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Topic: Rebuilding 5.0 HO...couple questions...first time build (Read 1840 times) previous topic - next topic

Rebuilding 5.0 HO...couple questions...first time build

I picked up a 92' continental HO and im completely rebuilding it.  2 things that have been on my mind are the bore, and the cylinder heads.  For the bore, im either going to go .030 over or .040 over....i figured go 40 because why not go as big as you can...but some people say it wont make a difference....will there be a difference between 30 and 40?  And about the cylinder heads...will there be a difference between putting new valves/springs/rocker arms in my stock cylinder heads, and putting them in gt40 cylinder heads? Thanks
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Rebuilding 5.0 HO...couple questions...first time build

Reply #1 –
gt40 heads are a pretty big improvement over the heads it rolled off the assembly line with.. as for .030 compared to .040 boring, it's such a small difference that you'd never really notice a difference.. .030 will make it a 306, which is a pretty good starting point to gain some extra power, provided the pistons you use are decent
ShadowMSC.com < < Still Under Construction

R.I.P. 'Zump' 8/29/86 - 11/11/11
3- 87 TC's / 1 really mean 83 Capri RS / 94 Sonoma SAS Project on 37x12.50 TSL Radials / 88 S10 that's LITERALLY cut to pieces / 84 F150 SAS, 351M, 39.5 TSL's / 85 Toyota regular cab, 22R 5spd, 3/4" drop, my little junkyard save/daily driver

Rebuilding 5.0 HO...couple questions...first time build

Reply #2 –
yeah that another thing...forged pistons or hypereutectic?  it was a pretty big deal in 93' apparently when the hypereutectic pistons came in the HO...but forged are stronger...idk what to use...and yeah gt40's are what id use...but any one id find would be old and need its innards replaced...so i was thinking if im going to replace everything inside would it make a difference buying gt40 heads, as opposed to just replacing the components in my stock heads...and would there be any DISadvantages to going .040 bore?
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Rebuilding 5.0 HO...couple questions...first time build

Reply #3 –
the only real disadvantage would be the fact that your cylinder walls will be .010 thinner. as far as rebuilding your stock heads, i wouldn't bother. ford put out some really py heads for the 5.0. the gt40's aren't 'amazing,' but they're a vast improvement. if your budget allows, i'd just buy aftermarket heads. there are tons of good heads that can be had for under a grand, ready to bolt on and go. if your budget is a little tight for that kind of expense, gt40's are the way to go. just because the heads are used with some mileage on them, doesn't mean you need to replace the valves, unless they're bent. you'd be perfectly safe with cleaning them up and putting them back in with new guide seals. as for valve springs, you'll need to replace them anyway if you're going with a performance cam. stock ford springs are pretty weak.

as for forged vs hyp., i'd go forged. if you want top of the line quality, i use keith black and je pistons in my personal .
ShadowMSC.com < < Still Under Construction

R.I.P. 'Zump' 8/29/86 - 11/11/11
3- 87 TC's / 1 really mean 83 Capri RS / 94 Sonoma SAS Project on 37x12.50 TSL Radials / 88 S10 that's LITERALLY cut to pieces / 84 F150 SAS, 351M, 39.5 TSL's / 85 Toyota regular cab, 22R 5spd, 3/4" drop, my little junkyard save/daily driver

Rebuilding 5.0 HO...couple questions...first time build

Reply #4 –
alright thats eye opening...if its not going to do any difference going .040 ill just do .030 and have stronger cylinder walls..forged is what i was thinking as well...je pistons is a brand that comes to mind for me but its kind of expensive for some of those...and the heads..idk...is there really going to be that much of a performance difference between aftermarket heads and GT-40?  i had it in my head gt-40, never really though of aftermarket...
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Rebuilding 5.0 HO...couple questions...first time build

Reply #5 –
yeah.. you always have to remember, OEM heads are built for some performance, but mostly to meet emission requirements. aftermarket heads have a better flow rate right off the shelf because they're born and bred for power. a nice set of aluminum pro comp heads could really awaken a motor
ShadowMSC.com < < Still Under Construction

R.I.P. 'Zump' 8/29/86 - 11/11/11
3- 87 TC's / 1 really mean 83 Capri RS / 94 Sonoma SAS Project on 37x12.50 TSL Radials / 88 S10 that's LITERALLY cut to pieces / 84 F150 SAS, 351M, 39.5 TSL's / 85 Toyota regular cab, 22R 5spd, 3/4" drop, my little junkyard save/daily driver

Rebuilding 5.0 HO...couple questions...first time build

Reply #6 –
alright ill look into it...thanks for the help
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor
 

Rebuilding 5.0 HO...couple questions...first time build

Reply #7 –
not a problem.. i make a living off these things lol
ShadowMSC.com < < Still Under Construction

R.I.P. 'Zump' 8/29/86 - 11/11/11
3- 87 TC's / 1 really mean 83 Capri RS / 94 Sonoma SAS Project on 37x12.50 TSL Radials / 88 S10 that's LITERALLY cut to pieces / 84 F150 SAS, 351M, 39.5 TSL's / 85 Toyota regular cab, 22R 5spd, 3/4" drop, my little junkyard save/daily driver