You are here

173 head on 202

Hi, just reading in the 'peadia about putting 173 heads on a 202. How much of a difference would this make to the engines performance? Would I be better with a ported 202 head or could you just port the 173 head anyway? What sort of carb setup would be ideal?
thanks,
Jasper

Model: 
Engine: 

Comments

A 173 Head on a 202 is a good way of improving both horsepower and torque without having to change any other aspect of the engine.

By itself it is only one change. If you want big improvements, make big changes.

T

Shed
Holdenpaedia, they're the brakes Mate.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

T

My Shed

Holdenpaedia, they're the brakes Mate.

I always thought the 173 and 202 heads were the same. With the 202 having dished pistons to correct the comp ratio.
Is this not the case?
Cheers.
email

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

email
Campbells Shed
Postcode 3147.

the 173/s 202/s i have seen have all had either one of 2 casting numbers if a fixed rocker head: 2811930 or ????262. i also thought as campbell did above...

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

where is the article about 173 heads on 202 ??
i want to read..
thanks

My Shed - HZ

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Link

http://holdenpaedia....

T

Shed
Holdenpaedia, they're the brakes Mate.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

T

My Shed

Holdenpaedia, they're the brakes Mate.

Dunno if it's relevant to the red motors but in blue motors, the 173 head has diffrent chambers. Posted a pic on the main page for ya of my blue 173's head. (going to use it on Pam's red 202).

Oh and Jasper, I've yet to put mine on and try it but the most popular choice of carb on this forum for a 202 seems to be the webber carb off an XE/XF falcoon (No jetting changes required AFAIK).

"[http://gallery.oldho...|Republic of Dusty's Shed]"
EMAIL

"WANTED TO BUY.."RUST FREE" HK SINGLE LIGHT SUBFRAME"

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Want a headache ?
Nurse explains.. https://hooktube.com...
Jet fuel hoax https://hooktube.com...

If you've got a blue 173 head there. Can you check to see if there is any difference in the chambers of that, and the 202(EFI black) head I dropped up to you when I grabbed the van.
If there is a noticeable difference. Post up a piccy of the two, side by side.
Cheers.
email

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

email
Campbells Shed
Postcode 3147.

I was gunna do that as there is a BIG diffrence between the two but i was unsure how relevant it would be given that the one you give me is a EFI black.
I'll go do it...gimme half an hour or so. (the pic i posted on the main page is blue 173)

"[http://gallery.oldho...|Republic of Dusty's Shed]"
EMAIL

"WANTED TO BUY.."RUST FREE" HK SINGLE LIGHT SUBFRAME"

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Want a headache ?
Nurse explains.. https://hooktube.com...
Jet fuel hoax https://hooktube.com...

"[http://oldholden.com...|Done]" it on the main page as my shed is uploading too slow

"[http://gallery.oldho...|Republic of Dusty's Shed]"
EMAIL

"WANTED TO BUY.."RUST FREE" HK SINGLE LIGHT SUBFRAME"

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Want a headache ?
Nurse explains.. https://hooktube.com...
Jet fuel hoax https://hooktube.com...

A closed Chamber head ie 149/161/173 does not flow as good as an open chamber 179/186/202 head. I have had both heads on a flow bench and know that its true. to increase flow to equal that of an open chamber head you need to remove some of the material around the valve. pics www.hiy-po.com click closed chamber head link. When doing the research I stopped removing material when the flow rate was equal to that of an open chamber, removing more material would likely increase flow further. Before increasing the compresion keep in mind todays unleaded fuels are of a poorer quality and a higher compression motor will like 98 premium better than the less octane fuels. Also you will not be able to run as much advance in a higher compression engine and detonation and asociated problums will occur earlier leading to head gasket failure and higher running temperatures. If you run the engine on LPG then the higher compression is an advantage.

  • Like1
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

hiy_po
[http://gallery.oldho...|VK turbo build]
My Email

So will working the 173 heads reduce the compression?

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

(postcode 3460)
[http://gallery.oldho...|My Shed]

Standard HC 202 Head = 9.4:1 Compression Ratio.
173 LC Head on 202 = 10.5(+):1 Compression Ratio.

If you choose to remove metal from the 173 head there is still room to increase the compression ratio over the standard 202 head.

