Difference between the years

[MuRCieLaGo]

Hi guys,

Is there somewhere I can find the differences between all the years? Especially for the front bumper... I searched just a bit, I thought it would be easier to find.

Thanks!

[Kevin]

91+ has the same bumper

[Dynomite]

Hi guys,

Is there somewhere I can find the differences between all the years? Especially for the front bumper... I searched just a bit, I thought it would be easier to find.

Thanks!

The differences in body style are one thing.....the differences in LT5 engines by years are another thing :p
You can mix and match parts but you have to know what the differences are so you do not change functions while mixing and matching ;)

I have even detected a difference from a few of the first 1990s (#72 for example) to the last 1990 sold to public (#3032).

Differences between 90', 91' and 95' Crate Engine Plenums and IHs (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-6.html#post1583614819)

[Paul Workman]

IIRC, installing a 92(?) head under my 90 IH results in a double restriction; one in the IH, and the later mo. head. I thought about it at the time and decided there was no issue with the redundancy. For 5+ years and 20K miles, it hasn't mattered, far as I can tell.

[We Gone]

There were more changes in the interior over the years than the body. Button tag colors changed from orange to white with some of the functions changing, LCD changes, seats, door panels, dash, console, rear storage boxes.

[Dynomite]

IIRC, installing a 92(?) head under my 90 IH results in a double restriction; one in the IH, and the later mo. head. I thought about it at the time and decided there was no issue with the redundancy. For 5+ years and 20K miles, it hasn't mattered, far as I can tell.

Great information Paul......you are one of few who have the double PCV restriction (90' Injector Housing PCV Restriction and 91' and later Heads PCV Restriction). You are also one of the few who have thought about removing the stock PCV restrictions in the 90' Injector Housings
to avoid the Double PCV restrictions in the 91' and later Heads AND 90' Injector Housings.

PCV Differences between 90 and 91 Injector Housings (http://www.zr1.net/forum/showthread.php?p=102911#post102911)
Differences between 90', 91' and 95' Crate Engine Plenums and IHs (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-6.html#post1583614819)

[Paul Workman]

Great information Paul......you are one of few who have the double PCV restriction (90' Injector Housing PCV Restriction and 91' and later Heads PCV Restriction). You are also one of the few who have thought about removing the stock PCV restrictions in the 90' Injector Housings
to avoid the Double PCV restrictions in the 91' and later Heads AND 90' Injector Housings.

PCV Differences between 90 and 91 Injector Housings (http://www.zr1.net/forum/showthread.php?p=102911#post102911)
Differences between 90', 91' and 95' Crate Engine Plenums and IHs (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-6.html#post1583614819)

Considering the question of "mix n match", ponder this:

Is there any proven advantage or disadvantage for eliminating the injector tip bosses in the IHs? e.g., when porting, the 90 IHs primary port boss is typically eliminated in all the 90 IHs I've seen, and it doesn't seem to do harm the performance (that I can tell). In fact, I believe by removing it one could easily argue a small increase in flow, due to less restriction; often touted as an advantage of porting the 90s (not making that unproven claim myself, doanchaknow...).

[Paul Workman]

For a more comprehensive list of changes, goto the Registry Home (http://www.zr1netregistry.com/Information/General/ZR1Trivia.aspx) page and look at ZR-1 Trivia under the INFORMATION tab. Lots of good reading there, but there were other subtle changes as well, in the cabin an "creature features" departments, in particular. :cheers:

[MuRCieLaGo]

I'll continue my reading on the main page, thanks Paul and thanks to the other guys here!