A question before I start my build

[oneboredguy]

Is a big bore stroker worth the extra money vs a regular stroker or a regular 4.6? I already have a built 4r, sra and worked heads. I was thinking of making it a 5.3l and getting bigger valves so it will really flow. The power adder will be a big single turbo. Thanks in advance for your answers.

 

[Brutal Metal]

I'm a fan of the oem stroke with added compression and a small over bore to true the cylinders.. The Geometry of a stroked combo isn't the most bulletproof reliable with the modular ... John M runs a factory stroke in the Pro-Mod.

 

[Badasssapper67]

The benefit of the big bore, besides the cubes, is freeing up some space around the outside of the intake valves. I love the idea of my engine being more efficient and making better sense, BUT, you have to ask, "If I spent that $1500 else where would my engine make more power"?

Another thing about the big bore is, you're at the mercy of the skill level of who ever is going to perform the surgery. It's pretty much beyond the skill and equipment level of anyone doing his own upgrades so how do you know whom to trust? Deciding to go big bore it the BEGGINING of a lot of serious questions. If you use that money to go with great long tubes and a k member or $1500 of something else, you pretty much end up with answers not questions.

I want my Cobra to be "MY" Cobra so yeah I will one day big bore it. Before that, I plan on being able to bullet proof the engine. Billet oil pump, rear coolant cross over, etc. Then I'll start my search for someone I can count on to do the big bore right the first time.

Good luck.

 

[Nightmare302]

If you plan to throw much boost at it stay stock bore. The big bores have issues with head gaskets due to the lack of material between cylinders. Teksid with a tiny tiny bore just to clean it up, custom pistons and done.

 

[01yellercobra]

In my opinion, yes a big bore stroker is worth it. But you have to look at your overall budget. I think the last time I saw a Boss block it was about $1100. Then you have to track down a crank. I haven't heard enough about the new FRPP 5.3L to judge one way or the other.

I ran a big bore stroker because it's what I wanted since I got into modulars. I had a resleeved Teksid and after ordering a second set of pistons I found cracks in two cylinders. So I had a complete rotating assembly with no block. I ended up getting the Boss 5.0 block and assembled it myself. One of the reasons I went that route was because I wanted to run a centri, but wanted to maintain some torque down low. Which I did.

The way I look at it is can you hit 1000rwhp with 4.6? Sure. But it's a lot easier to hit it with 5.3L.

 

[Nightmare302]

In my opinion, yes a big bore stroker is worth it. But you have to look at your overall budget. I think the last time I saw a Boss block it was about $1100. Then you have to track down a crank. I haven't heard enough about the new FRPP 5.3L to judge one way or the other.

I ran a big bore stroker because it's what I wanted since I got into modulars. I had a resleeved Teksid and after ordering a second set of pistons I found cracks in two cylinders. So I had a complete rotating assembly with no block. I ended up getting the Boss 5.0 block and assembled it myself. One of the reasons I went that route was because I wanted to run a centri, but wanted to maintain some torque down low. Which I did.

The way I look at it is can you hit 1000rwhp with 4.6? Sure. But it's a lot easier to hit it with 5.3L.

Until it pops a headgasket or the mains walk.

 

[01yellercobra]

I never pushed mine hard enough to pop a head gasket. I think I was in the mid to high 600's. And I never had any signs of main caps walking. The OP asked what we thought. So I thought I'd give my experience.

 

[Nightmare302]

I never pushed mine hard enough to pop a head gasket. I think I was in the mid to high 600's. And I never had any signs of main caps walking. The OP asked what we thought. So I thought I'd give my experience.

You are right at sub 1krwhp levels the boss block is outstanding, it unshrouds the valves and makes more HP than the others. They just are chalk full of issues at the higher end of the spectrum. That's why I said if he plans to throw lots of boost at it.

 

[oneboredguy]

Thanks for all the info guys. I have a teksid right now that is .020 over and just needs a hone and it will be good to go. I was planning on doing oversized valves but that was only because I was planning on big bore. So since big bore is out for my power level what about a stroker? I know brutal metal said they have issues, anybody else have anything to add? I only am thinking about a stroker to help spool. I will have turbo cams and higher compression, but I want to build it once and be done, until something gives out eventually of course.

 

[olgreydog7]

I'd say you need to be more specific. What power level? What are your plans for the car? Can you actually live with that? There have been several members on here who have built 1000+RWHP monsters, then sold them and went for something much milder. Yea it's cool to say you have that much power, but it's another thing to live with it. I'm not just talking about its street manners. I'm talking broken parts. There's a reason race teams tear down and rebuild their engines after every race, if not every run. Power kills parts, even high end parts built by the best engine builders there are.

 

[oneboredguy]

I am going for 1k whp +. I'll have it turned down some for the street. It will be on race grade e85 when turned up. Pump e85 if it's turned down. It will go to the track once I'm a while. I will be traveling to tx2k and sct events.