Can anyone identify these Cylinder heads?
- Thread starter Sportmachines
- Start date
Sportmachines
Active member
Re: Can anyone identify these Cylinder heads?
Here is the answer. So this makes even less sence.
Here is the answer. So this makes even less sence.
turbodig
Active member
Re: Can anyone identify these Cylinder heads?
You guys were talking about some modded heart-shaped L35s several years ago. (Like more than 4)
Either that, or I've been clairvoyant for the last 5 years and didn't know it.
Were the guideplates on there? GM issue?
I'd be really curious to see how those guideplates line up with the pushrods in there...
You guys were talking about some modded heart-shaped L35s several years ago. (Like more than 4)
Either that, or I've been clairvoyant for the last 5 years and didn't know it.
Were the guideplates on there? GM issue?
I'd be really curious to see how those guideplates line up with the pushrods in there...
midnightbluS10
Banned
My money is on marine heads.
SY2932
Administrator
Re: Can anyone identify these Cylinder heads?
Interesting head, definitely reworked based on the seal in the first pic. It is bonded with a temperature sensitive epoxy that will melt and make the seal come off if the head is overheated. Used for warranty compliance in the event of a problem. So the $64,000 is where did they come from. I'm guessing from the "cloak and dagger" theme of this thread that it's on a need to know basis
...
Interesting head, definitely reworked based on the seal in the first pic. It is bonded with a temperature sensitive epoxy that will melt and make the seal come off if the head is overheated. Used for warranty compliance in the event of a problem. So the $64,000 is where did they come from. I'm guessing from the "cloak and dagger" theme of this thread that it's on a need to know basis
...
leadfoot
Member
Re: Can anyone identify these Cylinder heads?
Does he have a flow bench? Get them tested if he does. :tup:
Does he have a flow bench? Get them tested if he does. :tup:
turbodig
Active member
Re: Can anyone identify these Cylinder heads?
I kinda thought these looked reworked. There is some discoloration in the area where an L35 chamber would normally be.
That doesn't explain Jack's take-offs from his Astro Van that were on there since new.
Interesting head, definitely reworked based on the seal in the first pic. It is bonded with a temperature sensitive epoxy that will melt and make the seal come off if the head is overheated. Used for warranty compliance in the event of a problem. So the $64,000 is where did they come from. I'm guessing from the "cloak and dagger" theme of this thread that it's on a need to know basis
I kinda thought these looked reworked. There is some discoloration in the area where an L35 chamber would normally be.
That doesn't explain Jack's take-offs from his Astro Van that were on there since new.
DaveP
Active member
Re: Can anyone identify these Cylinder heads?
8181's. F034, June 3, 1994. The intake 'cut out' looks a little odd. Push rod guide plates definitely not OEM. Valve springs. And of course the chamber shape. All very odd that these variations exist on the same casting # that we are so accustomed to seeing with the earlier chamber shape.
One thought I had was that the date could be June 3, 2005. But this doesn't make sense either. The 4.3 had been out of production for 3 years by then. I give up. I have not a clue what they are, nor more importantly, how to find more of them.
8181's. F034, June 3, 1994. The intake 'cut out' looks a little odd. Push rod guide plates definitely not OEM. Valve springs. And of course the chamber shape. All very odd that these variations exist on the same casting # that we are so accustomed to seeing with the earlier chamber shape.
One thought I had was that the date could be June 3, 2005. But this doesn't make sense either. The 4.3 had been out of production for 3 years by then. I give up. I have not a clue what they are, nor more importantly, how to find more of them.
turbodig
Active member
Re: Can anyone identify these Cylinder heads?
The industrial and marine engines would continue past that date code. But, even if they did, they would likely be a full vortec design.
The chamber shape is typically part of the raw casting vs. being machined out. I find it tough to believe GM would create a new mold with the same casting number, unless this was a modification to the original 181 casting. The "hump" in the mold that creates chamber shape could theoretically be tweaked to leave a bit extra material in there.
I had a heck of a time getting guideplates on my L35s that would align the rockers correctly. I messed around with adjustable ones, and I still really didn't get an alignment that I really liked. If the plates on these are standard SBC parts, I'll bet they have issues.
The industrial and marine engines would continue past that date code. But, even if they did, they would likely be a full vortec design.
