Just my luck...

[IsaacHayes]

ewww thicker oil. Slows me down and makes my valves chatter

How far did you port down when you did the 75mm TB? I doubt you got it all the way into the center of the plenum, but a funnel affect would have been created regardless so it still probably forces more air in.

[Superdave]

i went in the length of the neck iirc, then it tapers back to the oval shape..

so far the RP has quieted down my valvetrain noise, i'm going to drive it to work and back tomorrow and open it up a little to see what happens..

[gectek]

so you had valvetrain clatter as well?

[Joseph Upson]

You're runing 13 sec quarter miles on a worked 3500 that a balance job and compression increase to around 11.5:1 might turn into 12.5 sec quarters on pump gas and Fiero owners are still turning to the 3800 SC, cadi 4.9 and 4.6 Nstar and small block chevy and still struggling to break into the 12s having spent as much or much more than the cost of building up a budget 3500. Cam, valve springs, DIY porting, home made headers and you have a performer.

I don't understand why anyone would want to put a naturally aspirated 3800, or 3.4L in a Fiero with the aluminum head fwd engines available.

One thing is certain, torque doesn't necessarily win races as much as it does get you out of the hole quick, after that the high end engine will pull longer and delay shifts, kind of like only needing to shift to second gear for a 0-60 run instead of third.

You have to turbo that thing and if you do a "thing" is exactly what it would become. It's so efficient up top that 7 psi would probably take you all the way through 12s down into the 11s, unless as I mentioned before, it snatches the front end off.

[RedBird]

man o man..... as much as i'd liek to see dave's car in the mid 11's with a turbo, his cam is SOO not meant for that... Dave, how many degree's of overlap do you have? let's just build some headers and turbo my car instead i bet with 10psi i could touch 11's before i broke it.....

[gpse3400]

Not to whip it out but yeah I had a 3400 that wound out to 7200 on an automatic W-Body which was years ago. With that said I am plenty familliar with it, not to discount the select few people on this board,(two members/pioneers of which are not really active right now) who have graciously helped me to get it there.

The combination of beyond extra power and exceeding the operating range without a balance will cause failure and it could be any part. A couple 100 rpm the factory nominal and maximum engine speed would actually be enough to do it as you are now taxing the design. Swaping the rod/piston right there you've upset what balance you had and longevity to 100K is even less not there. Not to menion any structure flexing of any part that is happening at 7K under that load. With a balance not only will you run way smoother and keep the crank and rods from banging around in the bearings, you also gain more power and less spark trigger scatter. You would be right to do so. 2nd I never said you were running an HV HP pump, I said that if you were to it would NOT fix the problem nor would any oil or additive off the shelf. 3rd the cam bearings would've been good to check because that vibration does transfer, also the heavy valve springs loads up the cam bearings and you might've damaged those as well..

But if this is all a toy and you aren't relying on it then it doesn't make a whole hell of a difference.

[Superdave]

Not to whip it out but yeah I had a 3400 that wound out to 7200 on an automatic W-Body which was years ago. With that said I am plenty familliar with it, not to discount the select few people on this board,(two members/pioneers of which are not really active right now) who have graciously helped me to get it there.

The combination of beyond extra power and exceeding the operating range without a balance will cause failure and it could be any part. A couple 100 rpm the factory nominal and maximum engine speed would actually be enough to do it as you are now taxing the design. Swaping the rod/piston right there you've upset what balance you had and longevity to 100K is even less not there. Not to menion any structure flexing of any part that is happening at 7K under that load. With a balance not only will you run way smoother and keep the crank and rods from banging around in the bearings, you also gain more power and less spark trigger scatter. You would be right to do so. 2nd I never said you were running an HV HP pump, I said that if you were to it would NOT fix the problem nor would any oil or additive off the shelf. 3rd the cam bearings would've been good to check because that vibration does transfer, also the heavy valve springs loads up the cam bearings and you might've damaged those as well..

