Beretta.net

I've become very interested in learning more knowledge About how much boost a stock internal 3100/3400/3500 or any combination of the three can handle..

I'm not as interested in opinions as i am the facts of who has done what and for how long.

Vehicle, engine, mods, miles on engine before they boosted, how many current miles or miles before the engine blew and reason for it blowing up, intercooler/aftercooler/no cooler?, how hard they push their engine or beat on it,

This may not be the best forum to ask this on because we mainly deal with beretta's but I'm talking about any vehicle that has any one of the 3X00 engines, I am mainly asking because I want to see what actual proof there is that our engines can hold a certain amount of boost etc and for how long, As well as all of the week links that caused failure.

I'm not as interested in completely forged engines because I know they can handle pretty much any boost you can throw at them, but they can be listed as well

Check daveycavy and 91z24 on v6z24 iirc there both on stock internals but seb (91z24) is building his engine soon. and daveycavy ( david ) is going to up the boost till he blows a 3500

60*v6 is a bit better for this question. Loner666 (corsica) was running 6-12 psi with (basically) my engine and meth injection for a few thousand miles without ever blowing it. Mars on 60* was running 15-18 psi with high octane and meth injection to his 3500. He has blown a few though, never really talks about what fails or why. 3400beretta here runs 3500s as well, I'm not sure how much boost but has broken connecting rods on two? engines. TGP37 on 60* has a 3100 with stock internals and is running ~6 psi. Hasn't broken anything but doesn't have a lot of miles on it and is conservative with his boost. Then there is me.. I have about 4k miles on my build. Stock 3400 with ported 3500 upper end. Been running 6-12 psi and haven't broken anything. But again, not many miles and haven't taken it down the track. I'm likely going to pull it soonish and install my double roller timing chain.

I can't cite the sources, but basically with our 3400s or 3500s if we have excessive detonation (knock), our pistons fail. When the car is tuned well, it seems to be the connecting rods that fail next. Most people are running 3500s now due to the fact that some have forged cranks, all have oil squirters on cylinders 5/6, they outflow 3400s, and how easy it is to find them. If you want to go forged, modified SBC rods fit in 3400s but you need custom pistons due to the fact that the wrist pin is different on our stock pistons vs SBC. Wot-tech offers the rods for 475 and forged pistons for 800.

Im aware of how much and where the items to build an engine can be purchased ect..

I was just like i said trying to find out who has done what and for how long with stock internals..

And i cannot create an account on 60degreev6.. but if someone could start a thread like this over there i can view it..

I can only speak for a 3500 because that's all I've used. I have a well matched T3/T4 turbo with an intercooler. The first engine I blew, I had a misfire/backfire going on, that I believe was ignition related but I'm not 100% sure. I was going down the track and it started popping, and I kept my foot in it. This was probably at 14psi. A connecting rod was ejected through the oilpan. Was #6.

Second engine, I installed a electronic boost controller, and I thought it was working correctly. First test drive out, I stepped on it in 1st gear, glanced at boost gauge and it appeared to be around 10 psi. Shifted into second gear, put it to the floor and felt the car take off like a bat out of hell, before I could get out of it, another connecting rod through the oil pan. Later inspection found it to be the same #6 rod. I would assume the boost spiked up to at least 20psi, as the electronic boost controller wasn't working at all.

Both of the above engines, as well as my current 3500 have the steel crank. Identified by 7484 punched into the crank nose IIRC.

At the track, I have pushed the boost as high as 14psi. I dare not go any higher, and I would say a safe number for driving on the street would be 12psi. Although 12psi on the street is so much power its retarded. Traction is only available in 4th gear or higher.

I have about 2000 miles on my setup with zero knock at WOT running 6-7psi daily, i was just trying to find out safely how high i could go daily based on other's who have actually boosted vs just opinion, my engine is a 3450 hybrid with around 70xxx miles..

And yes i agree, i do not even get traction at 3-5psi when i take off..

I'm running 10psi since day 1 (5 years ago). I really don't have much mileage on it tho. I did blew the same engine 3 times (200-300$ rebuild each time), mainly pistons #4 and #6 and one felpro head gaskets. Only mods to the engine was comp cam 26915 springs.

- First time I broke piston #4, we were just having fun in some back road.
Probably had too small injectors (28lbs/h) and megasquirt 1 with no knock control. I didn't had a lot of tuning experience back then.

