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400hp on stock internals?

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Racah15

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Discussion starter · #1 ·
So I've heard, but is it really true when you come down to it?
I have heard of people bending valves, blowing pistons rings, and just totally killing their engines. I have a stock 7bolt auto (so not too worried about crankwalk)
Could I really be pushing 400hp with just basic upgrades. (ofcourse all the supporting mods, but I don't think injectors, Safc, etc are as "intense" as cranks, valves,pistons,rods, etc.) Just the supporting mods and a FPt28?
Also what is better for this range (350-400hp) MafT w/ gm MAF or the stock MAF?
 
#2 ·
400 wheel horsepower or crank horsepower?

I'd say it's possible, at least with a 6-bolt. Your 7-bolt may not be quite as durable. You will need ARP head studs eventually to avoid lifting the head under high boost.

The S-AFC will have trouble controlling injectors larger than around 650cc, so DSMLink would be a great upgrade, although you will need an EPROM ECU.

The stock 2G MAF will work fine for power up to maybe 500.
 
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#3 ·
Sure it's possible, but who knows how long your internals can reliably do so. Regardless of crankwalk, 7 bolt rod bolts aren't all that great.

Something bigger than a t28 sounds a little more realistic for your goals.

A 2g MAF can handle alot, but a GM MAF is less of a restriction. I agree with the previous post about DSM Link. It's worth what it costs and is better than a MAFT if you go that route.
 
#4 ·
I would like to jump in and ask a question about what you guys are recomending, with the GM MAF cabel and DSM Link what else is needed to remove the 2GMAF. how does the system work, I have research a bit but still dont understand.
 
#5 ·
I believe the only version of DSMLink where you don't need a GM MAF Translator is v3 (now called ECMLink).

The GM MAF is often harder to tune with than the 2G MAS.
 
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#6 ·
Even though the stock 7bolt internals aren't as hefty as 6bolt internals, the 7bolt block is still loaded with potential. I've got a friend that is somewhere around the 500hp range on a stock 7bolt bottom end. However his car isn't just basic upgrades, it is upgraded and tuned to the absolute perfection. 400 crank horsepower definitely isn't anything unheard of with these engines.
 
#7 ·
It all depends on the tune. If your car is seeing lots of knock, but you aren't doing anything about it, you are going to blow the motor long before a properly tuned car would.
 
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#8 ·
It goes to say, "Fast, Cheap, Reliable, Pick Two." 400hp is getting to where you gotta pick between cheap and reliable. To be completely honest, have you thought about your tranny? Can it hold 400 crank hp, or 400 wheel hp? For how long?

The biggest problem we run into as a community, is we can make stupid amounts of power relatively easily, then we constantly shred our driveline parts. Yes, the 7 bolt can make that kind of power with a few modifications, the bottom end can take it, but, what about everything else?

Edit: If your engine is 100%, then the power is no problem. Most problems we end up with as far as the engine goes, is bad tuning, and not following the manual to the tee when engines are rebuilt. Spinning a timing belt when it has 160,000 miles is one thing, improperly installing it is another.
 
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#9 ·
cAPSlOCK97gst said:
I believe the only version of DSMLink where you don't need a GM MAF Translator is v3 (now called ECMLink).

The GM MAF is often harder to tune with than the 2G MAS.
Click to expand...
This is correct. Harder, initially yes. But once you dial the GM MAF in, it all becomes the same as anything else. I recommend doing ZERO...

ZERO

Tuning with the maf-t unit (for those with dsmlink) itself and you will be fine.

400hp is indeed possible on stock internals. Even a 7 bolt. You will need head studs probably at minimum. I would do rod bolts as well. You will need to dial the car in for absolute consistency in all conditions and avoid ANY knock WHATSOEVER. Which means you probably won't be pushing it out of that little T28. If it were an old FP KILLER 28... maybe... but even then probably not without race gas / or methanol injection.

You just cannot afford ANY hiccups at that power level on a stock engine. You are dealing with cast pistons, OE rings, press fit pins... and stock rod fasteners... Good? Absolutely... going to take a bunch of bullshit? No fucking way. I had a bad detonation event on a stock 7 bolt bottom end @ 28psi and it blew a piston into puzzle pieces and bent every fucking rod in the motor.