But if this is all a toy and you aren't relying on it then it doesn't make a whole hell of a difference.

Aah.. i see what you were saying..

I never swapped out the rod/piston.. I measured and checked the rod that spun the bearing and it was fine, there was minimal damage to the surface but after a very close inspection i went ahead and tossed a spare bearing into it and slapped it all back together. The crank journal surface cleaned up easially with some 1K grit sandpaper, i checked it for roundness and overall diameter and it was within spec as well. I cleaned out the oil hole for any debris and slapped it all back together with some good assembly lube.

I'm going to drive it all weekend and most of next week to shake down any problems before it goes to the track on the 19th... Plus i want to empty the tank out so it's lighter on the track. my 13.08 run was on a full tank of gas



Damon, with the 3500 manifolds you have an oppertunity to do one helluva turbo setup. If you buy all the parts we can build the setup on my car this winter then transfer it over to yours. Or i still have that spare 3400 block and Dustin's heads that could be tossed together on a stand if you want.

Yes, no way i could boost the car on this cam.. 70.45 degrees of overlap. I'd need to get one of Ben's boost grinds.

[gpse3400]

To quote the great Leslie Nielson..."Good luck, we are all counting on you." BTW N/A FTW

[Joseph Upson]

Yes, no way i could boost the car on this cam.. 70.45 degrees of overlap. I'd need to get one of Ben's boost grinds.

It's not the camshaft overlap that serves as the main limiter for turbocharging, it's your exhaust flow efficiency with the turbo. On any given turbo platform, if you increase the exhaust flow efficiency thereby decreasing the exh/int pressure ratio, you can increase overlap or decrease the LSA.

Simply put, an exhaust pressure to intake pressure ratio under boost equivalent to 1:1 is neutral, you shouldn't blow an air-fuel charge out the exhaust and no exhaust should back up into the intake. This is the reason a supercharger camshaft is somewhat different than a turbo camshaft although both are pressurizing the engine, only one has the potential to directly affect exhaust flow.

A good header design and proper size turbine housing for the boost level and overlap will not be a problem. I have a video of a turbo mustang staging with what must have been at least a 1000 rpm swing up and down it had so much cam. The car nearly took the tree down it launched so hard as the torque twisted it towards the right lane.

It's about 3.5 mb in size I can send it if you'd like, it's one of my favorites.

[1988GTU]

A good header design and proper size turbine housing for the boost level and overlap will not be a problem. I have a video of a turbo mustang staging with what must have been at least a 1000 rpm swing up and down it had so much cam. The car nearly took the tree down it launched so hard as the torque twisted it towards the right lane.

It's about 3.5 mb in size I can send it if you'd like, it's one of my favorites.

Send me that shizzz.... PM sent.

[IsaacHayes]

Me too. (my name) at gmail dawt com! Thanks!

[1988GTU]

Gots it! tanks!

[3400-95-Modified]

My valvetrain is somewhat noisy too... I think it may be due to running fully stock lifters tho, I'm not sure. And it may also just be piston chatter... I hate 3400's piston slap.

[gpse3400]

That is because your cam is very aggressive and you are moving the valvetrain quicky. There is really nothing you can do about that, short of noise abatement or just not running a cam with such an aggressive profile. Reasons for the factory not to use agressive cams other than the engine idling bad(to the avereage person) and expelling a higher amount of emmission, is the valvetrain clatter that cannot be masked. It is not detrimental. just something you have to deal with.

[RedBird]

i've got some icky valvetrain noise too. nothing i'm too worried about, but it's shitty going downtown and i can hear it loudly when i pass parked cars..... going to switch to some 10w40 oil i think on my next oil change(5w30 right now, only 2k miles into my first full-length oil change so far)

Dave- i never even thought about your car being down for the winter..... that'd be some sweet shit right there. but i only have one set of flanges for those manifolds. i think it'll probably be N/A for long enough that i'll just make up my n/a downpipes and exhaust with them :P