Stroker motor talk!-Threads merged

[Agui-E7TE]

It's also worth mentioning that factory cats seem to work better than the cheap aftermarket cats.

As far as headers, I would recommend shorty equal length headers from BBK (they're the 1 5/8-inch ones) or the summit racing headers or BBK shorty headers (unequal length) if you're on a budget. Long tube headers might not really be worth the hassle since you might have to factor in driveline interference on the front shaft.

I have BBK 1 5/8-inch shorty headers on my '91 Mustang notchback and it's pushing enough power to keep up with a supercharged 2012 Mustang Shelby GT500 so I don't think the benefit of long tube headers will make a big difference on a truck that weighs possibly twice as much as my Mustang. Shorties work great and you don't have to worry about packaging modifications to get everything to work.

[Rmc]

Speaking of mustangs, has anyone done a mustang full engine swap into a bronc? I know there's block differences, but there's a lot more available hop ups for them. It might be cheaper to do a conversion to get to my desired 400 hp than a stroker motor n still be ok on smog.

[hobbyturnedobsession]

I dont think u can

[philofab]

Speaking of mustangs, has anyone done a mustang full engine swap into a bronc? I know there's block differences, but there's a lot more available hop ups for them. It might be cheaper to do a conversion to get to my desired 400 hp than a stroker motor n still be ok on smog.

Other than the Cobra motor, they have the same heads. The intake is different but there is no reason you couldn't swap one in.

I know of a few that have swapped GT40 Explorer engines in without issue. They retained the factory intake and computer.

[AussieRod]

I'll assume you want more torque and HP for your Bronco, so may I suggest you upgrade to a 5.8L engine? The money you will spend to turn a 5.0L to a 5.7L (347) will more than pay for a good 5.8L and some mods to improve it. If you have to smog test, a 347 with 5.4"rods will fail smog because the wrist pin intrudes into the oil ring groove, resulting in oil passing into the intake charge and creating higher emmisions. A 5.8L does not have this problem, so might I suggest this:
a good 94+ roller block 5.8L in good condition (+25hp & 35 lbs/ft)
fit the 5.0 HO hyd. roller cam, lifters and spider w/ bolt-on 1.7 roller rockers (15 - 20 hp)
EO approved aluminum heads and Edelbrock intake w/ stock TB (easy 25 - 50 hp bolt-on)
EO approved headers, and use your factory Y pipe only for smog testing, and build a hi-flow Y with a large metal substrate cat for normal use.

To fit the 5.8L, you need a longer serp belt, a different flex plate (5.0 50 oz v 5.8 28 oz balance) and a different Y pipe. This is just my opinion, but you WILL have MORE TORQUE, the main requirement to move your heavy Bronco along, better drivability and better fuel consumption ( if you can stay out of the loud pedal) and it will look almost stock under the hood, besides being smog friendly, too.

[Rmc]

Thx a lot Aussie, ya that's the kind of answers i am looking for. As of now I'm researching the compatibility of all my 302 goodies. The heads are world roush 200's and the e303 is a roller cam, those will work on a 351 after i drill out the head bolt holes. I'm thinking the push rods will go in the trash but I need to find out out if my rockers are stock, 1.5,6,7 ect. I bought all these parts over 5 years ago and there currently on another 302 that I have 90 percent complete. But the bottom end has 116k on it. I'm wondering if I should just swap long blocks n accessories. But from the reading I'm doing it looks like the heads n cam are compatible. I'm thinking I need to find a 94+ maf 351 complete from oil pan to tb. Then I think ill take it to my friends machine shop n have him go thru it. Stock would be the same effect as my stroker, and with the heads( so long as not too much has been flycut off them) I agree I would be way better off n smog should be no prob.

[Rmc]

I'm glad u mentioned the flex plates, I was unaware of that issue as this will be my first 302 to 351 swap. I think everything but the knock sensor is the same, and I may need to put a larger tb on it but that seems to be no big deal. Next I need to figure out the knock sensor delete or if its even necissary. I read the 351 out of an f150 doesn't have a knock sensor. I wonder if I got a 94 bronco 351 if it would have a knock sensor same as the 302. I have to do more research. Appreciate the input from all u guys.

[hobbyturnedobsession]

As far as im aware they do not have a knock sensor in 94.

[Rmc]

Honestly I'm not really shure, chiltons guides are rough, kinda sorta ball park if u don't have or do have this or that option. The book is ok for the numbers but that's about it in most cases. I've learned more from the web than anything. I need to get my hands on a factory wiring diagram next I think.

[hobbyturnedobsession]

My long block 351 roller was from a 94 or 95 and it didnt have a spot for the knock sensor.

[Rmc]

Was it an f150? Mustang? The whole knock sensor thing was from a mustang article I was reading. I'm not shure on mine, I'm changing the oil tomarrow so ill have a look. With the obd1's I can't remember, I usually gutted em n threw a carb n msd box in the past.

[hobbyturnedobsession]

My 351 was from a bronco / f150. Obd1 or at least mine doesnt have a knock sensor.

