taking the 3.1 to the limit

[project89]

well the car has performed awsom at only 9 psi running 13.008 on a tune that was off by a decent bit on the fueling 10.0-10.5-1 afrs.

so we got the tune fixed and afrs are were they should be car should now go into the low 12's @ 9 psi buttttttttt,thats not enough for me

so we didnt have a proper wastegate spring so we shimmed mine the gate cracks open at 14ish psi and dosent fully open till aroun 23 psi.

so were going to make some high boost runs even if my gate dosent provide 21+ ill just put a few turns on the boost controller to bring it that high.
in preperation for this i just ordered a 10gph meth nozzle

now im on the stock crank and rods still u guys think im gonna break the crank with boost that high?

whats the highest anyones gone power wise on stock crank and rods

[3XTurboAgain]

my buddy was running 18 psi on his 3.1 for a little while before the piston blew. the meth will definatley help you keep the motor together tho! I dont think you'll break the crank, id worry about the bearings and pistons, maybe youd break a rod after a while.. Sounds pretty awsome tho!

[project89]

im not to worried about it breaking i have a shortblock ready to go if this one fails.
as long as it dosent damage my cam or heads if it lets loose lmao

if she holds together i may be tempted to pull the heads off and do a half fill with some block filler before taking it back out again.
sproly something i should have done when i assembled the motor knowing how hard i was going to push it when i built it.

by the time its all said and done i will prolly have pushed this thing to around 30 psi of boost

[1988GTU]

Good luck! I someday look forward to being in the 30+ psi club.

[TurboGTU]

Keep it under 7Krpm and it'll be fine. I think only problem you'll run into is gasket fail from too much pressure. Need to put the HD felpro gasket or o-ring the block. Theres the issue of mains shifting about the 350hp+ but havn't heard anything like that on thise engines, only the early small main engines. Also it'll be wise to harden the surface of the crank if it sees alot of track and street use. Helps keep the bearings and crank happy at those load levels. Don't need block filler unless your pushing way past the 500hp mark. Even then, you'll trade off the cooling affect unless its a drag only car. You'll need a steel crank past 450hp anyway as reliability goes down the tubes with the stocker. More early if your a lead foot, rev alot. So 350hp max on the stock crank, rods. Reliability I guess.

Some people change out bearing as insurance on max effort engines every so often since they see alot of abuse.

[project89]

well considering im already over 305whp which works out to what around 380 crank @ 9 psi
i do rev above 7k my shift points are just shy of 7,500

im working on modifying my crossmember to make the center section removable to make it easy to service the bottom end of the motor with it in the car.
though it really wont matter with the head studs if the heads ever gota come off im gonna have to pull the motor out neway

i quess its time to start looking into crankshaft options
luckily crower sponsors out alky dragster so maybe i can get a nice crower crank cheap somehow
i think the crower crank was 1k last time i checked iirc

car is a street car but the direction its heading in is track/sunday cruiser, i really hate climbing in and out of camaros with rollcages

[Superdave]

find a 7484 casting crank from a 3500. they are forged steel. you could offset grind the crap out of it and build a stroker as well

[project89]

yeah but that would cost way to much money, by the time i got the crank and pistons

deff cost more then a crower crank and a set of hbeam rods