The chamber shape is typically part of the raw casting vs. being machined out. I find it tough to believe GM would create a new mold with the same casting number, unless this was a modification to the original 181 casting. The "hump" in the mold that creates chamber shape could theoretically be tweaked to leave a bit extra material in there.
I had a heck of a time getting guideplates on my L35s that would align the rockers correctly. I messed around with adjustable ones, and I still really didn't get an alignment that I really liked. If the plates on these are standard SBC parts, I'll bet they have issues.
DaveP
Active member
Re: Can anyone identify these Cylinder heads?
I thought of that too. It should be full Vortec. And I believe the 4.3 and 5.7 were shut down at the same time when Flint casting and engine assembly discontinued the production of those engines. The 5.7 was replaced by the LS series, because it was obsolete. The 4.3 was machined on the same lines, so it went away too. The 2-piece rear seal SBC is still cast and produced in Mexico. Not sure about 4.3. But I think the 4.3 ceased production in all forms in 2002.
I vaguely remember reading about guide plates for the 4.3. And that there are two different P/N's depending on which cyl the plate is on. I'd have to search for awhile to find it. But, yes the 4.3 guide plates are challenging.
I thought of that too. It should be full Vortec. And I believe the 4.3 and 5.7 were shut down at the same time when Flint casting and engine assembly discontinued the production of those engines. The 5.7 was replaced by the LS series, because it was obsolete. The 4.3 was machined on the same lines, so it went away too. The 2-piece rear seal SBC is still cast and produced in Mexico. Not sure about 4.3. But I think the 4.3 ceased production in all forms in 2002.
I vaguely remember reading about guide plates for the 4.3. And that there are two different P/N's depending on which cyl the plate is on. I'd have to search for awhile to find it. But, yes the 4.3 guide plates are challenging.
Sportmachines
Active member
Re: Can anyone identify these Cylinder heads?
This is the important part of DaveP's quote "how to find more of them"
This is the important part of DaveP's quote "how to find more of them"
Sportmachines
Active member
Re: Can anyone identify these Cylinder heads?
Here are the unported flow numbers.
Flowed on Superflow 1020
Flowed at 28 in WC
4.030 bore
821 pipe
Cyl head A
Lift Intake Exhaust
50 30 25
100 59 58
150 86 93
200 110 118
205 130 139
300 148 154
350 165 166
400 179 175
450 190 180
500 198 183
550 204 185
600 205 185
650 206 185
Cyl head B
Lift Intake Exhaust
50 30 24
100 60 55
150 89 87
200 113 113
205 134 135
300 153 150
350 171 163
400 184 170
450 195 172
500 201 172
550 202 173
600 203 174
650 205 175
So we decided to use these heads. They bolt right up and have the Vortech chamber. We had them ported and flow tested. Ported numbers to follow. Still a bunch of info to gather on these heads. But right now it is looking pretty good for Sy/Ty community.
Here are the unported flow numbers.
Flowed on Superflow 1020
Flowed at 28 in WC
4.030 bore
821 pipe
Cyl head A
Lift Intake Exhaust
50 30 25
100 59 58
150 86 93
200 110 118
205 130 139
300 148 154
350 165 166
400 179 175
450 190 180
500 198 183
550 204 185
600 205 185
650 206 185
Cyl head B
Lift Intake Exhaust
50 30 24
100 60 55
150 89 87
200 113 113
205 134 135
300 153 150
350 171 163
400 184 170
450 195 172
500 201 172
550 202 173
600 203 174
650 205 175
So we decided to use these heads. They bolt right up and have the Vortech chamber. We had them ported and flow tested. Ported numbers to follow. Still a bunch of info to gather on these heads. But right now it is looking pretty good for Sy/Ty community.
WyoSyclone
Active member
Re: Can anyone identify these Cylinder heads?
I found this in one of John's old posts and thought it may be worth re-listing in this thread. Sometimes these numbers are hard to find all in one place (I've reformatted it a bit to make it a bit easier to follow).... HTH
If we can re-evaluate this info and make any updates to it that are needed, it would help all in the future (this original post was from 2002)
From John...
"Note the following about 4.3 heads...
I have determined that:
- '92 & '93 CPI head (L35 type) have four possible casting nos. available #10238181, 10077626, 14099064, & 10240209 that all have an 8 degree top angle cut in the ports and screw-in rocker studs, with the top of the ports having a small circular cutout for the injector holes in the intake manifold.
