is there a head direct fit that cn replace turbo head

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intimidatorj
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is there a head direct fit that cn replace turbo head

Post by intimidatorj » Fri Jan 01, 2016 1:59 pm

okay guys i bought my 87 xr back in june been stoked about fixing have finaally got the head off ato reaplce the blown heaad gsket. well took it (hed) to get a valve job done ,shaved, and pressure checked well found out the gasket wsnt the only thing wrong i have a crack from intake side down to a water jacket and i CANNNOT find nother turbo head wondering if you can get the n/a head swap valves and valve seats out nd use it or is there any other options out there ????

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Re: is there a head direct fit that cn replace turbo head

Post by Choochoochoo » Fri Jan 01, 2016 3:42 pm

From what Ive read on stinger-performance.com, you can use a n/a head with the turbo setup. They suggest that you "port the chambers so that it more closely resembles the stock turbo head's "D" shaped chambers". They also suggest upgrading the exhaust valves, and getting hardened valve seats installed.. If it were me, I'd just try to get as much head work done as possible (funds allowing) and then install it. That way you don't have to remove the head a second time to do more work..
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Re: is there a head direct fit that cn replace turbo head

Post by James Wieler » Sat Jan 02, 2016 11:18 am

I have ported and polished 4 turbo and one NA head this past year. The turbo and NA heads were exactly the same in every way except for the combustion chambers. The NA head had a peak between the valves. This was easily removed with a 1/2" carbide cutter (flame shaped). See my videos:
https://www.youtube.com/watch?v=Ustx9v_Iq04

My channel has several head porting/polishing videos you might be interested in.
https://www.youtube.com/channel/UCIy4vT ... hErvHmxWLw

Given the scarcity of un-cracked turbo heads we should all be looking for NA heads for our cars. There is a myth out there that the NA heads are completely different, which is total nonsense.
James
T3/T40E-50 trim, 3" exh, FMIC, gutted/rotated upper, ported lower intake,60mm T'body,big valves,big VAM,LA3,1990 5.0L WC T5 0.82 5th gear, Cossy sway bar, Powerflex, Dynalites, Focus SVT rotors,Koni yellow sleeve over 8"x300lb/in springs,Scorch bumper cover, 17x7.5x40mm Binno wheels, 225/45-17 Kumho 712 tires

intimidatorj
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Re: is there a head direct fit that cn replace turbo head

Post by intimidatorj » Mon Jan 04, 2016 4:18 pm

So all that needs to be done to the n/a head is to take the peak out in between the valves ? do I not need to have the intake ports ported to the d shape ?

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Re: is there a head direct fit that cn replace turbo head

Post by James Wieler » Mon Jan 04, 2016 5:55 pm

I have not done an exhaustive search of NA heads so there might be some different versions out there. There is a dual plug head which could have different port shapes but I'm not sure. The NA head that I have looks identical in every way except for the "peak" in the combustion chamber. Before you buy, get lots of picks and post them here and compare to your turbo head. It should be pretty easy to make the comparison.
I was going to use the NA head on my turbo but during the porting and polishing process I broke through into a water jacket (ruined), the head I have now is from a turbo.
Before you spend any money on a new head have it magnafluxed for cracks. Turbo heads typically crack at the exhaust valve seat or between the two valve seats. My local shop charges ~$40 to clean and magnaflux.
T3/T40E-50 trim, 3" exh, FMIC, gutted/rotated upper, ported lower intake,60mm T'body,big valves,big VAM,LA3,1990 5.0L WC T5 0.82 5th gear, Cossy sway bar, Powerflex, Dynalites, Focus SVT rotors,Koni yellow sleeve over 8"x300lb/in springs,Scorch bumper cover, 17x7.5x40mm Binno wheels, 225/45-17 Kumho 712 tires

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Re: is there a head direct fit that cn replace turbo head

Post by DPDISXR4Ti » Tue Jan 05, 2016 11:48 am

There are several different N/A heads; only one, from the 70's, has intake ports which match up to the Turbo head. Several of us have used the Dual-Plug head but that requires a lot of other stuff to come along with it including the intake manifold and conversion to DIS.
Brad

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Re: is there a head direct fit that cn replace turbo head

Post by intimidatorj » Tue Jan 05, 2016 2:10 pm

Well I got to looking at my head (87 xr) today and noticed the cubs room chamber where the valves sit that it's heart shaped versus the D shape dose the tell me that the head has been replaced be fore with a N/A head ?

