/blower rod and then an even heavier one for 2,000+ hp. So its a gamble basically but I hear good things about groden so this will be a good test. Also that funny car is most likely turning alot more power than what this will, and I don't plan on any nitrous or blower(at least not yet). The rods I belive are 6.85in" long. And the reason why I choose a 392 instead of one of the mv motors for the weight factor and size. I know they don't weigh to awful much more than a 392 but it all adds up. Plus the custom prices would have gone up for some of the pieces. And to have a lightweight intake that they make for the sv series I would have to make a sheetmetal one for the mv or lv series. Which I could make custom to make all sorts of power but this would sacrifice alot of torque on the bottom, taking the streetable factor away since IH built things extra heavy. This truck is able to hit the pavement but can also go tear it up in the mud or even pull. And about the rod interferience with the cam I don't konw yet. The machine shop put a coating on the rod bearings and I haven't got them yet. But they should have done the math ahead of all the custom work. The motor will go into a 1973 1210 pick-up with a heavy heavy flatbed. I will try to get a few pictures up within the next week.
Some more of the numbers on the program as well are 1,500rpm only 80hp but 259ft.lbs and at 2,000rpm it makes 340ft.lbs. I know the horsepower isn't much on the bottom but its torque to get you moving and horsepower on the top end to keep you moving.

 

[Robert Kenney]

Below is a link to generally accepted aluminum fatigue theory. Good solid and proven. It is accepted that aluminum will fail under a very wide loading schedule and a fixed number of cycles regardless of magnitude of load/flex.

You are going to be very easy on them so I really have no basis to recommend an inspection regime.

Aluminum fatigue

As for the fc, yes 2000+ hp and 9000-9500 rpm through the lights but they are the heaviest bm rods that are good for nitro methane and we run methanol and a blower.

 

[Michael Mayben]

No need to "block" the heat crossovers on the intake manifold gaskets. Simply use lpg (propane) intake gaskets, those have the crossover blocked.

Propane intake gaskets are available for all versions of the sv engines including both ic and non-ic 392.

I run the propane gaskets on my ic 392 and have been for going on three years with the setup described here:

http://www.forums.IHPartsAmerica.com/carb-tech/76-beer-can-maneefol-guapo.html

 

[bluethunder73]

Thanks for the tip

 

[bluethunder73]

I found out I do have the improved cooling block, which will be helpful since the stroker will porduce alot of heat. Also I checked rod to cam clearance and I easily have .110 clearance, well over the required .060 so that was good news. Also here are some pictures of the truck without the off-road lights(I have to take them off so I can fit in my fathers shop) and also the motor I have in it right now.(73' 345 with isky's biggest cam, headers, and a quadrajet carb) the old motor needs rebuilding for sure and will be blown out of the water with the new one.

 

[Michael Mayben]

With the exception of color, yore ride and my ride could be one more breedin' pair:

http://www.forums.IHPartsAmerica.com/readers-rides/2945-beaters-third-life-2.html

 

[bluethunder73]

Alright so I have some specs for the build. I have not done final tuning nor have I dynoed the motor but it runs great I also have more pictures but am having trouble posting. To give you an idea of the improvement, I test my vehicles from one point to another where I turn on to a highway and test speed to a telephone pole. The original mildly built 345 could hit 62 max, my bodies 89' firebird can hit 77 no big suprise it weighs half as much, the new motor hits 75mph and that is with a terrible bog(which I am fixing with the electric fuel pump to make up for the stock pump)

block:
-bored 0.040 over
-flash ground and cleand

crankshaft:
-offset ground to 4.00" stroke(11/32" change)
-polished
-I want to say 0.0015" main clearances

rods:
-groden custom aluminum solid beam(nitrous/blower application)
-I believe 0.003 clearance
-there is 0.017 - 0.02 rod to rod clearance
-0.115 rod to cam clearance

pistons:
-wiseco custom flattop
-10.25:1 compression with 1/16" rings

heads:
-milled I believe 0.015 to help compression and lower chamber cc's
-fully ported and polished
-3 angle valve job and backcuts on intake valves
-9 stand rocker shafts

camshaft:
-schneider racing cams 295 grind
-220,228 duration and 0.050
-112 lca -0.448, 0.493 lift
-bbc valve springs w/ steel retainers and locks

intake:
-cast iron spreadbore
-machined to look like edlebrock performer
-runners gasket matched
-heat crossover blocked

carb:
-750cfm qjet

fuel system:
-Holley blue electric pump and regulator
-relay and oil psi switch
-3/8" line
-91 octane

ignition:
-quicker advanced Holley curved point Holley distributor
-modified vacuum advance
-distributor timing set at 5 degree advanced
-msd 6-al
-accel superstock 8mm plug wires and 0.045 plug gap

exhaust:
-stans 4-1 headers
-2 1/2" true dual
-12" glasspacks
-18"x4" tips

-180 degree thermostat

 

[bluethunder73]

New motor

 

[Jonsalter74]

Do you have the specs on your rods? Length, journal size, pin size? I like your set up and just picked up a 392, my wheels are spinning about doing this?

 

[bluethunder73]

I want to say the rods are 6.85 inches long, but can't remember completely. If you want you can call kieth groden at groden racing rods, he is the man who built them. He took forever and I did have to get the rods machined for correct clearance (rod-to-rod) but that could have been my machine shops problem. And the pins were from a small block Chevy, since the rods and pistons were both custom then the shop went with a floating pin that was common and lighter than the original IH. So if aluminum is ok with you then you can actually get the same ones I have from groden. The motor is working great and needs final tuning but I am completely satisfied with the results. I almost forgot the rods made were actually for a nitrous/blower application but that was more so just for the extra strength on the street, groden makes a lighter weight rod yet but you will compromise longevity on the street for a few grams.

 

[bluethunder73]

So, I am taking for ever to completely tune my new engine but I do know that it will roast the tires now for an easy 100ft, and I also have to be weary of policeman in town now. Warrensburg, mo has no noise ordinance but if someone thinks you are to loud then you can get in trouble, so I found out Friday night that a state trooper thought I was to loud I do have street legal exhaust but I must say the new motor is a screamer

 

[gulfdawg]

Just found this thread and wow. I have thought and dreamed of an engine build like this and to see it come together in a truck is awesome. It has been a while since the last post, just wondering how the engine is doing? Any youtube videos?
Thanks justin

 

[bluethunder73]

It runs really well but still can't make the time to fully tune it, and I would like to make some videos as well but nothing yet and will inform on here when I do.