- '88-'92 TBI engines (LB4 type) have head casting #10144103 which is the older style TBI head that has an intake port that is rectangular in shape with no circular cutout on the top of the port & a highly restricted intake throat compared to the CPI style head .
- '93 TBI engine (also LB4 code) has the same four possible casting nos. available as the '92-'93 CPI engines that all have an 8 degree top angle cut in the ports with the top of the ports having a small circular cutout just like the CPI heads, but they have press-in rocker studs rather than screw-in rocker studs. The use of these CPI style heads on the '93 up TBI engines is why the HP rating of this engine was raised from 160 HP to 165 HP.
- '92 TBI head is not the same as the '92 CPI head as detailed above, and there may be a few early '93 model TBI engines that were carry overs from the '92 model year that still have the old style '92 back TBI heads as well.
- '94-'95 CPI head (still an L35 code) has only two possible casting nos. available #10238181 & 10240209 that has a 30 degree top angle cut in the ports and screw-in rocker studs, with the top of the ports having a small circular cutout.
- '94-'95 TBI head (still an LB4 code) also has the same two possible casting nos. available that has a 30 degree top angle cut in the ports with the top of the ports having a small circular cutout on the top, but once again come with press-in rocker studs.
- '94-'95 TBI head is the same as the '94-'95 CPI head, except for the press-in versus screw-in stud issue (although sometimes the TBI engines come with screw-in rocker studs as well).
- '94-'95 heads (both TBI & CPI) are different from the '92-'93 CPI & '93 TBI heads only in that the top angle cut in the ports is 30 degrees versus 8 degrees (and of course there is still the press-in versus screw-in rocker stud differences of the TBI & CPI heads).
- '96-up heads (still L35 as well) on the CMFSI engines have head casting no. 10235772 which is different from '92-'95 heads due to the different intake bolt mounting pattern to accomodate the newer style intake manifold. These heads come on both the '96 up VIN X & VIN W engines." end quote
Keywords: L35 head part numbers, L35 heads, L35 part numbers, L35 casting numbers, L35 casting #'s, L35's, L35s
I found this in one of John's old posts and thought it may be worth re-listing in this thread. Sometimes these numbers are hard to find all in one place (I've reformatted it a bit to make it a bit easier to follow).... HTH
If we can re-evaluate this info and make any updates to it that are needed, it would help all in the future (this original post was from 2002)
From John...
"Note the following about 4.3 heads...
I have determined that:
- '92 & '93 CPI head (L35 type) have four possible casting nos. available #10238181, 10077626, 14099064, & 10240209 that all have an 8 degree top angle cut in the ports and screw-in rocker studs, with the top of the ports having a small circular cutout for the injector holes in the intake manifold.
- '88-'92 TBI engines (LB4 type) have head casting #10144103 which is the older style TBI head that has an intake port that is rectangular in shape with no circular cutout on the top of the port & a highly restricted intake throat compared to the CPI style head .
- '93 TBI engine (also LB4 code) has the same four possible casting nos. available as the '92-'93 CPI engines that all have an 8 degree top angle cut in the ports with the top of the ports having a small circular cutout just like the CPI heads, but they have press-in rocker studs rather than screw-in rocker studs. The use of these CPI style heads on the '93 up TBI engines is why the HP rating of this engine was raised from 160 HP to 165 HP.
- '92 TBI head is not the same as the '92 CPI head as detailed above, and there may be a few early '93 model TBI engines that were carry overs from the '92 model year that still have the old style '92 back TBI heads as well.
- '94-'95 CPI head (still an L35 code) has only two possible casting nos. available #10238181 & 10240209 that has a 30 degree top angle cut in the ports and screw-in rocker studs, with the top of the ports having a small circular cutout.
- '94-'95 TBI head (still an LB4 code) also has the same two possible casting nos. available that has a 30 degree top angle cut in the ports with the top of the ports having a small circular cutout on the top, but once again come with press-in rocker studs.
- '94-'95 TBI head is the same as the '94-'95 CPI head, except for the press-in versus screw-in stud issue (although sometimes the TBI engines come with screw-in rocker studs as well).