- Then I replaced #4 piston/rod assembly with a used one and felpro head gasket, blew an head gasket 300km later.
When I rebuiled the engine the first time, I increased the ring gap to give the ring some room to expand without butting and explode the top of the piston, something bad still happened that made them explode. At that point, I had 36lbs/h injector. Upgraded to megasquirt 2 at some point after that.

- Then my friend was driving it at the track one day and broke piston #4 and #6, video here: https://www.youtube.com/watch?v=FZbzEh6 ... ZZ0RDa15uw
Engine was starting to be really fucked so I got another one.
- Then I installed a "new" 3400 with 38k km on it, still running it. Will get replaced with a mild build 3500 this spring tho. I'm also now running the J&S safeguard individual knock control system as well as the AFR safety feature of megasquirt 3. This is such a simple feature, yet so awesome, it looks like this:



So if AFR goes lean for whatever reason, everything cut, you punch your face in the dash but save your engine

I would say that the limit of those engine in a stock form is much higher then 10psi. I will be honest and say that I had no idea what I was doing in the beginning but did learn A TON along the way while having a bunch of fun, not regretting it one bit!

I did had problem with the walbro fuel pump too (as you can see in one of the pic), one day it decided it was time to start seizing up and I could see the fuel pressure dropping and dropping and barely made it home. When I replaced it (with the same model), I had to retune my VE table because everything was now too rich so something was weird with the pump, probably for a while. The small (too small ?) injectors I used at the beginning probably didn't help either.

I will be swapping the 3500 soon as well as add an EGT thermocouple and water / meth injection.

So some things to remember:
- You NEED a wideband
- You NEED good knock control
- Datalog, datalog and datalog when you're still in the tuning stage and make sure you cover all portion of the VE/Spark table.
- EGT thermocouple is a nice to have
- AFR safety feature is a nice to have too, it catch a bunch of stuff faster then you ever could, but its not bullet proof (might not trigger for a bad injector for example)
- I have a feeling more boost but more rich is safer then less boost but leaner for the same HP
- Tune it right! If you end up with high 13 AFR in boost, get your foot off the gas pedal ASAP and find the problem.
- Water / meth is nice but you have to have safety feature for it because the pump can lock up without you knowing and you're fucked. I'm going to have that as well as being a progressive setup.

Here is the first failure





Felpro head gasket did that mess:



Doorman intake gaskets aren't that great (see middle cylinder)


This is what happened at the track in the video:


Ring gap mostly closed still


Walbro fuel pump messed up


Hope that helps!

Your info is greatly appreciated!

It's funny that you mentioned you had Walbro fuel pump issues Because I did as well, Jon and I were tuning and I never really got into boost because we weren't that far yet so I never really noticed that it would be going lean when I got more into the throttle, But after a while Jon noticed and I pulled the pump and had to drill holes in the canister so that more fuel could get into the pump, And just as you said my VE tune was all screwed up so we had to redo half of it which sucked..

My VE tune is tuned to within 1 to 2% variation from mild driving to wide-open throttle with zero knock on 89 octane thanx to Jon, We were currently in the end of that MAF tune doing WOT runs when the weather went south for the winter, so i had to put it on hold until spring.

Where the head gaskets that you blew regular Fel-Pro or felpro SD?

And I have contemplated about a water/meth injection kit, But never really felt it necessary unless I go to around 8 to 10psi of boost, currently im running 6-7psi, Since I daily drive it I worry about running out etc. on long drives and whatnot or forgetting about it and screwed my engine up I just don't feel it's worth it unless I go to more boost

Not sure which felpro it was, whatever whats in the picture All I know is there is no reason not to get GM graphite gaskets instead. You did pay them a bit more but its worth it. Good valve springs (comp cam 26915 or 26986) are a must, gaping ring for boost can help giving some more for rings to expand in case the tune in not always spot on or in case something goes wrong. It's quite a bit of work to do just that tho but if you are down to the pistons, you might as well do that too.

Yeah, I think walbro are hit and miss. The one that seized never sounded right since day one. The one I have now sounds fine. Oh, fuel pressure gauge is good to have too.

Oh and taking a look at IAT is a good idea too, making sure its not too high, especially when supercharged AFAIK. IAT location is also very important. I had problem of running lean on hot restart and I figured out that my IAT was getting heat soaked and was making it run lean the first minute it was running when the engine was hot (IAT was in the plenum, now its in the charge pipe few feet away from the TB).

