How to tell what year the engine is?

**Justin23454** · 10-22-2010, 07:12 AM

how would I tell for sure its a 99. It says on paper its a 99 but if what ive been reading is true and 99s dont have perimeter bolt style valve covers then they fucked me over...

**xmarkx** · 10-22-2010, 08:08 AM

it could be a block from a 99.... with 853 heads which came stock on 98's

**SSwt00SS** · 10-22-2010, 08:19 AM

'98 year cars only had perimeter bolt valve covers, from what i have read. they switched to center bolt covers in '99+

**Justin23454** · 10-22-2010, 08:29 AM

ok, so they sent me a 98 and not a 99. Thanks

**Justin23454** · 10-22-2010, 08:29 AM

Originally Posted by xmarkx

it could be a block from a 99.... with 853 heads which came stock on 98's

why would they swap that :O

**xmarkx** · 10-22-2010, 08:51 AM

who knows? maybe they had a block available but it was without heads so they reused your original heads

**SSwt00SS** · 10-22-2010, 09:19 AM

pull the number off the back side of the block and run it. that way you know for sure.

i have a stock '98 TA Ws6 that the older guy i bought it from, he said was stock. however, it has 241 heads. also, my 2000 SS when i looked at the heads were also 241 heads. unless my 2000 SS was produced late in 2000, it should have come with 853 heads i thought (center bolt design). im not complaining, but i understand how questions come about.

im currently working on the TA and will be pulling the motor. ill run the block from there and see what the whole story is. there really is no difference between a '98 and '99 except for the valve covers

anyone can correct me, but this is what i thought the head breakdown was:

'98-'00 = 853 heads
'01-'02 = 241 heads

i have heard that some '98 had 806 heads. i cant confirm this though.

**Marc 85Z28** · 10-22-2010, 10:33 AM

Originally Posted by SSwt00SS

anyone can correct me, but this is what i thought the head breakdown was:

'98-'00 = 853 heads
'01-'02 = 241 heads

853 casting: 98-00
241 casting: 00-02

The switch from the 853 perimeter to 241 centerbolt happened mid-year. Some original perimeter bolt cars had engine service under warranty, and the only service replacements may have been 241 castings.

**SSwt00SS** · 10-22-2010, 10:49 AM

thanks. i was wondering if they changed mid/late year in 2000, apparently so. thanks for confirming!

**Justin23454** · 10-22-2010, 11:21 AM

Originally Posted by SSwt00SS

pull the number off the back side of the block and run it. that way you know for sure.

i have a stock '98 TA Ws6 that the older guy i bought it from, he said was stock. however, it has 241 heads. also, my 2000 SS when i looked at the heads were also 241 heads. unless my 2000 SS was produced late in 2000, it should have come with 853 heads i thought (center bolt design). im not complaining, but i understand how questions come about.

im currently working on the TA and will be pulling the motor. ill run the block from there and see what the whole story is. there really is no difference between a '98 and '99 except for the valve covers

anyone can correct me, but this is what i thought the head breakdown was:

'98-'00 = 853 heads
'01-'02 = 241 heads

i have heard that some '98 had 806 heads. i cant confirm this though.

ok so if I have 241 heads on my old engine, can I just swap them out onto my new engine? And if so what if anything do I need to do to make it work?
Also what is the diff in the 241 head and 853 performance wise or how was the heads improved?

**SSwt00SS** · 10-22-2010, 11:28 AM

that is correct. you shouldn't have to do anything. plug and play. just need to use new head gaskets.

i cannot tell you what the difference is between the 853's and the 241's, performance wise. i don't think there's anything, but someone else will have to answer that.

**Justin23454** · 10-22-2010, 01:26 PM

last question is there a diff. between the 806 and 241? Because ive got the 806 on my new engine.

**Firebirdjones** · 10-22-2010, 02:10 PM

Originally Posted by Justin23454

Also what is the diff in the 241 head and 853 performance wise or how was the heads improved?

The 241 heads went through a different casting process (sand casting??) I forget what it was called. In any event, this provided more consistent dimensions from port to port and also provided a smoother finish.

In the end the 241's had slightly higher flow bench numbers compared to the earlier heads. I have a flow sheet around here comparing them. I want to say there was a difference of 5-10 cfm peak flow between the two.