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Topic: HO vs SO engines: Gasket differences? (Read 1316 times) previous topic - next topic

HO vs SO engines: Gasket differences?

I am well aware of the mechanical differences between an HO and SO 5.0, but what are the gasket differences? I have a 1987 5.0HO with unknown mileage and in unknown condition sitting on the floor in my garage, and a 60k mile non-HO 5.0 sitting in my car. I know the SO's bottom end is in good shape, so I'm thinking of upgrading my engine to HO specs using parts off the HO (and then rebuilding the HO at my leisure). This involves swapping the heads, cam and intake, which of course requires removal of the front cover - in other words, a complete gasket kit will be needed. I see all kinds of 5.0 EFI complete gasket kits for sale on eBay in the $75 range, but these kits say "NOT FOR HO ENGINES". There are a few HO gasket kits on eBay but they are not complete (they only include head and intake gaskets) and they are more expensive.

My question: What would prevent this "non-HO" gasket kit from working on an HO engine? The main gaskets (head, intake-to-head, upper-to-lower intake, front cover, water pump, exhaust manifold) should all be the same, shouldn't they? About the only gaskets I could see being different would be the throttle body and valve cover gaskets (non-HO use steel valve covers with cork gaskets, HO use aluminum with rubber, and HO has a bigger throttle body). I installed new rubber valve cover gaskets and HO-style aluminum valve covers a few months ago because the old ones were leaking badly all over the exhaust manifolds, and the rubber ones are reusable, so if that's the only difference I should be OK with the non-HO gasket kit, right?
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

HO vs SO engines: Gasket differences?

Reply #1 –
Wow. Learn something new every day. Did not know about the valvecover difference.
 
When I did my H.O. swap I cant remember what I asked for at the advance auto parts. But I still have the box laying around and I put the # in and for "see all this fits" h.o. AND s.o. cars came up. It does picture rubber VC gaskets and I do remember putting those in. As you said, bigger TB and stuff, but that's all. I remember everything looking the same as what I took off the engine, like the water pump and all that.
1987 20th Anniversary Cougar, 302 "5.0" GT-40 heads (F3ZE '93 Cobra) and TMoss Ported H.O. intake, H.O. camshaft
2.5" Duals, no cats, Flowmaster 40s, Richmond 3.73s w/ Trac-Lok, maxed out Baumann shift kit, 3000 RPM Dirty Dog non-lock TC
Aside from the Mustang crinkle headers, still looks like it's only 150 HP...
1988 Black XR7 Trick Flow top end, Tremec 3550
1988 Black XR7 Procharger P600B intercooled, Edelbrock Performer non-RPM heads, GT40 intake AOD, 13 PSI @5000 RPM. 93 octane

HO vs SO engines: Gasket differences?

Reply #2 –
Throttle body will be different as well as possibly the exaust(as ho uses headers).
Intake gaskets will be the same upper and lower,head gaskets will be as well,timing cover and oil pan will be the same as well.
Are you sure the gasket sets your looking at are not for the older no roller 302's???
I seen alot of stuff advertised as non ho and that usually means older sets and they are cheap as they do not have the injected gaskets.
I'll bet you that's the difference.
I wouldn't skimp on your gaskets,get a good felpro eng set and you should not have any problems for a long time.

HO vs SO engines: Gasket differences?

Reply #3 –
Since the exhaust ports are the same on all Windsor heads I'd guess the exhaust manifold/header gaskets would be the same. However, I just looked at the fine print in the eBay auction and although the title says "Fel-Pro Ford 5.0 1982-1987" the text says "Ford Car 1982-1985, Ford truck 1982-1987". The photo of the gasket kit shows the rectangular truck-type intake gaskets. I'm gonna guess the kit is for a non-roller engine.

I did find an HO kit for $120USD including shipping. Since the Canadian dollar is in the shiznitter again it's not particularly cheap. I must price the kit up from my parts supplier and see what I can get it for from them. Prolly work out to about the same, but with no worries of duty or brokerage fees, and I'd know I wasn't getting chinese knockoffs.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

HO vs SO engines: Gasket differences?

Reply #4 –
I have never heard any differences on the power plant gaskets from so to ho.

I had issues but it was isolated to water jackets on my 289ho heads not matching to the intake.

I would order a set of SO gaskets because there really isnt any differences other than the ones you already stated.

I would be interested in knowing how an HO lower intake gasket mates to an SO head with respect to the water jacket.  My bet is it is so close it does not matter but, there might be a small difference.  An SO lower intake gasket set to my 289 heads did not work and I had to order specific 289 intake gaskets.

HO vs SO engines: Gasket differences?

Reply #5 –
The throttle body gaskets are expensive, and the valve covers really shouldn't matter as long as they are tourqued right. The head gasket is missing the last hole on the front of the head, but you can punch it out if you want to give it better cooling.

I saw no difference between the water jackets on the lower intake... The lower intake is the same part number...
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

HO vs SO engines: Gasket differences?

Reply #6 –
Quote from: Haystack;250241
The head gasket is missing the last hole on the front of the head, but you can punch it out if you want to give it better cooling.

...


See,, now get out of my head!!
I did that very thing with a chissel thinking i was fugging up.  Later i was told the reason there was no holes up front is because of the more natural slope to the rear based on how the engine sites.  Im not really sure on this one.  I usually enlarge the water ports anyway between cylinders (the triangle shaped holes) because it would in my minds eye improve water flow.

Im not really sure why i see the water jacket hole missing on the forward part of some headgaskets.  My old 302 HG had the forward holes for water while the newer HG did not.

HO vs SO engines: Gasket differences?

Reply #7 –
Lower intakes ho and so are the same,the uppers are different.

HO vs SO engines: Gasket differences?

Reply #8 –
How much shipping does Summit racing charge? They have Felpro sets for $89.99, for 86-93 5.0. :burnout:
95 Ranger Splash 2.3
88 Tbird Sport :ies::ies:
5.0 SO, stainless shorty headers, w/ Magnaflow lers. KYB struts, KYB shocks. 5lug conversion from sn95 Mustang, subframe connectors, drilled and slotted rotors, 03 Mach 1 wheels. sequential taillights.140 speedo
 

HO vs SO engines: Gasket differences?

Reply #9 –
I bought my gaskets from Autozone separately and it was cheaper than buying them as a "set".
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..