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Topic: 5.0 SO to a 5.0HO (Read 1612 times) previous topic - next topic

5.0 SO to a 5.0HO

Hey guys! I used to post on the old forum back in the day when i had an 88 tbird (http://www.sounddomain.com/id/mike969) but i sold it, now i have been looking for another one so i found an 87 wit a 5.0SO what parts do i need to change to make it an HO? Any change in ECU or anything? getting the car for 150 which is best deal i found on a fox body, one guy wanted 500 for a TC without engine and hasn't run in 10 yrs.

Re: 5.0 SO to a 5.0HO

Reply #2 –
thanks i forgot about erics site!

Re: 5.0 SO to a 5.0HO

Reply #3 –
No prob.. I've been pondering the details of it a lot lately.. whether I should go through with a SO-to-HO rebuild of my own, or try to find a replacement (HO) to swap in.

Re: 5.0 SO to a 5.0HO

Reply #4 –
yeah well probably go through this route since i wanna go ahead and get aftermarket parts anyways, intake, roller cam etc. But was reading and am a lil lost now, on erics site it says "anything more potent than the stock HO camshaft will result in serious piston-to-valve clearance problems and/or driveability problems." but if we switch heads is that still a problem or what?

what would resolve this issues and let me use a more potent camshaft?

Re: 5.0 SO to a 5.0HO

Reply #5 –
The SO pistons are flat-tops with no valve reliefs. I think the TrickFlow Twisted Wedge heads are one way around it.. and there are a few other workarounds that have been discussed around here.. but since I'd need to deal with some bad rings in mine anyway, if I rebuild it I'll probably just get a rebuild kit w/ pistons that have valve reliefs on 'em.

Re: 5.0 SO to a 5.0HO

Reply #6 –
what is the quickest most cost efficient way to 300hp from an SO, there is no point for me to go to stock mustang parts if i want more hp anyways. If i have an SO according to my friend a rebuild on the bottom is gonna be necessary if i want to use a more agressive than stock came? Basically wanna know parts to get?

Aftermarket TB 70mm, correct? or bigger? Edelbrock or bbk?
E303 cam or something more aggressive from after market company?
Heads - which brand and model?
Injectors to i upgrade to 24lb if looking for 300hp?
MAP sensor for stang
ECU from stang
And dual flowmaster exhaust.

Really need some recommendations and sorry for being a noob, finally going to the point i never reached wit my old tbird, the performance part.

Re: 5.0 SO to a 5.0HO

Reply #7 –
70mm tb will do just fine,any company.
E303 great cam
Heads,Afr 165's would be best but are pricy,twisted wedge then edelbrock performers.
The ford motor sport heads being last on the list.
24lb inj,good.
map sensor is the same,stang or not.
Ecu would definetley have to be from a stang,but you have to go maf if your going with a cam so an A9P ecu for auto or A9L for stick are your choices.
Shorty 1 5/8 headers are a must and a good cat back 2'1/2" exaust.
That all should net you about 300hp,i've got all of it ready to put on and am curious how it will move.
Good luck with your mods.

Re: 5.0 SO to a 5.0HO

Reply #8 –
I have the Twisted Wedge heads on a stock '86 HO flat top piston 5.0, also have the Trick Flow Stage1 cam and most of the other goodies dominator listed.  I est crank hp at approx 330... Anyway I was .3 sec faster than a new automatic GTO at the track last weekend. His best was 8.75, mine was 8.41(1/8 mi)..

Re: 5.0 SO to a 5.0HO

Reply #9 –
the 86 flat top pistons in a 5.0 mustang is the sames as the ones in an 86-88 tbird/cougar correct? yet you managed to still get 300 hp without a problem? And the cam had no problem at all with that?

What are the specs on the stage one cam from trick flow? and you never rebuilt your bottom end?

Also never mentioned which intake manifolds to go wit? how is a gt-40 off of a cobra? i know i can get a used one for 200 or so.
 

Re: 5.0 SO to a 5.0HO

Reply #10 –
My Engine was freshened with new rings and bearings, but not rebored. Had a freind check it out and even at 134K, it had less than .001 cylinder wear. The complete specs are....

Std bore '86 HO LSC short block with orig flat top pistons(same as SO, but the SO after '87 may not be forged). Trick Flow heads and Stage-1 cam(499/.510 lift, 221*/225* @.050), Crane 1.6 roller rockers, GT40 intake, 65mm T-body, 24lb inj, 75mm Pro-M mass air meter, A9P EEC(now a C3W1 Ford Racing, but really no difference).

Exaust.. 1 5/8" BBK shorty headers, full 2 1/2" Hooker exaust system with three chamber Flow Masters.

Tranny... '90 3.8 Super Coupe AOD with Trans-Go shift kit and hardened input shaft, 2600 Stallion converter.

Rear.. Stock 3.73 Turbo Coupe