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-   -   Adding AFR185's to FMS392 (http://www.clubcobra.com/forums/small-block-talk/70106-adding-afr185s-fms392.html)

69 Mach I 08-08-2006 08:03 AM

Quote:

Originally Posted by Mark Brye
Well, I ordered the 185's with 58cc chambers. I took the car to the local DynoJet to get a baseline. It sure didnt make what I expected granted I had done no tuning to the car as I received it from Backdraft. I don't even want to post the numbers but I figure this will be a help to someone somehow.
302HP and 323tq. Horsepower flattened out at 5300rpm. My air fuel ratio was between 10-11 so its WAY rich as delivered by backdraft. We checked the timing and it was at 8 initial. So either I have a really bad 392 or I am loosing about 70 due to a super bad tune. Will let everyone know what my new numbers are in a week or so after the head swap. Dyno sure is the ultimate ego deflater!:3DSMILE:

Also got car weighed. 2540 with 1/4 tank of juice

what transmission do you have?

What cam is in there?

Mark Brye 08-08-2006 08:12 PM

I think Ford uses the Comp Cam XE282HR which is 566/576 232/240 if memory serves me correctly. I was thinking about using more cam also but not sure how big I can go with just the 185 heads

Mark Brye 08-08-2006 08:17 PM

Oh, it also has a Tremec TKO600 for a tranny

69 Mach I 08-09-2006 03:53 AM

Quote:

Originally Posted by Mark Brye
I think Ford uses the Comp Cam XE282HR which is 566/576 232/240 if memory serves me correctly. I was thinking about using more cam also but not sure how big I can go with just the 185 heads

Oh, it also has a Tremec TKO600 for a tranny

You have plenty cam. Increasing your duration will only shift your power band to the right (read "up") in terms of RPMs. You should have way more RWHP for a TKO. I estimate that the TKO eats at most 15% of your power so your fly wheel hp is about 355. My 351W makes 316 rwhp behind a C6 auto tranny, which eats about 22% of your power. This gives me about 405 hp. You should be making not less than 430 hp (maybe more with those heads, prolly 450 hp) with that engine, which would be 365 hp or more at the wheels. Something is wrong. Could be timing, could be carb, could be something else.

Mark Brye 08-14-2006 07:39 PM

Well, I do not have enough piston to valve clearance on the intake valves. So it looks like I am going to have to flycut the pistons. Is this possible while in the car? The person doing the work says he can use the head and use a valve cutting tool to make the valve releifs a little deeper. I guess the stock pistons have a 2.02 releif its just the depth is not enough. I knew this head swap would not be just like in the mags! Oh well. I wonder how much this will throw off the factory engine balance....At least I really trust the installer.

Blittleton 08-14-2006 08:53 PM

Mark,

That is a Ford crate motor for you. You should have stuck with us and bought a motor. 393 with AFR 205's.

Bill

Mark Brye 08-14-2006 09:07 PM

Yep! Thats for shur! Actually, I have a guy here at work that is looking at BDR's. I told him all about you and how you had been so kind to come pick me up at the airport and everything. His name is Clarence and will be giving you a call.
Once again, a person gets what they pay for. See how much I saved buy buying a ford crate motor :)

Take care Bill;)

bignoze 08-15-2006 07:56 AM

Mark,

Something is not right, others on this board have done the AFR 185 replacement with plenty of valve clearence. I think you need to double check?

Mike

Cashburn 08-15-2006 09:40 AM

Mark,
Did you take into account the thickness of the head gasket? There are some thicker gaskets out there.....

Are you running the same ratio rocker? 1.6

Also as far as your baseline #'s. Are they SAE corrected or not? And if not you have to take into account humidity, temperature, altitude etc. in order to be able to compare to anything else in the country or even dynoing on a different day. Some tuners also like to change the correction factor to a high # to make you feel better, so watch out for that when people post results. See it all the time...

Properly tuned FMS392 should do 350-360 RWHP in a BDR with a TKO5/600. What was or is your total timing? Dont worry about baseline.
Also get your A/F to about a 12.8 average at WOT with a N/A motor.
There was easily 40 hp in tuning in that car in my guestimation.....

bignoze 08-15-2006 12:37 PM

And in the one of the mag articles they had the head cambers milled down to 54cc which would put the clearence even less and they did not cut the pistons. Something not right?

