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Removing heads with engine in car


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Tony-Muscle,

If you are going to pull rocker covers, I would suggest you re-check your valve timing.

Comp cams offers a method  called lift@ TDC no degree wheel required.

You WILL have to know where true tdc is on your balancer, find your grind # , in your case 3354s int. and 3355s exh. and look them up in your comp master catalog, it will state your lift @ tdc for each lobe in inches, then you put your dial indicator on the lifter or pushrod to read and see if all adds up.

Google , comp cams lift @ tdc, Prestige motorsports has a great video on this subject.

FWIW our cam specs are nearly identical but I had comp build me a reduced base circle bumpstick and I run more compression ratio.

 

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3 hours ago, boilermaster said:

Tony-Muscle,

If you are going to pull rocker covers, I would suggest you re-check your valve timing.

Comp cams offers a method  called lift@ TDC no degree wheel required.

You WILL have to know where true tdc is on your balancer, find your grind # , in your case 3354s int. and 3355s exh. and look them up in your comp master catalog, it will state your lift @ tdc for each lobe in inches, then you put your dial indicator on the lifter or pushrod to read and see if all adds up.

Google , comp cams lift @ tdc, Prestige motorsports has a great video on this subject.

FWIW our cam specs are nearly identical but I had comp build me a reduced base circle bumpstick and I run more compression ratio.

 

Thanks. When I installed my cam I did the whole degreeing thing. Everything was within 1 degree.  I will research the method you are talking about to double check though.

Do you have a dyno run or time slip with this cam? What is your CR? I would like to have more CR so I if I end up removing the head I am thinking of a thinner head gasket. The problem is that the only thinner gaskets out there are MLS which I think they could have issues with sealing if the surfaces are not well preped. Mine was resurfaced when I stroked it so it may work.

20210826_100810-mod-s.jpg.52aeaedc03b0419348700fb9c465e338.jpg

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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I am not sure if you got an answer to your original question.   I have pulled and in stalled the heads from my 351C  4v that has ARP studs in my 73 convertible.

 

 

'Mike'

73 Convertible - 351C/4V CC heads/4bolt/forged flat tops/comp 270/rhodes/mallory unilite/tri-power/hookers/glasspacks/c6/3.50 limited slip/Gear Vendors/Global West sub frames, strut rods and shelby style traction bars/ Rear sway bar/tilt steering (not original)

 

Pics of modifications included in: [button=http://www.7173mustangs.com/thread-1973-convertible--3335]My Garage[/button]

 

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28 minutes ago, will e said:

I am not sure if you got an answer to your original question.   I have pulled and in stalled the heads from my 351C  4v that has ARP studs in my 73 convertible.

 

 

Thank you. This is great to know. I am sure that it was fun lifting those anchors while leaning over the fender.

20210826_100810-mod-s.jpg.52aeaedc03b0419348700fb9c465e338.jpg

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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On 9/15/2021 at 10:44 AM, tony-muscle said:

Thank you for raising all very important points. Yes, in one way I ask myself, is it worth it to gain maybe 20 more HP? I also tell myself, if ain't broken don't mess with it. On the other end, I tell myself, you should have done this when you assembled the engine? And then I ask myself, if I can gain some performance with little monetary investment, why not? All these things are going though my head. If I can remove the heads in the car I don't think it is that much work specially over the long winter months where I have the luxury of many months of not using the car. It is also true that by shrouding you incrase the chamber size and so the CR goes down. However, I don't expect shrouding to be more than 1cc, probably less, which will reduce CR by 0.1. Also, I think the most gains are from shrouding the intake only so that way you can reduce the amount of material removed. An alternative is to search for thinner gaskets to compensate.

In any case, here is a recent chassis dyno sheet, which I think I have not yet published. Let's not focus too much on the numbers, but look at how the power is dying after 4,500-5,000 rpm. I understand that my cam lift is not that much but I was not expecting it to die off so early. This is one of the reasons why I think I should be able to gain some power by increasing flow by shrouding the intake valve. From my research most of the flow gains are below 0.600 lift, which is where my cam is. Yes, it is possible that I am being hopeful, but there is that hot rod mentality that pushes me to improve if within the possibilities. If not the heads, for sure I will be removing the valve covers to check that everything is good with the valvetrain. 

 

Dyno day at HRPT2021.jpg

 

Look at @73' mach 1 dyno run for comparison. He has a very similar setup except that he has a cam with slightly more lift and some minor heads porting.

Edit: notice also how the torque numbers are very similar between the two engines but my fall from the sky at about 4,500 rpm.

79518.jpeg.59ae3d7afbeb04bbbe5f33979d4682aa.jpeg.6570e079eb52bbc24bf9a0a325818b76.jpeg

 

Also just to add that my heads are 4V open chambered. I believe it was @Don C that mentioned how oc heads flow better on a stroker.

www.puregemdetailing.com

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73'mach1,

10 years ago, I would have called Don's statement rubbish, but the fact is it's very true (at least where our iron heads are concerned.

Pretty sure this all came about when the MoCo started dropping compression ratios and then everyone thought compression ratio was the ONLY way to build power, blame it all on the Boss and its (advertised compression ratio and horsepower).

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2 minutes ago, boilermaster said:

73'mach1,

10 years ago, I would have called Don's statement rubbish, but the fact is it's very true (at least where our iron heads are concerned.

Pretty sure this all came about when the MoCo started dropping compression ratios and then everyone thought compression ratio was the ONLY way to build power, blame it all on the Boss and its (advertised compression ratio and horsepower).

