Recommend a stroker for a 4500 Ultra4 Jeep

[hurleygo3]

I've been lurking here for sometime, but never posted. I have a Jeep that I race in the Ultra4 series and King of the Hammers in the modified class. We placed 4th last year and this year we placed 3rd with a bone stock 120k 4.0l.

I'm in need of a motor with some more power and torque. I'm not looking for a fire breathing monster. First and foremost I want a solid reliable motor. I'd like some more torque and hp but not if it means reliablity.

I've been looking at crate motors like Golen, ATK and Blue Print. But I'd love to hear what some of you in the know would recommend for a solid race motor.

I have a 2000 and a 1994 motor I can use to build a solid motor from.

Thanks Mike
#4588

[Cheromaniac]

I suggest you build a modified poor man's 4.6L stroker and add baffles to the oil pan to prevent oil starvation during hard cornering. Simple, clean, and reliable.

[hurleygo3]

Thanks. I'll look into it.

[FlyinRyan]

Is this an OBDII Jeep? what does your class allow for as far as engine management?

[Desertjr]

I suggest you build a modified poor man's 4.6L stroker and add baffles to the oil pan to prevent oil starvation during hard cornering. Simple, clean, and reliable.

Can you link us or possibly post pictures Dino. I did copy your oil pan mod, but what else would be beneficial while I'm here?

To add to the thread, you said 2000 & a 94?. The 2000 is the better block, also has a crack girdle. The 94 has the better head. Of course the 99 style intakes better. A lot claim low end gains..idk as I'm coming from a tired renix to a built motor lol. But I've got a "horse shoe" intake on it.

[hurleygo3]

Well I picked up a Hesco built motor with aluminum head, Borla headers, and roller rockers. I pulled the motor apart and installed new bearings. It seems that the block has been machined. It has 4.0l rods and Diamond pistons. At TDC the pistons stick out of the block .012. With a MLS head gasket that leaves me with .031clearance and 10.31:1 compression. If I go with a factory gasket .051 that will bring the compression down to 10.1:1 and clearance up to 0.039.
This is a motor that's only going to be raced. What gasket would you go with? Or would you just get a new block and go with a 0.0 deck clearance?

[Desertjr]

Well I picked up a Hesco built motor with aluminum head, Borla headers, and roller rockers. I pulled the motor apart and installed new bearings. It seems that the block has been machined. It has 4.0l rods and Diamond pistons. At TDC the pistons stick out of the block .012. With a MLS head gasket that leaves me with .031clearance and 10.31:1 compression. If I go with a factory gasket .051 that will bring the compression down to 10.1:1 and clearance up to 0.039.
This is a motor that's only going to be raced. What gasket would you go with? Or would you just get a new block and go with a 0.0 deck clearance?

Haha no. Way your in my exact spot. I'm also .012 above deck. I decided on the stock .051 gasket as the extra .08 quench doesn't seem worth the gain but i did it mainly to drop my compression enough for my setup on 87 octane. And the extra clearence wouldn't matter in my case. Stock limit of 5500rpm at most, I'd wouldn't have a clearance issue at all.

What rpm will you be running? You'll deffinetely need race gas no matter what with that compression. And cam lift may come into play. But I've seen a. Few motors with the quench height in the .02x range with no issue running today. Richard a,a goatman being 1 of them I think. Russ pottenger build it as well as the naxja ultra4s motor. You may talk to him for some info?
He's a busy guy but great work and great info and very very patient. Couldn't say enough about him. Buehl racing engines is what I believe his shop name is. Look around on naxja SoCal sectional you'll see everyone recommends him.

[SilverXJ]

Well I picked up a Hesco built motor with aluminum head, Borla headers, and roller rockers. I pulled the motor apart and installed new bearings. It seems that the block has been machined. It has 4.0l rods and Diamond pistons. At TDC the pistons stick out of the block .012. With a MLS head gasket that leaves me with .031clearance and 10.31:1 compression. If I go with a factory gasket .051 that will bring the compression down to 10.1:1 and clearance up to 0.039.
This is a motor that's only going to be raced. What gasket would you go with? Or would you just get a new block and go with a 0.0 deck clearance?

What is the CC on the piston dish? That is getting awfully close on the quench, but if the engine was ran previously like that I would run it. Also, being a race engine you may be able to use race gas which will combat pinging.

[shawnxj]

wouldn't the aluminium head help with the pinging as well? shouldn't have the hotspots that the steel heads have

[SilverXJ]

LOL... see.. I read that part.. about the aluminum head.. but when replying it completely left the room.. so yeah., with the Aluminum head you can run a lower octane because the head cools the combustion chamber better.

[Desertjr]

LOL... see.. I read that part.. about the aluminum head.. but when replying it completely left the room.. so yeah., with the Aluminum head you can run a lower octane because the head cools the combustion chamber better.

I missed it as well

[Cheromaniac]

Can you link us or possibly post pictures Dino. I did copy your oil pan mod, but what else would be beneficial while I'm here?

http://www.angelfire.com/my/fan/HVOP.html

[hurleygo3]

Thanks for the replies. The pistons have 21cc of dish. I think I'm going to run the factory gasket and see how it goes. The motor had been spinning at close to 7,000rpms I'm not going to run it over 5,500rpms. I just want to be able to run 91. Race gas is just a pain.

I've been talking to a few different people about fuel management. From stock PCM, flyinryan to a stand alone FAST system. What's your thoughts on a fuel system?

[shawnxj]

i went with megasquirt 3. should have it wired in this weekend

[racing89]

No race fuel required. I am running simular specs( with higher compression) with no problems on high test.