[AussieRod]

I'm glad u mentioned the flex plates, I was unaware of that issue as this will be my first 302 to 351 swap. I think everything but the knock sensor is the same, and I may need to put a larger tb on it but that seems to be no big deal. Next I need to figure out the knock sensor delete or if its even necissary. I read the 351 out of an f150 doesn't have a knock sensor. I wonder if I got a 94 bronco 351 if it would have a knock sensor same as the 302. I have to do more research. Appreciate the input from all u guys.

The stock truck TB flows slightly better than a 75mm single blade Mustang TB, the main "cork" in the intake on the 5.8L is the manifold itself. I'm sure if you swap all the 5.0L sensors over to the 5.8L, everything will work ok. Keep in mind, you may still need a custom tune to make sure the ECU will work properly with your engine mods. Much more than the mods I suggested will require bigger injectors and a custom tune, to the detrament of the smog test. Dont go overboard if smog is an issue. Everything in moderation will give you less headaches later trying to sort out tuning issues

[philofab]

The knock sensor will work just about anywhere... however the most accurate spot is in the center of the intake valley.

Since our truck run the hottest / leanest on the rear cylinders I would find a coolant passage towards the rear to install it on. You could also drill and tap a hole.

[Seattle FSB]

Here is the poop on the 5.0L Knock Sensor:


The Knock Sensor is a signal generating device called an accelerometer. It detects engine detonation (knocking), and converts this frequency signal in a voltage. The sensor consists of a piezoelectric element mounted in a threaded metal housing. Vibrating the element generates the voltage signal. Special construction makes the element only sensitive to the particular engine vibrations associated with knocking.

When spark knock occurs, the Knock Sensor produces a pulsing electrical signal. This signal is put through an amplifier and then sent to the EEC. The EEC then immediately retards spark timing until knock is no longer sensed, or up to a maximum 8° retard. The engine will return to normal spark advance after the MAP sensor detects a 3-4 in. Hg. change in engine vacuum.

In summary, the Knock Sensor assists the 5.0L PCM in allowing the timing to be advanced to the edge of detonation and then backs it off slightly for maximum performance and fuel economy.


Ryan McCormick from RJM Injection Technologies offers the following 5.8L perspective:

Why doesn't the 351 have a Knock Sensor?

1. 5.8L is a stronger block.
2. 5.8L has a better firing order than a standard 5.0L from the 1980's.
3. MAF does a better job of calculating fuel ratios, which helps prevent lean conditions.
4. It saved Ford some money by not including 1 of everything found on their parts self.
5. Not all engine designs have a frequency that is easily identified as a "knock" from the other valve train background noises.

Keep in mind that a 5.0L is a different beast having smaller mass, operates at higher rpm’s and has different harmonics which a Knock Sensor can identify.

[baja-chris]

I've heard of shock bypass valves falsely triggering the knock sensor.

[ESHALLBETTER]

I've heard of shock bypass valves falsely triggering the knock sensor.

That's awesome...I mean it would suck, but it's awesome.

[BajaBen]

Starting to do my research, pulled my motor yesterday. Its build time, my buddy says to make the 351 into a 408. I was looking at the SCAT assemlbly on Jegs for $1320.00, my block is good according to my machine guy.

In my 95 Bronco, can I use the Scat 408 assembly kit and be trouble free ? Am I going to run into tuning or other issues ?

Plan as of right now is to,
rebuild it to 408
stock heads (rebuilt)
RV cam (still researching)
stock intake
shorty headers
keeping the EFI, smog stuff

thanks

[TurboJoe]

Starting to do my research, pulled my motor yesterday. Its build time, my buddy says to make the 351 into a 408. I was looking at the SCAT assemlbly on Jegs for $1320.00, my block is good according to my machine guy.

In my 95 Bronco, can I use the Scat 408 assembly kit and be trouble free ? Am I going to run into tuning or other issues ?

Plan as of right now is to,
rebuild it to 408
stock heads (rebuilt)
RV cam (still researching)
stock intake
shorty headers
keeping the EFI, smog stuff

thanks

Just keep an eye on your compression ratio ( keep close to stock ) if its early 95 you will most likely need a tune if its speed density... If its mass air you could probably get away with an adjustable fuel pressure regulator. A friend years ago did this in a 92, 10.5:1 big comp cam and it was a tuning disaster ( pinged at idle, stumble on rev And bogged until 4500rpm then started pinging again ) Registered in A/Z put a carb on it and made 430ish to the ground through a C6.

Hope this helps,
Joe

[Seabass]

Starting to do my research, pulled my motor yesterday. Its build time, my buddy says to make the 351 into a 408. I was looking at the SCAT assemlbly on Jegs for $1320.00, my block is good according to my machine guy.

In my 95 Bronco, can I use the Scat 408 assembly kit and be trouble free ? Am I going to run into tuning or other issues ?

Plan as of right now is to,
rebuild it to 408
stock heads (rebuilt)
RV cam (still researching)
stock intake
shorty headers
keeping the EFI, smog stuff

thanks

Ben, factory heads will suck on a 408. Pony up for better flowing heads