Rebuilding 7 bolt.. Budge build, this could help all of us.

[my98GST]

I'm picking up a 7 bolt that needs to be rebuilt, no CW. I don't really have a whole lot of $$$ to just throw around with so I was thinking about going with my 1g big rods and 2g pistons.. Reguardless at how you look at it, the 1g bigs will be a lot better than the dinky 2g rods.

My question is with proper tuning, proper hardware (i.e. arp head studs ect ect) how much power could you safely get out of this before you would have to worry about bending a rod? I've searched around and have only found recommended psi for the 1g bigs..

 

[90TTalonAWD]

there is the stock 7bolt putting down 450 to the wheels, i don't see why the big rod combo couldn't take it even further. Safely tuned, 400 whp is a sure thing as long as the fuel and boost is there to make that power.

 

[FORMONTOYA]

I'll agree, a stock 7 bolt bottom end should have no problem with 400WHP if properly tuned and maintained.

 

[my98GST]

Now here is a big question that I have..... I know that 2g pistons would have to be machined on to the 1g rods... Roughly how much does this run? Just a ball park figure.

There have been a few people tell me that the 1g big rods wont fit on the 7 bolt crank...

 

[Splitpi]

Now here is a big question that I have..... I know that 2g pistons would have to be machined on to the 1g rods... Roughly how much does this run? Just a ball park figure.

There have been a few people tell me that the 1g big rods wont fit on the 7 bolt crank...

I have to comments that are of my oppinion, so believe if you will or not.

1) You have GST so anything past 350 hp will make it very difficult to drive as a daily driver when fully boosting, so that means your will stay within the max capabilities of stock bottom end.

2) 1G big rods will have to be machined at the crank side to fit the 7 bolt crank, along with special fitting the bearings. In my oppinion, the cost of having the 4 rods modified to not only fit the 2G pisons and 7 bolt crank is more expensive than buying already properly sized aftermarket rods.

So in my oppinion, unless you envision 400+ hp stay with the stock rods and pistons (I'm assuming its a 2G 7-bolt block you are using (ideally) and not the less ideal 1G 7-bolt block which does not have the crank angle sensor. Just have the bearing replaced, block disassembled, hot bathed, re-hatched, new rings, ARP studs installed, BS removed and new oil pump, all new seals and gaskets.

 

[my98GST]

well I've got a set of m/t et slicks on some bogarts so thats why i was wondering.... So a basic 7bolt rebuild and proper tuning could handle around 350 on the motor reving to around 8500? even with a small say 30-50 shot of nitrous with water injection? Nitrous used only on occasion..

 

[chrisfullwood]

any amount of power is always possible, it all depends on what you want to do and how you do it.
the most important thing is regardless of power to find the weaknesses of the block and setup, which if im not mistaken with the 2g 7bolts it is the tendancy to crankwalk, and make sure that those weaknesses dont happen. 400hp isnt good if it isnt going to hold. so spend your money on bulletproofing the block and you may only get 350hp, but it will be reliable. compared to someone else 450hp block, and watching his engine blow itself up.

 

[Splitpi]

well I've got a set of m/t et slicks on some bogarts so thats why i was wondering.... So a basic 7bolt rebuild and proper tuning could handle around 350 on the motor reving to around 8500? even with a small say 30-50 shot of nitrous with water injection? Nitrous used only on occasion..

The key is the head work on that and the tranny.... Upgrade the valve guides and springs with more aggressive cams.

 

[my98GST]

Yes i know that... I've got a 2g head getting ferrah valves, BC springs, retainers, bronze guides, new seals, and 280 cams.... getting either a magnus or JMF im..