245 bhp on a 3.1/3400/3500 hybrid-possible?

[Superdave]

I thought that the 3400 valves would hit the 3.1 wall or not be within spec. Either way, not worth the hassle since the 3.1 is flat tappet and the oiling system isn't that great. Plus, what about using the 3400 roller rockers, isn't that going to be a problem? So you'd have to probably swap the stamped rockers onto those heads right?

It must be 3500 you are thinking of. the 3400 and 3.1 combustion chambers are about the same width. lots of people have built hybrids with that setup.

the 3400's roller rockers work fine, you just use custom length pushrods to get the correct geometry.

[1988GTU]

I remember a while back when I questioned it, I was told that the largest top end I could fit on a 3.1MPFI is a 3100 top end without problems. Must have been too far ahead in thinking on my part to expect a narrow answer at that time.

[no_doz]

the turbo is an interesting thought, what kind of power do you guys think a 3100 could make with the appropriate tb, turbo headers, good tune, hypereutectic pistons, arp rod studs & shot peened rods could make at 8psi with mild porting?

also, will a 3400 LIM & 3500 UIM work on a 96-98 3100?

[1988GTU]

246 left front wheel horse power in 78 degree Fahrenheit, 41% humidity, 5.36 minutes of run time, 7.8 mph winds coming east, and 92.944 octane. That is just a rough guess.



lol

[robertisaar]

think of it this way: at 8 psi you're pushing in around another 1/2 of an atmosphere.... so about a 50% bump in torque compared to a identical engine without boost...

[IsaacHayes]

2000+ 3100 and 3400 share the same heads, so the 3400 heads will work on a 3.1 bore no problem.

Boost, a lot of power. lol

3400 LIM, 3500 UIM on a 96-98 3100. YES. It will even work on a 94-95 3100 granted you grind the LIM to clear the stamped rockers. If you have notches in the head and can swap to roller rockers or have roller rockers from the get-go (96ish+) then you are good to go.

[no_doz]

out of curiosity do you guys think 240 crank hp with no cam or increase in compression/no power adders-would be possible out of 96-98 3100 with 3400 LIM & 3500 UIM, long tube headers, bigger tb, & moderate porting all around & a good tune?

[IsaacHayes]

Figure a big port 3100 is 175, the 3500 UIM and 65mm TB won't get you a whole lot. The TB a little, the UIM, not much peak but a broader power band which is nice. Headers probably around 20-25 crank. I'd say you could get over 200 but I'm going to say no to 240.

[no_doz]

with a good crank scraper-10 crank hp, porting 5-10 crank hp, tune, good intake setup for it? seriously the porting, tune, crank scraper, & intake setup wont push this past 200?

[Superdave]

10 HP from a crank scraper? hahahaha....

[60dgrzbelow0]

I'm sorry...But I just dozed off in a "No Doze Zone"'... Do you have modifications right now in any combination similar to the 'recipes' you are suggesting here on your machine(s) ? If so...how about a few pics ...or vids ...or something...?

[pocket-rocket]

Build whatever you want... Make up the difference with NOS, YO!

[ForcedFirebird]

All that work and you want to refuse buying a cam?

Ben had a customer get in the 220'sWHP with a 3400, that would be about this 245BHP you mention, so expect a little less with a 3100 - but you aren't going to do that without a cam! CAM! CAMMMMM!

[no_doz]

honestly, i have absolutely none of these modifications (although i do have a pretty conveniently setup set of headers for a 4.0 I6 that are ready to be re flanged & tweaked just a bit to suit a 60* app).

while piss poor as i currently am, ive been doing my best to find out as much info as i can about the different 60* engines to figure out which one i would buy/build/swap into once i do have the funds.

im most likely not going to get to build more than one or 2 (one for me, one for the woman), so ive been toying around with all kinds of combinations to see what would suite what im looking for best considering power constraints, gas mileage, & cost effectiveness.

LX9 3500 FTW, i just got on car-part & there are plenty of them for $3-500 in running shape! thank god for car-part because before it all the 3500's i could find were $800 atleast & i can get a whole damn 3400 trans sport or 96+ 3100 w-body with serious trans or otherwise problems-for $200-$350, so the way i saw it-the $500 saved could be used to compensate for the difference in size with the right parts.

F that-3500's are cheap enough, forged crank (right?) plenty of flow, & better gas mileage than the 3100 or 3400 cars-so LX9 it is!

[Superdave]

Until tomorrow when a new topic shows up..