T

Shed
Holdenpaedia, they're the brakes Mate.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

T

My Shed

Holdenpaedia, they're the brakes Mate.

so, if you ported it, and put on larger lalves but left the inside (bottom -don't know what it's called) it would have the same high compression?

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

(postcode 3460)
[http://gallery.oldho...|My Shed]

just wondering something
Is your 173 a red or 12 port head?
Im going to assume its 12 port.
to make the head work better you need to get the airflow past the combustion chamber walls. Putting bigger valves in will just bring the walls closer to the valve. Keep in mind a std 12 port valve is the same size as a red XU-1 valve.
If you want to keep the compresion high you check how many cc your chamber is after your valves are deshrouded and you get the head shaved at a machine shop down to the cc you require to get the compresion you want. Once thats done while at the machine shop tell them you want a multiangle performance valve seat job and your valves back cut.
Just doing these things will increase your cylinderfill dramaticly. Bolt on some tripple CD-150 carbs and a good set of extractors and youll get some fun out of it.
If you want to go further then you look at big valves big springs moly retainers locks and a port job. A pocket port under a good multiangle seat job is usualy enough but you can port the whole intake if you want to move a huge volume of air/fuel in. Hopfuly I have shed some light.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

hiy_po
[http://gallery.oldho...|VK turbo build]
My Email

Yes, you have shed some light, but it is a red 173 head. Is it not worth bothering with?

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

(postcode 3460)
[http://gallery.oldho...|My Shed]

Yella terra red motor heads are very comon on evilbay and will pick the horsepower up to around the 100rwhp mark even with a crappy holley. They start at about $100 so when it comes to bang for buck they are hard to go pass. Tripple 150 cd's would be my choice of carb or a 465 holley on a 4BL Cain or redline intake manifold. When your looking for your head I would recomend getting an open chamber one. Itll just make it all easier for you to tune etc If you really want to stick with closed chambers theres a good buy here http://cgi.ebay.com.... was $124 when I looked at it and has roller rockers as well.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

hiy_po
[http://gallery.oldho...|VK turbo build]
My Email

Hey fellas. I've got a black 202 engine noQl and a yellow head no2811929.Is this a 173 head? Will extractors for a 202 still sit nicely.And should I get a thermostat for a 173. Cheers

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

You head is a high comp' 173
173 and 202 use the same extractors
I use the 202 thermostat in mine (probably the same rating as a 173, dunno)
Engine prefix QL is red motor btw.

AttachmentSize
Image icon HX pics 070.JPG2.24 MB
  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Want a headache ?
Nurse explains.. https://hooktube.com...
Jet fuel hoax https://hooktube.com...

Depends on what you have got. They use closed chamber heads to boost compression. I believe open chamber heads mix the fuel/air better. If you are building a new motor, your engine builder can determine the compression and change things like piston shape, deck height. Depending on what fuel you are using will determine the compression ratio.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

I use 98 in mine and it's only a bees dick off of pinging.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Want a headache ?
Nurse explains.. https://hooktube.com...
Jet fuel hoax https://hooktube.com...

Sounds about right, my 202 is undergoing machining at the moment, it'll be +30 12cc dish tops bring to comp down with 161 head with XU1 valves. The head has previously been decked but our piston choice is bringing the comp back to 9.75-1.

  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.

Cheers Shane

Email me
HOLDEN DOCTOR

Add new comment

Filtered HTML

  • Allowed HTML tags: <a> <strike> <blink> <i> <u> <br> <b>
  • Filtered words will be replaced with the filtered version of the word.
  • Lines and paragraphs break automatically.
  • Web page addresses and e-mail addresses turn into links automatically.

Plain text

  • Allowed HTML tags: <a> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>
  • No HTML tags allowed.
  • Filtered words will be replaced with the filtered version of the word.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Comment attachments
Files must be less than 100 MB.
Allowed file types: jpg jpeg gif png txt pdf bmp mov mp4 mp3 avi.
CAPTCHA
This question is used to make sure you are a human visitor and to prevent spam submissions. Email rusty@oldholden.com if you have a problem.
  • Like0
  • no like0
  • Holdenpaedia idea0
  • Funny0
  • Wrong Category0
Please use, Holdenpaedia will get the first box on the left side. Post any suggestions.