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Questions about 91 Lx I just purchased

dragstang

New Member
I just purchased this mustang it’s set up for dragracing only I’m pretty new to all this technical stuff but this is what this car came with I am thinking about possibly putting nitrous on it does this set up look like a good set up for nitrous. This car supposedly runs in the 12s now. Should I change the heads? I have read that it’s better to have stock heads with nitrous.
 

347HO

Member
I'm not seeing what pistons.

Don't see what piston rings and gaps

Don't think those rockers are up to the task.

Don't see if the heads have been surfaced for power adder.

No information on head gasket thickness nor the "quench".

I read there's allegedly a high volume, oil pump however, no mention of oil drain-back modifications... This could be disastrous.

I'm sure I'm forgetting some things...
I suggest you do more investigating to educate yourself.
The more you read and ask questions, the more fun per dollar will follow.

Good luck and congrats on your new project.
 

dragstang

New Member
Yes I have a lot to learn and that all the info I have. I will see if I can get answers to the questions you had. Thanks for the reply
 

dragstang

New Member
I'm not seeing what pistons.

Don't see what piston rings and gaps

Don't think those rockers are up to the task.

Don't see if the heads have been surfaced for power adder.

No information on head gasket thickness nor the "quench".

I read there's allegedly a high volume, oil pump however, no mention of oil drain-back modifications... This could be disastrous.

I'm sure I'm forgetting some things...
I suggest you do more investigating to educate yourself.
The more you read and ask questions, the more fun per dollar will follow.

Good luck and congrats on your new project.
It has the milodon windage tray is the to slow the oil drain?
 

347HO

Member
I believe a "windage" tray is installed to help control oil from climbing the sides of the oil pan and block walls.
It does nothing to help drain oil back to the oil pan from the top end.

When you observe how oil travels from the pump thru the oil galleys, bearings, lifters, and how that oil returns to the pan... You will see it collects on top of the block valley and cylinder heads. You'll also see the oil drain back holes.

So, you run a high volume pump, but don't address getting the increase of collected oil on top of the engine back to the pump...

You should be able to google methods and techniques how to do this.

One last thing.
I suggest you measure the clearance from oil pickup horn to floor of oil pan.
9 out of 10 people don't have the correct clearance I bet.
 

broncojunkie

Well-Known Member
Very good info from 347HO! I will add that stock heads are almost never a better performance option than good aftermarket aluminum heads. Aluminum just dissipates heat better, which helps prevent detonation. You can typically get away with more timing advance and higher compression on pump gas. Add to that the fact that most aftermarket heads flow WAY better and you'll find that the increase in performance is pretty significant. Having said that, people ran nitrous through iron heads for decades. You just have to adjust accordingly, if you go that route. Aluminum heads are definitely more forgiving, though, when it comes to power adders.
 

347HO

Member
Pretty much any aftermarket aluminum head are good to great.
Just not "china" heads like pro form or whatever they're calling themselves now.
I recommend
Twisted wedge series
High ports
RHS
Bringing up the rear are the edelbrock series.
You will need to know what combustion chamber volume.

Aluminum heads are worth 1.0 point extra compression ratio vs iron heads... Which is why "bronco" stated aluminum heads are more forgiving on detonation.
 

347HO

Member
Pretty much any aftermarket aluminum head are good to great.
Just not "china" heads like pro form or whatever they're calling themselves now.
I recommend
Twisted wedge series
High ports
RHS
Bringing up the rear are the edelbrock series.
You will need to know what combustion chamber volume.

Aluminum heads are worth 1.0 point extra compression ratio vs iron heads... Which is why "bronco" stated aluminum heads are more forgiving on detonation.
AFR has a new budget head out now. I haven't researched them yet, but sounds promising.
Unfortunately, I have very little experience with AFR.
The one set I had for a customer on my flow bench 185 if I remember correctly, performed almost identical to the eddies.
This is old information, and AFR hopefully has upped their game.
 
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