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Re: is there a head direct fit that cn replace turbo head

Post by DPDISXR4Ti » Tue Jan 05, 2016 2:34 pm

intimidatorj wrote:Well I got to looking at my head (87 xr) today and noticed the cubs room chamber where the valves sit that it's heart shaped versus the D shape dose the tell me that the head has been replaced be fore with a N/A head ?
Yes.
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Re: is there a head direct fit that cn replace turbo head

Post by intimidatorj » Tue Jan 05, 2016 5:20 pm

Thanks brad !!!! No wonder it cracked so severely

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Re: is there a head direct fit that cn replace turbo head

Post by James Wieler » Tue Jan 05, 2016 6:20 pm

I don't think it cracked because it was from an NA car as the casting and general construction of NA and turbo heads appear to be very similar. It likely cracked because that is what these heads do and turbos are likely more prone to cracking simply because of the increased exhaust heat.
T3/T40E-50 trim, 3" exh, FMIC, gutted/rotated upper, ported lower intake,60mm T'body,big valves,big VAM,LA3,1990 5.0L WC T5 0.82 5th gear, Cossy sway bar, Powerflex, Dynalites, Focus SVT rotors,Koni yellow sleeve over 8"x300lb/in springs,Scorch bumper cover, 17x7.5x40mm Binno wheels, 225/45-17 Kumho 712 tires

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Re: is there a head direct fit that cn replace turbo head

Post by DPDISXR4Ti » Tue Jan 05, 2016 6:25 pm

James Wieler wrote:I don't think it cracked because it was from an NA car as the casting and general construction of NA and turbo heads appear to be very similar. It likely cracked because that is what these heads do and turbos are likely more prone to cracking simply because of the increased exhaust heat.
Yes.
Brad

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Re: is there a head direct fit that cn replace turbo head

Post by intimidatorj » Tue Jan 05, 2016 6:50 pm

Well crap now I'm gonna have to buy new valve and valve seats then correct

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Re: is there a head direct fit that cn replace turbo head

Post by DPDISXR4Ti » Tue Jan 05, 2016 10:57 pm

intimidatorj wrote:Well crap now I'm gonna have to buy new valve and valve seats then correct
Depends. It may very well have been rebuilt with "turbo" valves. Regardless, many N/A heads have been used in turbo applications and survived.
Brad

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Re: is there a head direct fit that cn replace turbo head

Post by James Wieler » Wed Jan 06, 2016 10:43 am

From what I understand the turbo head seats are induction hardened. In other words there are not separate replaceable seats installed. At least none of the heads I've worked on have replaceable seats. I'm sure some can be installed however. I think new seats run in the $20 each range and turbo valves are around the same price.
T3/T40E-50 trim, 3" exh, FMIC, gutted/rotated upper, ported lower intake,60mm T'body,big valves,big VAM,LA3,1990 5.0L WC T5 0.82 5th gear, Cossy sway bar, Powerflex, Dynalites, Focus SVT rotors,Koni yellow sleeve over 8"x300lb/in springs,Scorch bumper cover, 17x7.5x40mm Binno wheels, 225/45-17 Kumho 712 tires

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Re: is there a head direct fit that cn replace turbo head

Post by John V » Wed Jan 06, 2016 11:12 am

James Wieler wrote:From what I understand the turbo head seats are induction hardened. In other words there are not separate replaceable seats installed. At least none of the heads I've worked on have replaceable seats. I'm sure some can be installed however. I think new seats run in the $20 each range and turbo valves are around the same price.
Everything after unleaded and MOST things before unleaded had induction hardened seats on cast iron heads..
And valve quality went way up after unleaded was the only thing...they had to or valve seat recession would have been unacceptable and cars would not have been able to meet the old "emissions must be met for min 50,000 miles" EPA requirement.

On the V6 Cologne like in Scorpios the valves went from a relatively soft 2 piece valve to a 1 piece forging, chrome plated stems and a stellite face---an excellent valve...They worked fine for in no-lead use for a bazillion miles..Not theoretical, I've used and installed literally hundreds of them..
As for the n.a. vs turbo head casting the later n.a. heads COULD be used as is..Its really a nicer chamber but of course compression ratio would have to be corrected. Engines with big 96mm bores and a sparkie plug over on one side* ---and cast iron---will not be happy with much compression and boost compared to engines with smaller bore---say around "the magic 86mm", aluminum heads and a really nice pent roof 4v head. That's just the way it is.
Grind chambers or buy dished pistons but get the comp back to about 8:1 or count on either lowered boost, or badly compromised ignition advance..



* that's certainly why Ford did 2 sparkie plugskies: short distance for flame front propagation for quicker burn in the few milliseconds you have to do a complete burn
Last edited by John V on Mon Jan 18, 2016 9:35 pm, edited 1 time in total.
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