Need head identified

artz1731

artz1731

True Classic
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The head off my '88 Yugo 1100 is: 128A000
4469750
Pretty sure everything on a stock 1500 should start with "138"
Experts will finish the story soon...
Regards
 
It's not a stock 1500. I pretty sure it's a 1300 head of some sort, weather it's a Yugo head is my question.
The PO had this on to increase compression during the cars Hillclimb days.
Had it off a few years ago but didn't know much about it at the time.
 
If I am not mistaken the 1300 and the Yugo 1100 are fairly similar valve and runner wise. Did you measure the valves? 128 does indicate 1300 and the intakes would have been 36 mm the exhausts would be 31mm for both. The intake runners on those heads were 25mm vs 28mm for the 1500. If you go to Steve's ultimate SOHC thread it will cover all this. I thought all the NA heads had the decompression cutout but could be wrong. If the PO just switched the head and did not change anything then it was likely one step forward and one step back.
Regards
 
Not listed in the Ultimate SOHC thread. The best way other then trying to Google the PN: would be looking at the combuston chambers and/or measure the valves.
 
Well i wish I would have taken pictures the last time I had it milled. Can't remember if it had the cutouts milled off or not.
Might be a good time to remove and upgrade.
 
It would also have a date stamp on it... yugo would be date stamped in the 80's... if Matt's right and it's 77/78 US spec 1300 X19 head then it's a bit of a backwards step on a 1500 as it's an early combustion chamber shape.

Yugo 1300 carb head and modified a bit like rocco79/138 has done is a good economy compromise for a Euro spec 1500 head.

SteveC
 
Yeah Steve I believe it's time to pull it and see what work has been done. I have a 1500 head that might be worth putting some money into.
Midwest also has some interesting options also. I might go for one of his reworked 1500 heads and use the 40/80 Faza Cam that I currently am using.
 
What carburetor are you running or going to run? Single DCNF? Its looking like our setups are going to be very similar. Im going with a euro head/cam combo from steve. Will be interesting to compare eachothers cars once were done (if you go the modified US head w 40/80 cam route).
 
I am going modified Yugo head, no decompression cutouts so no need to mill off. Speced out to Euro 1500 head. Steve says my cam is Pittitore #77 bought as Alquati 40/80. Euro intake manifold with 34 Weber. Tube header with custom Borla. Bottom end is the German pistons(flat with little fly cuts not the NA caved in versions) bored over .6mm and the flywheel is lightened. Will be good comparison...
 
Sounds like a nice build.
I will have the euro intake, converted to fit the DCNF. I have a Vick's header installed currently. I dont think ill be messing with the bottom end.
I really need to pull the Head and take a look at what has been done to it before I do anything. The PO did Win quite a few Hillclimb events with this car so it by no means under powered in the low end of the rpm range. It lacks the power from about 5,500 and up. So I'm thinking it all comes back to the smaller ports on the head and current Alquati intake.
Kinda parked the car for the winter, if we get a warm weekend I'll be able to get the Head off and see what is what.
 
Getting nearer and nearer fellas! I cant wait for the weather to break. Will be comitting one way or another to my build soon. The anticipation is killing me! Lol. If you need a hand or just want to shoot the chit while your swapping out heads, lemme know. Im at the inlaws pretty often.
 
Eastep said:
Getting nearer and nearer fellas! I cant wait for the weather to break. Will be comitting one way or another to my build soon. The anticipation is killing me! Lol. If you need a hand or just want to shoot the chit while your swapping out heads, lemme know. Im at the inlaws pretty often.
Click to expand...
Where are the in-laws located?
 
artz1731 said:
Sounds like a nice build.
I will have the euro intake, converted to fit the DCNF. I have a Vick's header installed currently. I dont think ill be messing with the bottom end.
I really need to pull the Head and take a look at what has been done to it before I do anything. The PO did Win quite a few Hillclimb events with this car so it by no means under powered in the low end of the rpm range. It lacks the power from about 5,500 and up. So I'm thinking it all comes back to the smaller ports on the head and current Alquati intake.
Kinda parked the car for the winter, if we get a warm weekend I'll be able to get the Head off and see what is what.
Click to expand...

Pulling hard and then running out of puff at around 5500 rpm is quite typical for an 80mm width chamber on an 86mm bore engine. The smaller combustion chamber volume (especially if the full circular recess has been partially machined back) will bump the static CR well up from the stock 8.5:1... but around the 5500rpm mark the head flow just wont keep up with the engines air demand due to the proximity of the combustion chamber walls to the inlet valves periphery... a fancy way of saying it's shrouded.

Of course the drawback of fitting a head with a wider combustion chamber will mean the static compression ratio will likely drop... so you'll loose some of that low end punch... unless you also decide to bump the static compression ratio up again, usually by installing a set of small flycut pistons. The later style chamber will definitely benefit the flow rate above 5500rpm though, as the engine will maintain it's volumetric efficiency until much higher in the rev range, and it's simply a fact of physics, the higher you can cycle (that's REV) a four cycle engine AND MAINTAIN the volumentric efficiency, then you WILL produce more power.

SteveC
 
After reading your Ultimate SOHC write up about 20 times in the past few weeks I figured as much. I know fitting some different Pistons would be a gain but I'm trying to stay within a budget. I plan to swap out the 1300 head with one of MWB milled and ported 1500 carb heads, a modified for DCNF Euro Intake and sticking with the FAZA 40/80 Cam I am currently using. Also have a Vick's Header and Muffler installed but due to too much drone I have a CC insert in place right before the muffler. I need to find a better Muffler solution.
Hopefully all of that combined will give me what I'm looking for as a nice street car, I don't do any racing.
 
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