N/A stock compression 3.1

[streetdreams]

what kinda power numbers do you think are attainable with a 3.1 n/a 10:1 compression. I think it would be cool to build up a 3.1 or 3100 with some performance ideas running on 87 pump gas. anyone seen any engines running along these lines?

[Guest Gp crazy]

well you may see a little add hp but it's going to be really small. may be 5-10 or so. you find you need 89 or higher to run it.

[Robby1870]

well you may see a little add hp but it's going to be really small. may be 5-10 or so. you find you need 89 or higher to run it.

 

Na, the key to making power with higher compression is a cam that supports said compression ratio, heads and intakes that will flow enough and tuning.

[streetdreams]

I think 10:1 is low enough to run 87 octane. running a cam is gonna sky rocket the gas and thats what I'm trying to avoid thru 87 pump gas

[THe_DeTAiL3R]

3100s have more power and get better fuel economy than series II 3.1s ...

[z284pwr]

umm, if your looking for performance, fuel economy should be the last thing on your mind....and the octane rating of the fuel isn't going to change anything about the gas mileage

[Prospeeder]

3100s have more power and get better fuel economy than series II 3.1s ...

 

isnt the 3100 the series 2 3.1? like, the 3.1 MPFI, then the 3100 2 (160hp), then the 3100 series 3 (185hp or so) then the line died

[manitcor]

there were no 3100s that put out 185hp, your thinking about the differences in the 3400 in various appications.

 

I always thought the gen 1 engines were the early carbed and tbi 2.8s gen 2 was the 3.1 MPFI and the gen 3s were the 3100/3400 gen 4 is the 3500/3900

[Nick1234]

3100 made 175hp

[THe_DeTAiL3R]

The first 3100s had 160hp, the newer ones (late 90s) with the bigger letters on the plenum put out 175hp.

[excelsior]

if your going to run a 3.1 setup i would eithier go the tgp route, OR swap a 3100 and do enough mods to get it to around 200 hp(about all you can do realistically) and swap into a j body.

[gp90se]

I doubt your going to be able to get a 3.1 to run on 87 with 10:1. our 385 fastburn crate motor (much better flowing heads) and stock smooth cam pings with anything under 91, and its only 9.6:1, now run that sucker on 91-93 octane with a good tune, port/polish/valve job, larger cam, and a modded upper/lower intake, I dont see why 270 horse isnt possible

[EurosportZ34]

if your going to run a 3.1 setup i would eithier go the tgp route, OR swap a 3100 and do enough mods to get it to around 200 hp(about all you can do realistically) and swap into a j body.

 

:withstupid:

[z284pwr]

I doubt your going to be able to get a 3.1 to run on 87 with 10:1. our 385 fastburn crate motor (much better flowing heads) and stock smooth cam pings with anything under 91, and its only 9.6:1, now run that sucker on 91-93 octane with a good tune, port/polish/valve job, larger cam, and a modded upper/lower intake, I dont see why 270 horse isnt possible

 

Umm, you do realize that carburetor vs. fuel injection comes into play here right.....there is a HUGE difference there....the 455 in our Trans-Am has upwards of 9.5:1 compression or so and it pings with less than 30* of timing, and the TGP has a 9.5:1 compression with 12psi and it doens't ping at all or knock or anything like that

[gp90se]

if thats a stock TGP motor, its running 8.7:1 compression. I do know the EFI makes a difference when it comes to pinging with compression, but it isnt by much. The highest compression ive ever seen run on 87 was 10:1 on a honda motor, but that has an entire fuel system setup and tuned for it.

[z284pwr]

if thats a stock TGP motor, its running 8.7:1 compression. I do know the EFI makes a difference when it comes to pinging with compression, but it isnt by much. The highest compression ive ever seen run on 87 was 10:1 on a honda motor, but that has an entire fuel system setup and tuned for it.

 

http://home.earthlink.net/~z284pwr/beretta/engine.jpg

 

No its not a stock TGP motor, which I though was 8.8:1 not 8.7:1? Oh well yeah your right it doesn't make "that" much of a difference, and a cam can also change or hide the compression ratio too. My cousin has a built 383 in a '79 Camaro with a huge cam and has right around the same at the 455 in the Tran-Am and it has no where near the problem with pinging and can run a lot more timing, a carb can also affect that as well I have discovered thanks to the 454 in the Suburban, yes there are lots of things that can affect it. And yes your right, being able to tune for it helps ALOT, having a Haltech has taught me quite a bit about that....

[streetdreams]

Z284pwr wrote

"umm, if your looking for performance, fuel economy should be the last thing on your mind....and the octane rating of the fuel isn't going to change anything about the gas mileage"

wtf does that have to do with my question, other than shooting me down what were you trying to add? I want to run cheap gas to keep the car affordable as a daily driver, and using high octane isnt gonna do that now is it? I found out theres quite alot I can do

if I have the time

[z284pwr]

wtf does that have to do with my question, other than shooting me down what were you trying to add? I want to run cheap gas to keep the car affordable as a daily driver, and using high octane isnt gonna do that now is it? I found out theres quite alot I can do

if I have the time

 

Well when you had stated the 10:1 compression part, usually raising compression is related with performance. Why would you have a raised compression engine and be looking for economy/affordable daily driver? I guess i got lost in the point at that point and with everyone saying the key to perfomance with raised compression, my bad :oops:

On topic, here is what I would probably do. Start off with a 3400, they are some 9.5:1 compression as it is if I remember correctly, then if your really going to tear into it, maybe a regrind, nothing major, just something to help it breathe more, maybe some better valvetrain component to maybe help with some high RPMs if your going for that. Then of course your simple good intake and exhaust that won't require higher octane and will even help with gas mileage.

[streetdreams]

sorry man, ya anything under 10 but above 8.9 is fine with me. my focus is gonna be low end torque since I feel that is the only strength of this motor other than durability

[THe_DeTAiL3R]

You should feel the torque of the 3500.. holy shit (I can't wait to get inside something with a 3900 V6 ) In a bloated Montana SV6 I was able to easily spin both tires loudly for a solid 5 seconds- better than any of the 3400 Grand Ams we have on the fleet. It's like a friggen hot rod minivan...

 

The only way to get serious power out of a 3.1/3100 without spending mega bucks on machine work and custom internals is to boost it.

[streetdreams]

I really dont know anymore. I see very few people with succesfull boosted 3.1's.

piecing togethor a TGP can be a expensive nightmare from what I know. the machine work in my area really isnt that expensive at al (if/considering you got the pieces for nothing/cheap) I think carburating and opening up the airways is worth considering

[THe_DeTAiL3R]

I think the best you are gonna do by machining a 3.1 is to get it running as strong as a brand new engine, depending on how far you go you might get it in the 16s but still gonna get whooped by just about everything else.

 

Also if you were to carb it (which I dont think is possible anyways as a direct bolt on) I think you are gonna have to chop a hole in your hood cause I don't know if there would be clearance...

 

I know you're thinking of something different but the best would simply be a (newer) 3x00 top end swap. But hell even the 3400 Grand Ams aren't that fast and they're a smaller car, and you wouldn't be putting out as much power due to less displacement.