95Bluestallion's head swap pic thread

[95BlueStallion]

As Ive talked about previously I swapped over to some Thumper ported GT40P's. This was my first head swap, and Im not quite done yet, but thought I would share a few pics of my progress. Looks like I will be utilizing Bob Kurgan for a dyno tune, as my previous chip burner is not available. I want to see what kind of power I will be making with the stock cam anyway. My combo is:

Stock shortblock including stock cam, 93,000 miles
Thumper ported GT40P's
Scorpion 1.72 pedestal mount roller rockers
Trickflow street heat upper and lower
Edelbrock 70 mm throttle body
FRPP 42 lb injectors
Pro M 80 mm MAF calibrated for 24's
BBK 255 lph fuel pump
BBK unequal shorties
Pypes O/R X
Magnapacks
No smog, EGR, or A/C

I have the big injectors so I can bolt on a blower next summer. Feel free to guess my power if you want, I hope to set up an appt with Bob in the next couple weeks. Here are some pics, but I didnt take them step by step or anything. Lastly, the car is no show car, so I was going for a stock look other than the intake. I didnt take time to clean and paint everything and whatnot.

 

[JJ95GTID]

I will guess 255rwhp.


As far as the head swap I've seen that view of the engine bay more than enough times.
And, I will again once I get my aluminum heads resurfaced and have time to do the head swap.
I blew a head gasket with the supercharger and over heated the engine.
I tried 3 times to reinstall the aluminum heads with new gaskets and each time I got oil and water mixing.
I even switched over from head bolts to studs on the last attempt with no luck.
I decided to throw the stock E7TEs back on. I had to rush to get the car to run to move to another city.
Currently have about 1k miles with the stock heads bolted on without the chocolate milkshake.

 

[OrangeMustangGt]

Very nice!

I have had great luck with my gt-40p's however they are stock!
I wonder how much power the thumper porting is worth?
If i remember, my car made 270/310 tq at the wheels with gt-40p's, crane 2031 cam, explorer intake.

The only thing I wished you would have done was install ARP head studs and some fel-pro MLS gaskets if you plan to boost.....because you will be seeing the piston tops again when you install a blower with any decent amount of boost!

*edit, I see you Do have arp studs

 

[ProKiller]

24# injectors are hardly big especially if your going blower. I assume you'll be running an FMU with the 24s. If not, your going to need 42#s.

Good build though for sure. Do you have any pics of the head port work?

 

[RatStang]

24# injectors are hardly big especially if your going blower. I assume you'll be running an FMU with the 24s. If not, your going to need 42#s.

Good build though for sure. Do you have any pics of the head port work?

My combo is:

Stock shortblock including stock cam, 93,000 miles
Thumper ported GT40P's
Scorpion 1.72 pedestal mount roller rockers
Trickflow street heat upper and lower
Edelbrock 70 mm throttle body
FRPP 42 lb injectors
Pro M 80 mm MAF calibrated for 24's
BBK 255 lph fuel pump
BBK unequal shorties
Pypes O/R X
Magnapacks
No smog, EGR, or A/C

 

[ProKiller]

i missed that part, but you say your MAF is cal'd for 24s.

 

[divit250r]

I'm gonna guess around 255-265. The stock cam isn't so bad, but I'd love to swap it out myself.

 

[95BlueStallion]

i missed that part, but you say your MAF is cal'd for 24s.

The Maf is calibrated for 24's since I will be running it N/A for a while. I have some crappy pics of the port work, mostly just the intake and exhaust runners since he reassembled the heads for me. I took them using a washer to show the difference in size from the E7's for my Dad.

Orange, not only did he port them, but he did a 5 angle valve job and upgraded them to the bigger GT40 exhaust valves with stiffer springs. Im hoping its worth the cost...

Divit, I stuck with the stock cam for tunability and drivability, and also because Ive read it works well in boosted applications. The guy I had burning me a chip hasnt kept in contact, so I will be getting it dyno tuned after all, but oh well.

 

[95BlueStallion]

I didnt shrink these, so hopefully they arent too big...

E7 exhaust port:

Ported GT40P exhaust port:

E7 intake port:

Ported GT40P intake port:

I should have stood the heads up side by side for the valve pics, but wasnt really thinking about it.

E7's

GT40P's

 

[95BlueStallion]

Lol, turns out they are pretty big... Oh well, now you can see the detail I guess.

