5.0 HO vs. SO v2.0 LOL

Topic: 5.0 HO vs. SO v2.0 LOL (Read 931 times) previous topic - next topic

5.0 HO vs. SO v2.0 LOL

August 20, 2008, 11:55:09 AM

I'm at a cross roads...

I want to rebuild my 5.0 in the 88'.

Question...

All intake trac/cam/head parts aside. Are the block and rotating assembly in the SO the same as the HO?

I'd love to just pick up a Summit Racing rebuild kit w/ forged pistons and get the machine work done and call it a day. OR.. Will I need to honestly upgrade to better crank/rods (least HO) if I want to aim for 300-350 crank HP?

Thanks

5.0 HO vs. SO v2.0 LOL

Reply #1 – August 20, 2008, 02:18:14 PM

The block and rotating assy are the same between the HO and SO. The only difference down below was the pistons and you're getting new ones so you're good to go :)

Quote from: GREYSHADOW;232843

I'd love to just pick up a Summit Racing rebuild kit w/ forged pistons and get the machine work done and call it a day.

That's exactly what I'm about to do with my 87 bird... Except for the forged pistons. I'm getting the Hypers. I'm just doing a stock 225 HP HO but I think if you're building a naturally aspirated 300-350 HP you'll be fine with the stock crank and rods. I would just upgrade the rod bolts to ARP wave locks. Just make sure you get the rotating assy balanced because your new piston arent going to weigh the same as the stockers and that will throw everything off.

Also make sure the pistons you order have reliefs for the heads you plan to use especially if you plan on running twisted wedges. I'm assuming if you have a 300-350 HP goal that you'll be using a 2.02/1.60 valve package in whatever aluminum head you plan to run.

5.0 HO vs. SO v2.0 LOL

Reply #2 – August 20, 2008, 05:22:27 PM

Quote

Also make sure the pistons you order have reliefs for the heads you plan to use especially if you plan on running twisted wedges.

You're gonna have to explain this one....
Twisted Wedge heads are designed to wor with flat tops to include the true flat tops found in 86 HO motors. I' running forged pistons with no valve reliefs. No clearance issues with a stage 1 cam and I'm debating on 1.7 rockers seeing as I have enough spring to support them and then some. My dish

5.0 HO vs. SO v2.0 LOL

Reply #3 – August 21, 2008, 02:16:28 AM

Well....

Something like a AFR 185 head is what I would be looking at. Cobra intake/65mm-70mm TB, E-303 cam or the like, rollaer rockers, prob 1.6's and the probly necessary MAF conversion in the range of a 76mm unit w/ 24lb- 30lb injectors.

OR...

I might build that same motor and just drop it into my 89' Notchback LOL.:flip:

5.0 HO vs. SO v2.0 LOL

Reply #4 – August 21, 2008, 06:42:27 AM

Quote from: Dogcharmer;232863

Also make sure the pistons you order have reliefs for the heads you plan to use especially if you plan on running twisted wedges. I'm assuming if you have a 300-350 HP goal that you'll be using a 2.02/1.60 valve package in whatever aluminum head you plan to run.

Unless you're running something similar to the TF Stage-3 cam(which ain't a street cam), NO valve reliefs are necessary, period... I've run the Stage 1 with '86 HO flat tops for almost nine years...

5.0 HO vs. SO v2.0 LOL

Reply #5 – August 21, 2008, 08:23:54 AM

I guess I would've been more correct if I would've said "especially if you plan on running inline valve heads"

Just to clarify... I suppose my train of thought was somewhere along the line that if you're getting new pistons anyway the reliefs might as well match the valve sizes and angles in the heads. To my mind having the proper valve reliefs just opens up alot more possibilities down the line when it comes to choosing a cam. (and alot less potential headaches)

That might not matter to people having a specific known combo in mind but if one was concidering going with a custom grind or one of the Comp XE cams it might be a shoot as to whether you'll be pulling your new flat tops out and having them flycut anyway after all is said and done.

To run most decent OTS cams with TW heads he doesn't nessesarily need TW specific pistons. All I'm saying is; if I was gonna spend the money on forged pistons and run TW's- why limit myself by getting forged flat tops with no valve reliefs?

All of this is moot since we now know he is looking at AFR 185's and an E cam... In this instance if it were me I would buy my pistons flycut for the 2.02/1.60 valves in those heads... I think we can all agree to that!

Just trying to be helpful :)

5.0 HO vs. SO v2.0 LOL

Reply #6 – August 22, 2008, 12:58:12 AM

Quote from: Dogcharmer;232978

I guess I would've been more correct if I would've said "especially if you plan on running inline valve heads"

Just to clarify... I suppose my train of thought was somewhere along the line that if you're getting new pistons anyway the reliefs might as well match the valve sizes and angles in the heads. To my mind having the proper valve reliefs just opens up alot more possibilities down the line when it comes to choosing a cam. (and alot less potential headaches)

That might not matter to people having a specific known combo in mind but if one was concidering going with a custom grind or one of the Comp XE cams it might be a shoot as to whether you'll be pulling your new flat tops out and having them flycut anyway after all is said and done.

To run most decent OTS cams with TW heads he doesn't nessesarily need TW specific pistons. All I'm saying is; if I was gonna spend the money on forged pistons and run TW's- why limit myself by getting forged flat tops with no valve reliefs?

All of this is moot since we now know he is looking at AFR 185's and an E cam... In this instance if it were me I would buy my pistons flycut for the 2.02/1.60 valves in those heads... I think we can all agree to that!

Just trying to be helpful :)

It's appreciated!!!