Help - Search - Members - Calendar
Full Version: 2.0 head help. non 2.0 heads
914World.com > The 914 Forums > 914World Garage
broomhandle
Hello,

I have had a roller since 2009. It needs to get moving ASAP or I will need to sell the car. I have a 2.0 block and pistons. but I have non 2.0 heads. I currently have a set of 1.8 heads with cracked valves, and a set of perfect 2.0 bus heads.

Would either of these heads work if I had them cut for the 96 pistons? Right now I just want to get the car moving again. I was thinking of using the 1.8 heads, and selling the bus 2.0's.

any thoughts?

And does anybody know of a shop that can do this in the Sacramento/San Fransisco area?

914sgofast2
The bus heads will fit without modifications. For a shop in Sacramento, try IPB Autosport. For a machine shop, try Del’s Machine Shop.
porschetub
QUOTE(914sgofast2 @ Nov 5 2020, 07:36 AM) *

The bus heads will fit without modifications. For a shop in Sacramento, try IPB Autosport. For a machine shop, try Del’s Machine Shop.


Yes they will but if they aren't euro spec they will have rather small inlet and exhaust valves,end of the day any bus head will have smaller valves than the 914 type and will limit performance as they designed for low end torque.
I don't remember pulling down a bus T4 and not finding cracks ,bad seats and worn out guides....they get a very hard life and are also even more prone the breaking exhaust valves.
Many years ago I purchased a set of rebuilt 2.0 euro carb heads in amazing condition and fitted them to my last recent build,pretty rare to find a used set in this condition IMO.
Click to view attachment
Good luck.
broomhandle
So would the better option to use the 1.8 heads bored out? sounds like the 2.0 bus heads will make it a bus motor.
porschetub
QUOTE(broomhandle @ Nov 5 2020, 10:04 AM) *

So would the better option to use the 1.8 heads bored out? sounds like the 2.0 bus heads will make it a bus motor.

Yes very true sad.gif the engine will most likely suffer a reduced top end and "run out of breath" @ the upper RPM range, the bus heads are usually very low compression so more power loss .
Depends what you have to spend,I would try and find a good set of core 2.0 heads and replace exhaust valves (minimum ),and any worn valve guides and then get them flycut for a positive barrel to head seal.
Good luck again beerchug.gif .
broomhandle
QUOTE(porschetub @ Nov 4 2020, 02:52 PM) *

QUOTE(broomhandle @ Nov 5 2020, 10:04 AM) *

So would the better option to use the 1.8 heads bored out? sounds like the 2.0 bus heads will make it a bus motor.

Yes very true sad.gif the engine will most likely suffer a reduced top end and "run out of breath" @ the upper RPM range, the bus heads are usually very low compression so more power loss .
Depends what you have to spend,I would try and find a good set of core 2.0 heads and replace exhaust valves (minimum ),and any worn valve guides and then get them flycut for a positive barrel to head seal.
Good luck again beerchug.gif .


My plan was to go subaru. I used to own a 1.8, subaru to me is the way to go. I have had this 2.0 block for so long trying to find heads. Right now I need to get the car moving, or I will need to sell it. I think I have a trashed complete 1.7 as well.. maybe I will go that route.

TargaToy
QUOTE(broomhandle @ Nov 4 2020, 05:04 PM) *

So would the better option to use the 1.8 heads bored out? sounds like the 2.0 bus heads will make it a bus motor.


If you're talking about boring out the registers of the heads to fit 2.0 cylinders, you shouldn't have to. They should bolt on and would have larger valves than the bus 2.0 heads (as was mentioned by someone else).
broomhandle
QUOTE(TargaToy @ Nov 4 2020, 04:50 PM) *

QUOTE(broomhandle @ Nov 4 2020, 05:04 PM) *

So would the better option to use the 1.8 heads bored out? sounds like the 2.0 bus heads will make it a bus motor.


If you're talking about boring out the registers of the heads to fit 2.0 cylinders, you shouldn't have to. They should bolt on and would have larger valves than the bus 2.0 heads (as was mentioned by someone else).