- '94-'95 heads (both TBI & CPI) are different from the '92-'93 CPI & '93 TBI heads only in that the top angle cut in the ports is 30 degrees versus 8 degrees (and of course there is still the press-in versus screw-in rocker stud differences of the TBI & CPI heads).
- '96-up heads (still L35 as well) on the CMFSI engines have head casting no. 10235772 which is different from '92-'95 heads due to the different intake bolt mounting pattern to accomodate the newer style intake manifold. These heads come on both the '96 up VIN X & VIN W engines." end quote
Keywords: L35 head part numbers, L35 heads, L35 part numbers, L35 casting numbers, L35 casting #'s, L35's, L35s
dgoodhue
BuSTeD 4.3
Re: Can anyone identify these Cylinder heads?
Those are some good numbers for a 'L35 head'.
Those are some good numbers for a 'L35 head'.
WyoSyclone
Active member
Re: Can anyone identify these Cylinder heads?
And, found this info on 4.3 cylinder heads from Doug Anderson's site...
This, and some other interesting info here...
http://www.hotsixes.com/index.php?option=com_content&view=article&id=14&Itemid=12
below information, with the pics added... http://www.enginebuildermag.com/Article/2427/rebuilding_the_new_chevy_262.aspx
"CYLINDER HEADS
There have been several cylinder heads used on the 262 since it began in ’85. Some of the changes appear to be minor, but most of them will create problems if the wrong head is used in the wrong place. Here’s an overview year by year:
1985-’86: The 1985 and ’86 engines used a 14079248 casting. It had two holes on one end and three on the other end.
1987-’91 TRUCK, EXCEPT HEAVY DUTY AND ’87-’93 CARS: These heads were the same as the earlier ones except that they had three bolt holes on both ends. The intake surface above the ports was quite narrow; it’s only about 0.250″ wide. The unmachined, cast ledge on the top edge of the head was 0.600″ wide. Look for c/n 14094768, 10144103, 14099067 or 12553050. All of these heads had adjustable rockers.
1992 TRUCK WITH TBI AND NO BALANCE SHAFT: These heads had a wider surface for the intake gasket even though they didn’t need it because all of the tooling was changed to accommodate the new heads for the VIN “W” CFI engines that were introduced in ’92. The 10144103 casting was carried over from ’91, but it had the wide intake with straight ports on the top. It can be used along with any of the earlier 14094768, 10144103, 14099067 or 12553050 castings from ’87 through ’91.
1992-’93 TRUCK WITH CFI, BALANCE SHAFT: When the high output VIN “W” engine with central fuel injection was introduced in ’92, the heads were redesigned for the application. They had “eyebrows” added to the top of the intake ports to make room for the injector nozzles, so the intake surface above the ports was increased by 0.250˝ for improved sealing, and the cast ledge above it was narrowed down to 0.350˝ to provide more room for the intake manifold.
The 10077626, 14099064, 10240209 or 10238181 castings were used, but be sure to check them over carefully because there are two versions of the 10238181 and 10240209 castings with an important difference. In ’92 and ’93, they came with an 8° top angle on the intake seat and a 75° throat, but that was changed to a 30° top angle with an 80° throat in ’94. Separate the 8° heads from the 30° heads and use them only on the ’92 and ’93 engines.
Tonawanda switched to “net lash” rockers in ’92, so some of these are adjustable and some aren’t.
1993 TRUCK WITH TBI, EXCEPT HEAVY DUTY: The intake manifold on the TBI motor was modified in ’93 to take advantage of the wider intake surface that was machined on the ’92 and up heads, so these engines must have the heads with the wide intake and should use the castings with the 8° top angle on the intake seat.
1994-’95 TRUCK WITH TBI OR CFI, EXCEPT HEAVY DUTY: The top angle for the intake seat was changed from 8° to 30° and the throat was opened up from 75° to 80° to give a 10% increase in intake airflow for better performance in ’94. The same heads were used on both the TBI and CFI engines through ’95.
Both the 10238181 and 10240209 castings were used, but they have to be visually sorted because the early ones with the 8° seat probably shouldn’t be used on the ’94s and ’95s. If you do decide to stretch the rules and use the ’93 heads on a ’94-’95 engine, be sure to use them in pairs. Some of the ’94s still had adjustable rockers because Romulus didn’t switch over to “net lash” until ’95.