 

[MysteryMachine]

Sweet. I like to tinker with mine here and there, too much and I get pissed off at how ****ty it is. Glad to see your changing yours up a little

 

[95BlueStallion]

After reading my combo, would you guys expect the car to start without a tune? I figured it may, or may not with those big injectors drowning the engine. I gave it a try today after I finished putting it together, and it wont start. Im not sure if its because of the huge amount of fuel, or timing being off, or what. I have spark coming off the coil, and fuel pressure it at 30 PSI, but it just turns over and over. What do you guys think is going on?

 

[alleymad95GT]

I think what is wrong is that you have 42# injectors and a 24# MAF.

The computer is reacting to the MAF readings and sending a signal that corresponds to what the engine would need fuel wise running 24# injectors. But, your injectors are 42#, so you are getting way too much fuel.

Either get some 24# injectors or get a sample tube that matches the 42# injectors. Do that and I bet you can get it running pretty darn good just by messing with the fuel pressure a little bit.

 

[95BlueStallion]

Well I know what you mean, but I thought it would at least start and run like **** as is. Im not changing the MAF because it is calibrated for my N/A combo as it sits now. I just need someone to burn me a chip, or else suck it up and drop the cash for a dyno tune and get the 42's under control. I wont be able to afford the blower until next summer (3 month old boy), but didnt want to buy injectors twice. Anybody else have an opinion about it?

 

[alleymad95GT]

Im not changing the MAF because it is calibrated for my N/A combo as it sits now.

Well, actually, no. If it was calibrated properly, it would run. That is exactly the problem. The MAF is not calibrated for the injectors you have.

You are giving the engine almost twice the amount of fuel that it needs to run.

Personally, I do not even think you need a tune to get the setup you have on the car running properly. But, that is just me. The dyno man appreciates you paying him, so what the heck. Its only money, right?

 

[95BlueStallion]

Im pretty sure that if I were to recalibrate the MAF for 42's I would drown the piss out of my setup. My combo only pushes enough air for 24's. I need a tune to make the computer cut back the fuel. That or just sack up and buy the supercharger and recalibrate the MAF for 42's. But then I need a wideband, and better ignition too...

 

[alleymad95GT]

Nah, I don't think so...

You are drowning it even more by having the undersized MAF. Think about it like this...

A 24# injector puts in some fuel per pulse (keeping it simple, as pressure and duration will affect this as well, but conceptually it will be accurate). Lets say that is amount X.

A 42# injector also puts in some fuel per pulse. Obviously, when the 42# injector pulses, it pulses more than a 24# injector, right? How else would it flow so much more fuel? So, lets say the 42 # flows an amount of fuel equal to X + Y.

Now, X + Y is obviously bigger than X. Of course. Bigger injector.

Now, your 24 # MAF. It gets some air flowing over it. That air flow is translated into a voltage that is sent to the computer. Lets say at some airflow, that voltage is A.

Now, at out hypothetical airflow (whatever it may be), voltage A tells the injector to pulse exactly whatever our hypothetical fuel value X was. Now, what happens if you send the computer voltage A, but you have the 42 # injector in there? Well, the injector pulses X + Y fuel. You see the problem?

A calibrated MAF effectively shifts the curve of the MAF function. The MAF knows how much air your combo is sucking through it. That is its entire purpose. It sends a signal to the computer based on that air flow. Your problem is it is seeing some airflow and sending a signal that will deliver the proper fuel if you had 24 # injectors. You are way rich since the 42 # injectors are so much bigger.

Will the car be the BEST that it possibly can be? No. It will probably be hard as hell to start. Can you get it running really well by prudent adjustments of fuel pressure? You bet. I bet you it will do just fine once it is started.

JMHO, of course...

 

[MysteryMachine]

Do you have the 42's or the 24's in now?


Even with the 42's and 24 cal'd MAF I think it should still start just run like ****

 

[JJ95GTID]

Do you have the 42's or the 24's in now?


Even with the 42's and 24 cal'd MAF I think it should still start just run like ****

I'd have to agree. It should fire even with the mismatch of injector size and MAF.
I've accidently forgot to plug in the MAF and still had the engine start. It just ran rough.

I'd say your timing is off. Try pulling the SPOUT and try to get it to start that way.

 

[MysteryMachine]

Mine ran fine with no MAF LOL