You are saying the 1.8 heads would mount and work on the 2.0 block?
yellowporky
Yes the 1,8 heads will bolt on but i have been told they are prone to dropping seats. Not sure how common this is but when i was researching building my 1.7 into a 1911 i saw this multiple times.
914sgofast2
All Type 4 heads will bolt to the short block, but 1.7 heads need to be flycut to fit over the 2.0 cylinder barrels. The 2.0 bus heads have the same size valves as the Porsche 1.7 heads, so using them would reduce the ultimate air flow at higher rpms. You should be aware that 2.0 bus heads have two different exhaust port types. The earlier 2.0 bus heads use the oval copper exhaust gaskets like all Porsche 914’s use. The later 2.0 bus heads use rectangular port composite metal exhaust gaskets that will not work with the Porsche 914 exhaust systems used on 1.7s , 1.8s, and 2.0s. You did not state what type of exhaust ports your 2.0 bus heads have.

The 1.8 heads will fit over the 2.0 cylinder barrels without any modifications. They have the exhaust ports that are compatible with the 914 exhaust system.

The ultimate question is whether you simply want a quick and dirty fix to get a running engine for your car or a longer term fix. If you have 2.0 bus heads with the oval exhaust ports, they will bolt right up and you can use them to make a running engine that will allow you to move your 914 around. If you want a longer term running engine, then get the 1.8 liter heads fixed and use them to build a higher performance engine. If I remember correctly, the rebuilt Porsche heads sold by vendors such as Auto Atlanta are based on the 1.8 liter heads since they have bigger valves than the 1.7 liter heads but are not as prone to dropping valve seats as the 2.0 Porsche 914 heads.
barefoot

Yes very true sad.gif the engine will most likely suffer a reduced top end and "run out of breath" @ the upper RPM range, the bus heads are usually very low compression so more power loss .
Depends what you have to spend,I would try and find a good set of core 2.0 heads and replace exhaust valves (minimum ),and any worn valve guides and then get them flycut for a positive barrel to head seal.
Good luck again beerchug.gif .
[/quote]

The 2.0 heads have 60cc chambers, where the bus heads have 48cc chambers, so will yield substantially more compression mated to a 2.0 motor.
broomhandle
QUOTE(914sgofast2 @ Nov 5 2020, 12:15 PM) *

All Type 4 heads will bolt to the short block, but 1.7 heads need to be flycut to fit over the 2.0 cylinder barrels. The 2.0 bus heads have the same size valves as the Porsche 1.7 heads, so using them would reduce the ultimate air flow at higher rpms. You should be aware that 2.0 bus heads have two different exhaust port types. The earlier 2.0 bus heads use the oval copper exhaust gaskets like all Porsche 914’s use. The later 2.0 bus heads use rectangular port composite metal exhaust gaskets that will not work with the Porsche 914 exhaust systems used on 1.7s , 1.8s, and 2.0s. You did not state what type of exhaust ports your 2.0 bus heads have.

The 1.8 heads will fit over the 2.0 cylinder barrels without any modifications. They have the exhaust ports that are compatible with the 914 exhaust system.

The ultimate question is whether you simply want a quick and dirty fix to get a running engine for your car or a longer term fix. If you have 2.0 bus heads with the oval exhaust ports, they will bolt right up and you can use them to make a running engine that will allow you to move your 914 around. If you want a longer term running engine, then get the 1.8 liter heads fixed and use them to build a higher performance engine. If I remember correctly, the rebuilt Porsche heads sold by vendors such as Auto Atlanta are based on the 1.8 liter heads since they have bigger valves than the 1.7 liter heads but are not as prone to dropping valve seats as the 2.0 Porsche 914 heads.


So does anybody know what a good perf mod to the 1.8 head would be?

what size valves? would that be the only mod? the 2.0 914 heads are next to impossible, and I feel I am done looking for them, I don't care anymore. I am good with modding a 1.8 head. running that for awhile, enjoy it.

and I will sell off the 2.0 bus heads. I bought the engine with the "heads", and when I saw them I was bummed..

all good. I am cool with 1.8 heads.
Bleyseng
For 1.8 heads the minimum size for performance would be 42x38 valves. I actually am using that in my bus.
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.