I'm a believer.  I was so worried I was going to be disappointed in the numbers my 408 would make with those heads. Love telling people the power she made on stock oc heads!

www.puregemdetailing.com

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I have seen some people go totally nuts trying to figure out all types of issues with their engines that have the Holley Sniper/FiTech fuel injection system. I was following a guy on YouTube that was going completely nuts with a drivability issue with his Holley Sniper. After months of frustration he finally figured that that the issue is RFI/EMI noise. I know that it sounds nuts, but these old cars were never designed to run EFI, and thus have little to no RFI/EMI suppression on their electrical systems. The RFI/EMI could be so bad that the EFI system just does not run, or it could be mild and you get power/drivability issues. Worth taking a look at it. Search YouTube for "Holley Sniper RFI problems or FiTech RFI problems. You will find a ton of issues. This is a generic video of the issue, buy it will give you an overview of what can happen:

Everything that I can see on your engine specs looks right. Cam was degreed in, springs were installed at the correct height, you have checked your compression and know exactly what it is etc... I would not even think of pulling those heads to do a little valve unshrouding or porting, the difference will be negligible. This seems like a tuning issue, either ignition or fuel. I doubt that you have any valve float issues, valve float is very noticeable, and when you hit valve float the engine just hits a wall. Also once you start floating valves, the floating will start earlier and earlier as the springs get fatigued by the valve float.  There are 2 dips in that Dyno chart after 5000 RPM, which should not be there. Do you have a way to check your fuel pressure to make sure that it is not somehow falling off at higher RPM? Maybe the timing is doing something strange after 5000. If I were to take a guess , I would bet on fuel delivery, but I could be very wrong. 

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1 hour ago, 71ProjectJunk said:

I have seen some people go totally nuts trying to figure out all types of issues with their engines that have the Holley Sniper/FiTech fuel injection system. I was following a guy on YouTube that was going completely nuts with a drivability issue with his Holley Sniper. After months of frustration he finally figured that that the issue is RFI/EMI noise. I know that it sounds nuts, but these old cars were never designed to run EFI, and thus have little to no RFI/EMI suppression on their electrical systems. The RFI/EMI could be so bad that the EFI system just does not run, or it could be mild and you get power/drivability issues. Worth taking a look at it. Search YouTube for "Holley Sniper RFI problems or FiTech RFI problems. You will find a ton of issues. This is a generic video of the issue, buy it will give you an overview of what can happen:

Everything that I can see on your engine specs looks right. Cam was degreed in, springs were installed at the correct height, you have checked your compression and know exactly what it is etc... I would not even think of pulling those heads to do a little valve unshrouding or porting, the difference will be negligible. This seems like a tuning issue, either ignition or fuel. I doubt that you have any valve float issues, valve float is very noticeable, and when you hit valve float the engine just hits a wall. Also once you start floating valves, the floating will start earlier and earlier as the springs get fatigued by the valve float.  There are 2 dips in that Dyno chart after 5000 RPM, which should not be there. Do you have a way to check your fuel pressure to make sure that it is not somehow falling off at higher RPM? Maybe the timing is doing something strange after 5000. If I were to take a guess , I would bet on fuel delivery, but I could be very wrong. 

If it were fuel delivery I should see a lean condition in the AFR logs. Right now I don't see any lean condition. It was actually running too rich at around 11.9 at 6,000. Now I have it set leaner at 12.8. A few years ago I was chasing some other issues at idle and have my EFI very well RFI isolated. I am not running EFI timing, just a good 'ol distributor with all in at 36 degrees.

 

 

Edited by tony-muscle

20210826_100810-mod-s.jpg.52aeaedc03b0419348700fb9c465e338.jpg

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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2 hours ago, boilermaster said:

73'mach1,

10 years ago, I would have called Don's statement rubbish, but the fact is it's very true (at least where our iron heads are concerned.

Pretty sure this all came about when the MoCo started dropping compression ratios and then everyone thought compression ratio was the ONLY way to build power, blame it all on the Boss and its (advertised compression ratio and horsepower).

I have CC 4V heads so I have to work around what I got.

20210826_100810-mod-s.jpg.52aeaedc03b0419348700fb9c465e338.jpg

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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  • 1 month later...

I wanted to circle back to this post to provide closure.

The answer to the original question is yes, you can remove the heads with engine in car. After reading some of the suggestions I had the typical fender cover, then a carboard box and then a roof rack pad to distribute the load along the fender instead of one location. The fender did no get damage. I was able to do it with the studs in but it is very tight on the driver side due to the master cylinder. The heads are so heavy that it is difficult to move them on that side and it is difficult to get a good grasp (A/C hose and power steering hose also in the area). With all that I was successful. I recommend that if you have studs, to remove them. It is very easy. To be honest, I have no idea why I didn't remove them but I was just trying to prove if it can be done with the studs on. In any case, it takes a lot of arm strength and patience removing all the stuff that's in the way.

You can read more about it in here: https://7173mustangs.com/forums/topic/39677-muscletang-engine-shows-a-smooshed-spark-plug/#comment-398206

In regards to the loss of power mentioned in here, it is clear that my issue was a smooshed spark plug electrode that was rendering one cylinder useless or close to useless. With that, the dyno results shown here were with 7 cylinders so I am confident it would have looked a lot better with all 8 cylinder firing! Now, since the heads are already out, they will undergo some porting anyways.

 

 

Edited by tony-muscle

20210826_100810-mod-s.jpg.52aeaedc03b0419348700fb9c465e338.jpg

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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