what is good on a first gen engine (91-92)?

[crazy_quick]

Just wondering if there is anything better on the first gen engines then on the second gen.

[Igovert500]

The gearing is better for the 1/4 mile on the first gen 5spd vr4s, than the 6spd vr4s....Also the first gen ECUs are ALOT easier to datalog and monitor for knock...but that is more the transmission and ECU rather than the engine. As far as the engine...I can't really think of anything that would be more desirable from the first gen over the 2nd. However, there isn't anything wrong with the first gen engines, simply Mitsu improved them over time to handle power better. Many of those changes don't really matter unless you are planning on more than 500hp...but nonetheless, they are improvements.

[crazy_quick]

whats the deal with the '99 lifters, are they better?

[Linebckr49]

1st gen engines have a 2-bolt main, whereas 2nd gen engines have a 4-bolt main.

Yes, the 99 or 3rd gen lifters are better than the 1st, 2nd gen lifters. The design for the 1st/2nd gen lifters is simply poor as it does not allow sufficient oil lubrication around the top of the lifter (see www.3sxperformance.com , section engine uppper for more). 1st/2nd gen lifters are not, however, bad in any way. They still function properly. Sometimes you will here a ticking sound from the engine...this is the infamous 'lifter tick' that plagues all 3000GT/Stealths...some have it, some don't, some will get it. Lifter tick will not harm your engine, its just an annoying sound. The only reason to upgrade to 99/3rd gen lifters is to get rid of the ticking noise, but before taking such an exepensive route, try chaning your oil, maybe oil additives, and different oil filters. 3sxperformance sells 3rd gen lifter for 400, but dynamic racing sells em for 300.

[Thourun]

Originally Posted by linebacker49

1st gen engines have a 2-bolt main, whereas 2nd gen engines have a 4-bolt main.

So what exactally does that mean, I've heard about it but not precisely what it is and what practical difference it makes.

[Igovert500]

2 vs 4 bolt:
Read:
http://www.stealth316.com/2-2bolto4bolt.htm
http://johnmonnin.netfirms.com/4bolt.html

And here are pictures of the difference:
http://johnmonnin.netfirms.com/4boltPictures.html

[Thourun]

Thanks! Pics and reading material what more could I ask for.

[Igovert500]

Originally Posted by Thourun

what more could I ask for.

Half naked girls....free beer....and a vr4...although I don't know how well I could provide you with all of those...

[Thourun]

Yea I guess theres alot more I could ask for but like you said I ain't gonna get it from you lol. So the 93 had the 4 bolt and tougher crank?

[Hotshot8792]

91s and the first half of 92s have a cast crankshaft and cast rods and a 2 bolt, and an 18-spline transmission

the second half of the 92s and newer have forged crankshaft and forged rods and a 4 bolt, and a stonger 25-spline transmission

all cars came with cast pistons

1st gen's have 5-speeds
2nd gen's have 6-speeds

the difference in horsepower is a restrictive nipple that came in the 1st gen boost solenoid, which can be easily removed to match 2nd gen horsepower

although its just better to buy an $18 mbc and a aftermarket boost gauge


as far as N/A's, all n/a's have 2-bolt blocks, but the cast to forged internals changed with the vr-4s

[Thourun]

Thanks that was very helpfull! So how does one tell wheather they're looking at a 92 from the second "batch"?

[Linebckr49]

Originally Posted by Hotshot8792

as far as N/A's, all n/a's have 2-bolt blocks, but the cast to forged internals changed with the vr-4s

i'm a bit confused. i thought all cars from 92.5 on had the 4-bolt mains, according to your post. but did this only apply to VR4s from 92.5 on? Also, when looking at John Monin's explanation http://johnmonnin.netfirms.com/4bolt.html , he says that in order to determine whether you have a 2-bolt or 4-bolt, simply look at the type of CAS (crank angle sensor) you have. On my 93 3000GT base, i have the latter type of electrical CAS, mounted next to the timing belt cover.

So are all NAs 2-bolts, or do i have a 4-bolt?

thanks

[crazy_quick]

So what is so good about a 4 bolt compaired to a 2 bolt?

[Igovert500]

Did you read the links I gave...