Differences between the 88 and 90 years of the 7MGTE Block and Crankshaft?

[927mgtepat]

Hello guys, I got a couple of extra engines laying around and am trying to find out which are the older style 7MGTE and the newer ones. I have heard that the 7MGTE cranks have extra counter weights. What are the differences on the blocks? Some of the blocks that I have, have a stronger looking cradle and extra supports on the out side of the block, is this the 90 style?

 

[IJ.]

 

[927mgtepat]

Thanks IJ. But which one is which? Also am i right about the cranks? What is the better of the two blocks for High HP?

 

[IJ.]

Pic #1 and #3 are a 92 block #2 and #4 are an 87

92 block is at least 2mm thicker everywhere so much better and don't seem to suffer the deck cracks like the early blocks.

Top pic 7M bottom 6M

 

[Mr.PFloyd]

the one which is thinner, and has less ribs is the pre 89.
WITH MY LAST BREATH, I CURSE IJ!

 

[tekdeus]

Wow, quite a big difference. How common are cracked early 7M blocks? What are the causes of this?

 

[IJ.]

Tek: Ummm quite common and they're about 2mm too thin in places

 

[upgradedsupra]

I am happy to say, 92 block FTW! :naughty:

 

[927mgtepat]

Thanks IJ, did they ever put the 6M crank in the newer style block? I got a newer style block with a 6M crank in it.

 

[IJ.]

NA's got the heavy block before GTE's did (Group A race motors are cherry picked NA blocks)

There's a lot of confusion as to when all the changes happened so it's possible.

The above 87 block has 18K miles on it and is cracked in a few places.

Only problem/Issue with a late block is a lot of core shift at the foundry so before trying a monster overbore I'd have it Sonic checked to make sure there's enough wall thickness (but you'd do that anyway)

 

[927mgtepat]

Thank you very much IJ, that helped out a million!!!!

 

[turbodriz]

I am looking for one of the newer style blocks. Are use saying that nobody knows what year they actually came out. What is the difference betweem the na and gte block?

 

[IJ.]

NA = no squirters and it's not drilled for the Turbo drain and the extra knock sensor.

Jeff Lange may be able to pinpoint exactly when each was released.

 

[Doward]

'91 block here!

 

[turbodriz]

NA = no squirters and it's not drilled for the Turbo drain and the extra knock sensor.

Jeff Lange may be able to pinpoint exactly when each was released.

Who is Jeff lange?

 

[IJ.]

Ummm he would be Jeff Lange

 

[927mgtepat]

I have two Newer style blocks. PM if you want one. Plus a built short block that is on eaby right now

 

[turbodriz]

pm sent.