I know that the 3.1 is almost the very same motor as the 2.8, my question is this! The 3100 from the newer gm car's put out more hp.

I have been told they are a lot more advanced than the older 3.1's. Is the advancments they made why no one here swaps them inplace of the 2.8s?

I would just think that the power increase from the 3.1 to the 3100 is a lot better if your not going to the 3.4 or larger.

I looked at some pictures and even with it being a Fwd it looks almost just like our 2.8's and our 3.1 in our Fbody's!

Anyone care to shead some light on this question for me?


Thanks
Donnie H.

 

The 3100's might look similar, but trust me, they're VERY different and swapping to one would be completely not worth the time invested. Among the differences in the 3100's as opposed to the 3.1's, I believe the 3100's got higher flowing aluminum heads, where the 3.1's still use the old cast iron heads.

 

yeah I figured it was something like that, I had friends when I was younger that had a 94 Cavalier rs conv. with the 3.1, and a 91 Beretta Gt with the 3.1 as well both was the 125 3 speed auto's.

My sister got a 96 Corsica last year with the 3100 motor and the 4 speed trany, I must say boy oh boy, sad as it sounds her car would run rings around my friends cavalier on the highway. and her car was higher mileaged than even the 91 Gt. I never cared much for the Corrisca's till she got her's. They are ok for family car's I guess (hey its a GM car!) of course its ok might not be pretty or flash but hey it say's Gm all over it!



Donnie H

 

corsicas kinda had this reputation for being crap cars. Had a Lumina LTZ w/ a 3100 in it, strong little engine , pulled that car like a freight train, but definately not worth the hassle of a swap into a RWD car.

 

3100 =

9.6:1 cr, with MUCH better optimized quench area
splayed valve aluminum fast burn heads (I hear somewhere around 40% better flow than our iron heads)
1.6 roller rockers (pedestal mount)
roller cam/lifters

That's mainly what's different.

I've got a 3100 sitting at the shop, that I'm tearing down - the heads are going onto the Turbo 3.1, with Turbo GP pistons + 4340 H beams, for 8.6:1 cr, and I'm going to do my damndest to get the roller cam/lifters into the rwd block!

If I can do that, and regrind the roller camshaft, I expect about 180hp/200 tq with a set of headers - and that's BEFORE 12 pounds of boost get shoved down the intake!

 

Good grief, Doward.. couldn't you have come up with that info BEFORE I sold my soul to someone's engine swap in trade for 2.8 heads?

Let us know how it goes.. I'll probably be right behind you if you come up with results before I'm done reworking these heads.

 

There's a guy on the s10 boards put 3100 heads on a bored 3.1.
It required the use of the 3100 intake and DIS ignition since there is no provision for a distributor. He also needed custom pushrods. Like you he has a turbo!

Here is a picture of his Blazer:

http://www.domesticcrew.com/raven/Ja...0FPG%20loc.jpg

 

I'd build a custom intake from mandrel bends and sheet metal due to my strange desire for brute low end torque, but it's nice to see it can be done

 

raven use to post over here tell someone pissed him off, then he left.

I do like the blazer though

 

Then....

How much HPs has the 3100 Lumina LTZ 1997?



Denis V.

 

not a clue, if i gave a guess, it'd just be the a guess....maybe 160-170.

 

160Hp@5200
185@4000

They still call them 3.1's on edmunds, but if you look back at right before they killed the 3.1's off you will notice that the best i have seen by far the 3.1 rated at from factory is like 140Hp@4200 and the Tq is 185@3200

94 Cavalier Z24 3.1

http://www.edmunds.com/used/1994/che.....6.Chevrolet*

97 Lumina LTZ 3100

http://www.edmunds.com/used/1997/che.....6.Chevrolet*

Donnie H.

 

hum, possible 20hp gain from heads and intake?

 

I was thinking the same thing as well Dale!

My sister's car (hate that kind) but it runs great and has been a great car so far has 175k now and we have replaced the idle pulley,Rad,Alt. and she's done basic maintance to it when its due per the owners manual plus a few extra maintance around the side to make sure its in great shape. I have to say her car will run really well. I would race my 2.8 Fbird with 76k with it as I know she would totaly blow it off the road. Maybe if I had a 5 speed it might be a better match.

Her car seems to do very well at the highway speed's I figured when she got it that with it being the AOD it would wimp out on the open highway a little after driving the 3.1's with the 3 speed 125's

I am sure GM has tweaked a lot more than just the heads and intake, maybe not a lot of tweaking, But I bet they did other small things to the 3100 as well to get the 20Hp Gain's from it. I didnt like the loose in TQ I saw with the 3100 tho.

I have seen some 3100 a newer model at someplace on the web thats rated at 190-195 Hp from factory, I am still not too for sure I belive it tho, as I cant recall what it was in and all to go back and research into it deeper.

I thought the 3.1's was killer when I had my first chance to drive one (had a 95 Escort Gt 5 speed then) so of course the 3.1 in a 91 Gt would seem like a Corvette.

Now I have to say I like the punch the 3100's give a lot better. My sister's car (she dont know this and wouldnt ever do it either) But on the smooth Okc roads(few and far between) if you take off from a stop sign or stop light and leave at WOT when it kicks from 1-2 will spin and chirp the tires, I was impressed, I had a Maxima that would do the same as well. Think that depends mostly on the smoothness of the road a lot tho.

Donnie H.