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Topic: Talking cylinder heads. (Read 5318 times) previous topic - next topic

Talking cylinder heads.

Reply #15
Quote from: 5.0thunderbird;411987
I want the car to end up at the 350-400hp range when I'm finished can that be acheived with the 5.0?

Not easily with the gt40p's, and really not possible if you aren't taking it up to higher rpms. Are you using the AOD? The thing shifts early. Horsepower will equal torque at 5252.1rpms.

With a 302 or 306, you really need to take it to 5500-6000 rpms to pass 400hp, and this will be with good flowing parts. Aftermarket heads will get someone 350hp at 5k rpms.

Planning on sticking with the HO cam?
1988 Thunderbird Sport

Talking cylinder heads.

Reply #16
Idk if I can go with anything bigger than the HO can because of valve to piston clearance. Is that going to be an issue?

Talking cylinder heads.

Reply #17
Thats right...I forgot about the flat pistons of SO 5.0...

So you are stuck with a stockish type of cam....even with the best aftermarket heads, its going to be tough to make the power.  6000-6500 with AOD....death.

Plus all the other upgrades that would be needed...

Or you can bolt the gt40p on and enjoy the 20-30HP...

Travis

Talking cylinder heads.

Reply #18
I think what i am going to do is bolt on the heads and have a little fun. But i think starting this spring im going to built a 5.0 with some mahle motersports connecting rods and pistons so i can go all out with the thunderbird and create the desired hp that I want.

Talking cylinder heads.

Reply #19
I am telling you that if you do the heads, intake, TB, stock cam, and switch over to mass air you will have a little learning curve with the added hp and torque with the SO short block.  Many people have run larger cams with the SO short blocks and its pretty easy to call Comp Cams and have them spec one.  I am not saying you buy one but have them spec it so you can see if you can come up with something close (be conservative) that is used and then just clay it before you final assemble everything.  Do some searching on here and there are several threads on this very topic.  What you are going to get is a fun car to drive that will be super reliable and make around 250 to 275 rwhp.

Now if you are going to build a motor after doing this work to your SO short block I would highly advise that you to build a 331 or 347 if you want to stay with a 302 based motor to build the hp that you want.  Just realize that if you bolt on heads and intakes meant for a 302 on a larger displacement motor you will most likely build 302 power.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Talking cylinder heads.

Reply #20
Just build a GT40/GT40P spec'd motor and use the HO cam, you'll be happy. They will work fine on the stock shortblock. You can easily make 300hp at that point, and possibly a bit more. The car will drive very well. Yo said you want to use a Cobra intake so it sounds like you're already on the right track.

You have the heads
$100-$150 - Explorer intake (or $250-300 for Cobra - they perform the same)
$50 65mm or 70mm throttle body
You have the exhaust
$50 HO cam
$50 mass air sensor (recommended)
$50 mass air 4-wire harness

What am I missing? Just adjust the TV cable under the throttle body to provide more pressure and you'll be happy with the firmer shifts and delayed shift points. I think 260rwhp minimum is pretty common for the engine combo, which would be 300-310hp at the crank, somewhere around 5k rpms. It's much more fun than the puny 150-155hp these cars made when the engines were fresh.
1988 Thunderbird Sport

Talking cylinder heads.

Reply #21
I think ford should have put the HO in the tbirds and cougars but we all have to work with what we've got. And another question I have is how much HP can i possibly push out of the SO with the stock pistons?

Talking cylinder heads.

Reply #22
The pistons are fine as-is with the upgraded NA parts - don't worry about them. They'd mostly be an issue if you went with an aggressive cam, or power adders such as nitrous or forced induction.
1988 Thunderbird Sport

Talking cylinder heads.

Reply #23
I'm going as far as nitrous lol. I think the biggest cam I'm gonna be putting in with it is the stock HO or maybe there is another cam that is bigger but can work with the SO pistons


Talking cylinder heads.

Reply #25
Holler at Vinnie, I think he had a E cam in his SO short block back in the day.  I have read that a few guys are running 1.7 roller rockers with the stock 85-89 HO cam with the SO short block with P heads.  This is all just what I have read so I would still give Comp a call and see what they would recommend.  An you really need to buy an extra head gasket and clay the PTV clearance before completely assembling the motor.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Talking cylinder heads.

Reply #26
As an example the set up in my sig (with a 65mm TB) made 290 flywheel horsepower, based on quarter mile track times. With a swap to the Edelbrock Performers (keeping the 65mm TB) and nothing else the car picked up 40 horsepower, based on the car picking up 4 mph at the track. Basing the horsepower estimate on track times the car is making about 330 flywheel horsepower with just a head swap. The cam I'm running is just slightly above a stock HO cam.

Depending on cam selection you should be able to make anywhere between 280-300 flywheel horsepower with iron GT40/GT40P easily.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Talking cylinder heads.

Reply #27
Every time I see this thread my inner child is imagining talking heads ;)
[SIGPIC][/SIGPIC]:ford:87 Turbo Coupe through the floor sub frame connectors, 5.8 swap Ford racing heads Harland sharp 1.6 rockers BBK shorty swap headers 2 1/2 BBk X pipe magnaflow ler's. Megasquirt 2 with 36lbs injectors on hurricane intake with 4150 throttle body.Tremec TKO 600 Quicktime blowsheild spec stage 3 clutch. 3.73 gears and still not done

Talking cylinder heads.

Reply #28
Quote from: thewestie;412102
Every time I see this thread my inner child is imagining talking heads ;)

Hehe...well after reading this thread again...I like the idea of a SO 5.0 with GT40P heads, intakes, TB, mass conversion...nice 275-300hp flywheel package...will destroy the stock AOD quickly...

Travis

Talking cylinder heads.

Reply #29
You really think that the trans can't handle that power? Would I have to do a full trans swap?