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steveespo new bullet for the 21 Car

steveespo

Lord knows I'm a Voodoo Child
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Yes, That's really good torque, about the same HP (507) but 30 more ft pounds than mine (414) ....How much compression?
Where does all that torque come from? The 200 extra inches or a compression bump or both?
The 14 extra cubes and the stroke. 12:1 compression. I have the Direct Injection which helps torque too but I don't know exactly how much and finally the L&M intake cams do a lot.
 
5,765
6,902
Exp. Type
W2W Racing
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20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
The 14 extra cubes and the stroke. 12:1 compression. I have the Direct Injection which helps torque too but I don't know exactly how much and finally the L&M intake cams do a lot.
I have those same cams and 12-1 so the engines are very similar. I didn't know there was a stock crank with more stroke than the 5.0.
I thought that the rod angle limited the stroke in the Coyotes, at least that's what I was told when I was looking to do a stroker.
That's how I ended up with the stock gen 3 bottom end, it already has 12-1 and I was told there was no more stroke to be had.
The gen 3 also has a couple more cubes than the gen 2 block so I thought I was maxed out.
Regardless it makes great numbers for as little as I spent on it and I spin it to the moon and it lives, still a little more torque would be nice.
 
5,765
6,902
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
The 14 extra cubes and the stroke. 12:1 compression. I have the Direct Injection which helps torque too but I don't know exactly how much and finally the L&M intake cams do a lot.
Whoops...I mean 200 extra cc's....not inches. :rolleyes:
 
Steve has been my Hero since He joined BMO/TMO...The way He transformed His Mustang at the time was amazing and those transformations occur to this day!!!!.....21 is your passion!!!!!!!!!!!.............Enjoy that Passion!!!!!!!!!!!!!!
 
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I have those same cams and 12-1 so the engines are very similar. I didn't know there was a stock crank with more stroke than the 5.0.
I thought that the rod angle limited the stroke in the Coyotes, at least that's what I was told when I was looking to do a stroker.
That's how I ended up with the stock gen 3 bottom end, it already has 12-1 and I was told there was no more stroke to be had.
The gen 3 also has a couple more cubes than the gen 2 block so I thought I was maxed out.
Regardless it makes great numbers for as little as I spent on it and I spin it to the moon and it lives, still a little more torque would be nice.
You need to use a 5.2L GT500 block and crank and order appropriate rods and pistons. Steve and I both used Manley rods and Mahle forged anodized pistons. Like Drew said, spendy (as much as 2.5x the cost of an OEM Gen 3 short block), but it yields a good torque increase. Would be better on E85 or race gas.

My 5.2L makes 410+ torque from 4900 through 5650 with a peak of 427 around 5250. I made a couple of mistakes with the torque above...... HP is 505 peak with 485+ from 6400 through 8,000. It is above 400 from 5,000. I expect Steve's motor to have better results with the direct injection and factory exhaust cam.

The biggest difference between the 5.2 and 5.0 Gen 3 based motors is probably the width of the torque and HP curves - you can get very similar results with the 5.0L, but you need to run E85 or race gas. Again, our engines are conservatively tuned for pump gas (spend more on the initial build, but save a ton on fuel costs).

Maybe a better way of looking at the above is to compare it to my original Boss motor. The motor was the OEM long block with CJ Cams, CJ intake, Ford CJ Cold Air, and Kooks long tubes with off road x-pipe. That motor made a peak of 484 HP and 393 ft/lbs torque on pump gas. So the new motor makes 34 ft/lbs more torque with a broader curve on pump gas.
 
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steveespo

Lord knows I'm a Voodoo Child
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Cookeville TN
I have those same cams and 12-1 so the engines are very similar. I didn't know there was a stock crank with more stroke than the 5.0.
I thought that the rod angle limited the stroke in the Coyotes, at least that's what I was told when I was looking to do a stroker.
That's how I ended up with the stock gen 3 bottom end, it already has 12-1 and I was told there was no more stroke to be had.
The gen 3 also has a couple more cubes than the gen 2 block so I thought I was maxed out.
Regardless it makes great numbers for as little as I spent on it and I spin it to the moon and it lives, still a little more torque would be nice.
It is a 5.2 Cross plane block and crank. Poor mans Aluminator XS builds.
 
5,765
6,902
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
You need to use a 5.2L GT500 block and crank and order appropriate rods and pistons. Steve and I both used Manley rods and Mahle forged anodized pistons. Like Drew said, spendy (as much as 2.5x the cost of an OEM Gen 3 short block), but it yields a good torque increase. Would be better on E85 or race gas.

My 5.2L makes 410+ torque from 4900 through 5650 with a peak of 427 around 5250. I made a couple of mistakes with the torque above...... HP is 505 peak with 485+ from 6400 through 8,000. It is above 400 from 5,000. I expect Steve's motor to have better results with the direct injection and factory exhaust cam.

The biggest difference between the 5.2 and 5.0 Gen 3 based motors is probably the width of the torque and HP curves - you can get very similar results with the 5.0L, but you need to run E85 or race gas. Again, our engines are conservatively tuned for pump gas (spend more on the initial build, but save a ton on fuel costs).

Maybe a better way of looking at the above is to compare it to my original Boss motor. The motor was the OEM long block with CJ Cams, CJ intake, Ford CJ Cold Air, and Kooks long tubes with off road x-pipe. That motor made a peak of 484 HP and 393 ft/lbs torque on pump gas. So the new motor makes 34 ft/lbs more torque with a broader curve on pump gas.
I was initially looking at an aftermarket stroker kit for my gen 2....I was dissuaded from going that route due to the increased rod angle by 2 different prominent engine builders so we did what we did and it worked out well for me. I just didn't realize there was more to be had. Good info for sure. Gen 3 bottom end/gen 2 ported heads. Stock everything w/CJ intake, ARH LT's and L&M cams.