1996-’98 ALL TRUCKS EXCEPT HEAVY DUTY: There was another all new head introduced in ’96. It had bigger intake and exhaust ports, no exhaust crossover and four angled bolts for the intake. It’s the 10235772 casting that was used up through ’98.
1989-’95 HEAVY DUTY TRUCK WITH TBI: There have been three different heads used on the heavy duty 262 since ’89.
1) 1989-’92: The original head, c/n 14099066 was used up through ’91. The 10144115 casting with the wider intake surface showed up in ’92 even though the narrow one still worked. Both of these castings are interchangeable.
2) 1993: The 14099070 casting came with an 8° top angle on the intake seat in ’93, but it was also available with the 30° top angle in ’94 and ’95. Sort them accordingly and use them in pairs.
3) 1994-’95: The 14099070 casting with the 30° top angle for better airflow should be used on the ’94 and ’95 engines. Be sure to use them in pairs. See photo.
All of these heavy duty heads had hard donut seats, replaceable guides and heavy duty exhaust valves with 3/8″ stems.
1991-’93 SYCLONE AND TYPHOON WITH TURBOCHARGER: The turbo motors used the same heads that were installed on the VIN “Z” throttle body motors. It appears that they came with the narrow intake surface all the way through ’93. Look for the 14094768, 10144103 and 1409967 castings."
And, found this info on 4.3 cylinder heads from Doug Anderson's site...
This, and some other interesting info here...
http://www.hotsixes.com/index.php?option=com_content&view=article&id=14&Itemid=12
below information, with the pics added... http://www.enginebuildermag.com/Article/2427/rebuilding_the_new_chevy_262.aspx
"CYLINDER HEADS
There have been several cylinder heads used on the 262 since it began in ’85. Some of the changes appear to be minor, but most of them will create problems if the wrong head is used in the wrong place. Here’s an overview year by year:
1985-’86: The 1985 and ’86 engines used a 14079248 casting. It had two holes on one end and three on the other end.
1987-’91 TRUCK, EXCEPT HEAVY DUTY AND ’87-’93 CARS: These heads were the same as the earlier ones except that they had three bolt holes on both ends. The intake surface above the ports was quite narrow; it’s only about 0.250″ wide. The unmachined, cast ledge on the top edge of the head was 0.600″ wide. Look for c/n 14094768, 10144103, 14099067 or 12553050. All of these heads had adjustable rockers.
1992 TRUCK WITH TBI AND NO BALANCE SHAFT: These heads had a wider surface for the intake gasket even though they didn’t need it because all of the tooling was changed to accommodate the new heads for the VIN “W” CFI engines that were introduced in ’92. The 10144103 casting was carried over from ’91, but it had the wide intake with straight ports on the top. It can be used along with any of the earlier 14094768, 10144103, 14099067 or 12553050 castings from ’87 through ’91.
1992-’93 TRUCK WITH CFI, BALANCE SHAFT: When the high output VIN “W” engine with central fuel injection was introduced in ’92, the heads were redesigned for the application. They had “eyebrows” added to the top of the intake ports to make room for the injector nozzles, so the intake surface above the ports was increased by 0.250˝ for improved sealing, and the cast ledge above it was narrowed down to 0.350˝ to provide more room for the intake manifold.
The 10077626, 14099064, 10240209 or 10238181 castings were used, but be sure to check them over carefully because there are two versions of the 10238181 and 10240209 castings with an important difference. In ’92 and ’93, they came with an 8° top angle on the intake seat and a 75° throat, but that was changed to a 30° top angle with an 80° throat in ’94. Separate the 8° heads from the 30° heads and use them only on the ’92 and ’93 engines.
Tonawanda switched to “net lash” rockers in ’92, so some of these are adjustable and some aren’t.
1993 TRUCK WITH TBI, EXCEPT HEAVY DUTY: The intake manifold on the TBI motor was modified in ’93 to take advantage of the wider intake surface that was machined on the ’92 and up heads, so these engines must have the heads with the wide intake and should use the castings with the 8° top angle on the intake seat.
1994-’95 TRUCK WITH TBI OR CFI, EXCEPT HEAVY DUTY: The top angle for the intake seat was changed from 8° to 30° and the throat was opened up from 75° to 80° to give a 10% increase in intake airflow for better performance in ’94. The same heads were used on both the TBI and CFI engines through ’95.