My iat is about a foot and a Half from my tb, i barley even noticed my intake temps rise during boost, not sure if its because im aftercooled or not..

Got asked to elaborate a bit more on the J&S safeguard so here it is:

First, their website is: http://www.jandssafeguard.com/. I have the interceptor model. I think I paid around 600$ but can't remember exactly, might be a bit more than that.

The reason I bought this in the first place is because at that point, Megasquirt didn't had any reliable knock control. It's different now with the MS3 knock module but I already have this J&S knock module now. I still think it can be a good buy for people with the stock ECU that already have knock control because AFAIK OBD2 isn't doing individual knock control either. What this module will do is retard timing on only the cylinder that is knocking. It does that in configurable increment for a configurable maximum of degree of retard. I installed a row of LED in the console that make one more LED lit every time the module retard the timing an extra 2 degree. You also have an headphone plug on the module to be able to hear your engine.


Is it worth it ? For me, it definitely was when megasquirt had no reliable knock control and now I will definitely keep it as I know it works really good. For OBD2, the stock system might be enough but this is definitely a bit more advanced.

3400tZ wrote:Got asked to elaborate a bit more on the J&S safeguard so here it is:

First, their website is: http://www.jandssafeguard.com/. I have the interceptor model. I think I paid around 600$ but can't remember exactly, might be a bit more than that.

The reason I bought this in the first place is because at that point, Megasquirt didn't had any reliable knock control. It's different now with the MS3 knock module but I already have this J&S knock module now. I still think it can be a good buy for people with the stock ECU that already have knock control because AFAIK OBD2 isn't doing individual knock control either. What this module will do is retard timing on only the cylinder that is knocking. It does that in configurable increment for a configurable maximum of degree of retard. I installed a row of LED in the console that make one more LED lit every time the module retard the timing an extra 2 degree. You also have an headphone plug on the module to be able to hear your engine.


Is it worth it ? For me, it definitely was when megasquirt had no reliable knock control and now I will definitely keep it as I know it works really good. For OBD2, the stock system might be enough but this is definitely a bit more advanced.

Yeah I've heard it's not really necessary with an OBD2 engine, But I can't see how it would really hurt.

Got a pm from MarsMan on the cavi site..


I dont have a login over there, feel free to post this up for me.

Quote:
I blew up 2 motors in the Camaro, the first was a 50$ 3400 that I got from a friend, It made wierd noises from the get-go and had molasses oil. It was in a very neglected minivan and was not by any means an engine I was planning on using for any amount of time. It was more for mockup. I don't even think I "wasted" money on putting Synth. oil in it, I just ran cheap stuff cause I knew it was coming out. #4 con rod bearing was done, rod was loose, pistons all looked fine. That thing ran some high 7's in the 1/8 mile with a 59mm 60-1/T3.

The second engine I blew was a 3500 and as mentioned it spun the cam dowel off and lost timing. MAY have been caused by not using Loctite and proper torque on the bolt. I'll never know ... ? pistons / gaskets were all perfect, cept the damage from hitting the valves, lol, but the ringlands were fine, ect..

It had survived PLENTY of 15 psi jaunts. That was tuned at 11.50 AFR on 91 octane. Never had head gasket issues with it, even using the stock torque to yield bolts and GM gaskets. I'm guessing around 50 1/4 passes and about another twice as many 1/8 mile runs.

Now I more recently blew up another 3400. (this one had ALOT of use) link for that one here : 200 passes on that engine EASY.

http://60degreev6.com/forum/showthread. ... he-Vee-s

And, actually, now that I think of it, it's possible I blew up another high mile 3400 WAY back in the day when i was just startting to tune my Rotrex cavalier setup. Lost an intake gasket adn chocolate milked the oil. pistons were fine, though, it just didn't make any more oil pressure...That was an OLD 3400, like a 1999 one. They had shitty all plastic LIM gaskets, and head gaskets back then.

Nowadays, with the steel LIM gaskets and the graphite head gaskets, we are much better off.

And let's get something straight, my cars / engines are ABUSED all the time, they don't have it easy. I race ALOT.

I think they are stout motors. Would run 12 PSI on a 3500 all day long with a good tune.

AS Seabastien said : DO NOT USE THE DORMAN INTAKE GASKETS, go with GM...