I wouldn't even ATTEMPT a run at 400 WHP on a stock 7 bolt without the following;
-ARP head studs
-ARP rod bolts
-DSMlink
-Quality core FMIC
-Water injection
-EvoIII 16g / 50trim <bigger
 
#12 ·
hand1222000 said:
400HP on a 7block is possible but will not last long. I've seen a stock Longblock 6bolt do 520AWHP on a FP3065. And still is running strong and lasting in everyday traffic.
Click to expand...
7bolt will take it for a while, assuming the tune is good and the motor is in good shape.
 
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#14 ·
It all depends how you drive. If you have a good tune, and dont boost at every traffic light i beleive it could last a long ass time. 7 bolt or 6 bolt. If your not dogging it it will never take a shit on you. But if you go WOT all the time, then ya nothing will last that long.
 
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#15 ·
fanaticdsm-er said:
It all depends how you drive. If you have a good tune, and dont boost at every traffic light i beleive it could last a long ass time. 7 bolt or 6 bolt. If your not dogging it it will never take a shit on you. But if you go WOT all the time, then ya nothing will last that long.
Click to expand...
True Very true! If you baby it the engine will last longer and normal oil changes will help that. But all in all the 7 bolt is a good engine just gets put down to much because of the crankwalk issue.
 
#16 ·
Even though it is possible, why would you do it with the VERY minimum required parts?

Yes you can do it, but I hope you have a few grand coming your way because your drivetrain would need expensive upgrades. If I ever did something like that I would be nervous everytime I got on it.

I would recommend doing it right. Get a ride in a 400hp dsm and you will understand why that is not a good idea!
 
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#17 ·
Racah15 said:
So I've heard, but is it really true when you come down to it?
I have heard of people bending valves, blowing pistons rings, and just totally killing their engines. I have a stock 7bolt auto (so not too worried about crankwalk)
Could I really be pushing 400hp with just basic upgrades. (ofcourse all the supporting mods, but I don't think injectors, Safc, etc are as "intense" as cranks, valves,pistons,rods, etc.) Just the supporting mods and a FPt28?
Also what is better for this range (350-400hp) MafT w/ gm MAF or the stock MAF?
Click to expand...
On a T28, 400 h.p. is not happening unless temps are below freezing and tuned within an inch of your cars life. Stock MAF will be fine, I see ZERO power difference when switching between a 2g MAF to no maf & speed density. Aside from being forced to install ARP head studs, I haven't had a problem YET running 380-440 h.p. on a stock 7 bolt. The question you have to ask yourself is: "How long will my tranny & clutch survive".
 
#18 · (Edited)
400 wheel can be done on a 7 bolt. As stated earlier there are things you need to address. People tend to want that kind of power, yet want to do it on a 16g or smaller. You have to keep the EGT's low. This is what makes bigger turbos so great, with good intercooling, a bigger turbine will have a lower EGT output. An added bonus is lower output temps and less psi necessity due to higher cfm output. As we all know, keeping that air charge cool is the way to avoid detonation. Run cooler spark plugs, run increased fuel pressure, conservative timing but slightly more boost. Octane is something else to take into account, running 93 is the minimum without meth injection. Done right, the motor can take it.

Secondly, is your drivetrain upgraded. Do you have a strong clutch, do you plan to launch your car, do you pre-load your drivetrain, are you running quality fluids in your transmission, and or diff and transfer case? Finally, what is your social status in life at this point? Is this you only car, do you have a decent job? Obviously if you are 18 and this is just a fun daily driver (but a daily none the less) it would be foolish to test the limits. If a failure isn't the end of the world and your car is more of a toy, then by all means test the waters.

The problem to me however, isn't the power. It's really that even 400hp is a tease to me. Its the very reason I'm making a habit to build a motor this summer. Cars are getting faster by the day, and 400 won't satisfy you for long. I say to hell with stock to begin with, go big or go home. If everything wasn't going to hell, I'd feel more comfortable dropping the hammer on a motor build. I'd rather wait till things settle out a bit more before I do that.
 
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#19 ·
By the way, since it's an automatic in question, you should probably look to IPT for parts/advice/bullet-proofing your transmission.
 
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