This is what we got:
Dyno 507.jpg
 
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I was initially looking at an aftermarket stroker kit for my gen 2....I was dissuaded from going that route due to the increased rod angle by 2 different prominent engine builders so we did what we did and it worked out well for me. I just didn't realize there was more to be had. Good info for sure. Gen 3 bottom end/gen 2 ported heads. Stock everything w/CJ intake, ARH LT's and L&M cams.

This is what we got:
View attachment 83327
Sal, I will email you my entire Dyno run in the morning. The actual log is in 50 rpm increments, so you should be able to do a detailed comparison. For the money, your build is more cost effective, but probably needs better gas to support a more aggressive tune than what I am running. Unfortunately, there is only one station that may still sell E85 that is not more than a two hour or more round trip to the station where I live….

Do you know what brand Dyno AED uses?
 
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5,765
6,902
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Sal, I will email you my entire Dyno run in the morning. The actual log is in 50 rpm increments, so you should be able to do a detailed comparison. For the money, your build is more cost effective, but probably needs better gas to support a more aggressive tune than what I am running. Unfortunately, there is only one station that may still sell E85 that is not more than a two hour or more round trip to the station where I live….

Do you know what brand Dyno AED uses?
Dyno comp.
I was just interested in the torque curve. I’ve seen some builds with high peak power over a fairly narrow power band. the logic of this build was to have a little less peak power but a more broad power band. It seems to work well but I really have no idea how it compares to other combinations. Just trying to learn something Here.
 
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5.2L Chart with ignition timing limited to a max of 23 degrees (i.e. less than OEM non-track key Boss timing limit)

1674742675574.png

5.2L vs. Boss Long Block with CJ Cams, CJ Intake, CJ cold air, twin 65mm throttle body, long tubes, off road x-pipe (same dyno, different days):

1674742790690.png
 

Bill Pemberton

0ld Ford Automotive Racing Terror
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JeffV8,

Just curious if you have checked either of the E85 stations for their percentages. I live in the " Land of E85 " and we see big differences station to station. My son actually wanders over to Council Bluffs , Iowa ( just across the Missouri River ) from the Omaha area because a station there is almost always over 90%. Just a thought, as there can be differences out there.
 

Doublewing

2018 gt350
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Staten Island
Finally getting around to assembling my 5.2 build to install in the 21 Car early this season. Starting with all new parts sourced mostly through Capaldi Racing, including Mahle pistons/Manley forged rods with ARP2000 bolts, cross plane 5.2 FP350 crank, predator block, Gen 3 Coyote heads with PAC 1281X valvesprings and Titanium retainers, ARP head studs and damper boltView attachment 82887View attachment 82888View attachment 82889View attachment 82890View attachment 82891View attachment 82892View attachment 82893View attachment 82894View attachment 82895View attachment 82896View attachment 82897View attachment 82898 . Shortblock was deburred, honed, cleaned, sized, balanced and assembled by Holbrook Racing. All accessories are new such as fasteners, oil pan/pump is GT500, timing kit is Gen 3 new from Ford Performance with Boss 302 primary tensioners, GT500 water pump, ATi Damper and all new sensors, front cover and cam covers. Assembly is going well and here are some pics of the progress, should be ready to swap in about a week as I am waiting on a few specialty tools to install rear seal and the Direct Injector seals.

I haven't made a new post in a while so I thought I would share.
Steve
Keeping busy after retirement love it there is a light at the end of the tunnel
 
JeffV8,

Just curious if you have checked either of the E85 stations for their percentages. I live in the " Land of E85 " and we see big differences station to station. My son actually wanders over to Council Bluffs , Iowa ( just across the Missouri River ) from the Omaha area because a station there is almost always over 90%. Just a thought, as there can be differences out there.
It’s usually around 87% . 2 different stations but same results.
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
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Cookeville TN
A couple more details out of the way today. DI Injectors and piping plus the oil outlet adapter fitted. Slight mismatch on both the outlet and inlet sides of the adapter so I did a little port matching on the adapter to blend the flow in. Easier to clean the aluminum adapter than ensuring no particles get into the block.e13.jpge14.jpg
 
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A couple more details out of the way today. DI Injectors and piping plus the oil outlet adapter fitted. Slight mismatch on both the outlet and inlet sides of the adapter so I did a little port matching on the adapter to blend the flow in. Easier to clean the aluminum adapter than ensuring no particles get into the block.
For everyone's SA, we have only seen the port mismatch using the Ford Performance remote filter adapter on a Gen 3 block. For those needing to put this in an earlier car, the GEN 2 filter adapter ports line up correctly. Also, the ports on the Improved Racing filter relocation adapter line up, but the angles for the line attachments on the block are not as good as the Ford adapter in some instaces and the placement of the oil pressure sensor port for the OEM low oil pressure sensor causes a clearance issue with the alternator unless you use a 45 degree elbow.
 
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Did you need to buy a specialty tool for the direct injection o-ring and injector installation? I know you mentioned that their was a detailed procedure for the installation.
 

ArizonaBOSS

Because racecar.
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Really good info here, I hadn't thought about doing the Predator "shortblock" combined with G3 heads as a combo before. This *has* to be less money than an Aluminator XS5.2 (almost anything would be less expensive than that, though).

@steveespo @2012-Boss what are you guys doing for engine management? Gen3 controls packs?
 

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