Both the 10238181 and 10240209 castings were used, but they have to be visually sorted because the early ones with the 8° seat probably shouldn’t be used on the ’94s and ’95s. If you do decide to stretch the rules and use the ’93 heads on a ’94-’95 engine, be sure to use them in pairs. Some of the ’94s still had adjustable rockers because Romulus didn’t switch over to “net lash” until ’95.
1996-’98 ALL TRUCKS EXCEPT HEAVY DUTY: There was another all new head introduced in ’96. It had bigger intake and exhaust ports, no exhaust crossover and four angled bolts for the intake. It’s the 10235772 casting that was used up through ’98.
1989-’95 HEAVY DUTY TRUCK WITH TBI: There have been three different heads used on the heavy duty 262 since ’89.
1) 1989-’92: The original head, c/n 14099066 was used up through ’91. The 10144115 casting with the wider intake surface showed up in ’92 even though the narrow one still worked. Both of these castings are interchangeable.
2) 1993: The 14099070 casting came with an 8° top angle on the intake seat in ’93, but it was also available with the 30° top angle in ’94 and ’95. Sort them accordingly and use them in pairs.
3) 1994-’95: The 14099070 casting with the 30° top angle for better airflow should be used on the ’94 and ’95 engines. Be sure to use them in pairs. See photo.
All of these heavy duty heads had hard donut seats, replaceable guides and heavy duty exhaust valves with 3/8″ stems.
1991-’93 SYCLONE AND TYPHOON WITH TURBOCHARGER: The turbo motors used the same heads that were installed on the VIN “Z” throttle body motors. It appears that they came with the narrow intake surface all the way through ’93. Look for the 14094768, 10144103 and 1409967 castings."
Last edited:
WyoSyclone
Active member
Re: Can anyone identify these Cylinder heads?
So to get back to answering the question, they could be the elusive 1994 10238181 that changed to a 30° top angle with an 80° throat in ’94. I've been able to find pics of the '92-'93 models with the D-shaped combustion chamber, but haven't found a pic of a '94 181's combustion chamber... maybe they switched to the kidney style in '94 before they went to the 4-bolt intakes??
...or like Dig suggested - maybe someone welded the chambers on a set of 181's.
I guess measuring the top angle and throat angle would get us closer to telling us what they are.
So to get back to answering the question, they could be the elusive 1994 10238181 that changed to a 30° top angle with an 80° throat in ’94. I've been able to find pics of the '92-'93 models with the D-shaped combustion chamber, but haven't found a pic of a '94 181's combustion chamber... maybe they switched to the kidney style in '94 before they went to the 4-bolt intakes??
...or like Dig suggested - maybe someone welded the chambers on a set of 181's.
I guess measuring the top angle and throat angle would get us closer to telling us what they are.
Sportmachines
Active member
Re: Can anyone identify these Cylinder heads?
Sorry to keep you waiting guys, but we have been super busy, and forgot to get back onto this thread.
Dig hit the nail on the head. (although we did tell him years ago about this idea and can't believe he remembered). They are a set of heads that we had made. They are an 181 L35 casting, which we then had material welded into the chamber, then milled to match a Vortec chamber. And then also had 2.02 and 1.60 valves with a 3 angle valve job, ported and polished.
Our goal was to have a set of heads that performed like the vortecs, but bolted up the the stock manifold. We could not recreat the "swirl" intake runner pattern, but were able to duplicate the chamber. We think they could prove to be a viable option for our trucks.
We also reflowed them after the porting..... we will post those number as well. Stay tuned!
Sorry to keep you waiting guys, but we have been super busy, and forgot to get back onto this thread.
Dig hit the nail on the head. (although we did tell him years ago about this idea and can't believe he remembered). They are a set of heads that we had made. They are an 181 L35 casting, which we then had material welded into the chamber, then milled to match a Vortec chamber. And then also had 2.02 and 1.60 valves with a 3 angle valve job, ported and polished.
Our goal was to have a set of heads that performed like the vortecs, but bolted up the the stock manifold. We could not recreat the "swirl" intake runner pattern, but were able to duplicate the chamber. We think they could prove to be a viable option for our trucks.
We also reflowed them after the porting..... we will post those number as well. Stay tuned!