Mark Brye 08-15-2006 12:41 PM

We used 1.6 ratio rockers and reused the gaskets that had already been compressed from the X heads for taking measurements. What we came up with was .05 (.04-.06 for all eight pistons) clearance on the intake valve. We measured each intake valve several times because we couldnt beleive we had a problem. Only thing I can figure is that because my engine is a 2006 model, the forged pistons do not have the releif in the pistons as deep as the hypertectic pistons. Also measured with the old X head installed and came up with about .08 on the intake (I think).

bignoze 08-19-2006 02:09 PM

Mark,

Did you try calling the Ford MotorSports hotline or AFR helpdesk?

Mike

Mark Brye 08-19-2006 06:04 PM

I talked to Ford Tech line. When Ford switched to the forged pistons, they lost some of the valve releif. The piston that Ford is using is made by Probe Industries. Tech line said this is the same shortblock that is used with the 475 HP 2.02 Z head. According to the tech they often do not have P/V clearance with the Z head on the motor with the forged pistons.
Anyway, I will let everyone know how this turns out.

tbirdz12 08-21-2006 06:42 PM

im sure you seen this reprint on the 185s with the 392.
http://airflowresearch.com/articles/...024/A24-P1.htm
Looks like its a 535 hp/505 Tq setup.


That is the exact combo in my car, 'cept i have an RPM Air Gap with the 750 demon.

Its a very nice setup, 'course you always want more.

tim

Mark Brye 08-30-2006 09:07 PM

Thought I would give everyone an update. The engine is still torn apart. The new forged pistons that Ford is using in the crate engine are a real pain. The valve releifs are not centered perfectly for an AFR head even though they have 2.02/1.60 releifs. Ended up making deeper releifs in both the intake and exhaust. And let me tell you, forged pistons are really hard to cut releifs into. Practiced on an old engine before going to the crate motor and the non forged pistons are alot easier to notch. Some other issues we ran into are that you have to do research on which rocker arms that are used. I ordered Comp Pro Magnum rockers for stud mount 7/16 and the trunion of the rockers will not clear the valve springs. This is even with the longer studs that AFR said you have to use. So I ordered and tried Probe rockers (did not work) and then TFS rockers and they work. When we got the motor back together and filled it with coolant, we had a leak on the back of the head. Turns out the new Ford Racing Sportsman block has revised water passages so the Felpro 1011-2 head gaskets don't cover the water jacks perfecly. So the engine came back apart. I hope the new gaskets will work. Oh, and when I see "we", I am referring to my buddy who is doing all the work. What a great sport he is! I really owe him won.

Cashburn 08-30-2006 09:50 PM

Mark,
Thanks for the updates. This is important info. Sorry you have to be the first to find this out. Perhaps Ford needs to understand how important that article was to their current and future customers who buy-in with the intent of building it out later? Nope, that would be too much forward thinking...

bignoze 08-31-2006 02:47 PM

Mark,

Thanks for the updates as this is a mod I plan to do next year and I am now glad I have the older FMS 392.

Mike

jmac5032 09-03-2006 06:24 PM

So what increase in jetting are you guys typically seeing on the increase from the old heads to the AFR 185's? 75 more HP is a bunch more.

Mark Brye 10-01-2006 05:37 PM

Hi everyone,

I have received alot of emails asking for an update on my head swap dyno results. I have been on travel for the last couple of weeks and the dyno shop I used had recently relocated so there dyno had been down. I hope to get the car dyno'd soon now that they have the dyno up and running again. I will post the results once I have the car tuned.
On a side note, I can say that these heads have made a big improvement. I can sure feel it in the seat of the pants. I can't wait to see what a tune does!

Mark Brye 10-08-2006 09:41 AM

Made it back to the dyno today. Original numbers with Xhead 302hp,323tq as delivered from BDR. This had 10-11 air fuel ratio. After only the head swap to AFR185's and no tune, numbers increased to 383hp, 375tq. The air fuel ration leaned out to the 11-12 range. After making about 10 pulls, and playing with timing and jets, I am at 415hp, 415tq.
One thing we did notice, is that my fuel pump is getting near its limits. It has a Carter Electric pump with a gold top. I have tried to find information on it but have not found it anywhere to see what its capacity is.


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