Are you giving up on the 3.4 PR?? Come on Lou!!! You are my inspiration dude!! One of the things that I made me do my 3.4 is that you never lost hope!! Come on man!!
LOL I think you are confused. My 3.5 will be a 3400 block bored to 3.7" with iron heads. 3.4 and 3400 pistons are similar but the 3400 pistons have a deeper dish...as do 3500(non-VVT) pistons. Hence I will use longer rods and shave down the top of the pistons to lower the dish dept to compensate for the longer rod. 2.8 flat top pistons can support .510" of lift and luckily, there is a roller cam available from WOT-Tech with that lift.
Longer rods will increase dwell-time near TDC. Allow for a higher revving bottom end as the angle of rod deflection is reduced.
LOL I think you are confused. My 3.5 will be a 3400 block bored to 3.7" with iron heads. 3.4 and 3400 pistons are similar but the 3400 pistons have a deeper dish...as do 3500(non-VVT) pistons. Hence I will use longer rods and shave down the top of the pistons to lower the dish dept to compensate for the longer rod. 2.8 flat top pistons can support .510" of lift and luckily, there is a roller cam available from WOT-Tech with that lift.
Longer rods will increase dwell-time near TDC. Allow for a higher revving bottom end as the angle of rod deflection is reduced.
Oh ok! LOL. I was going to get longer rods for mine but I decided not to. I have .533 lift on mine with DOHC pistons and the crown sticks out of the deck about .050 or so and I don't have a problem with interference. My 2.8 had flat tops and I had .512 lift and never had a problem either.
^^^ That's good to know. I'll be using 3.4 F-Body pistons, which have a slight dish on top (about 0.1" deep). So that should give lots of valve clearance!
After this I discovered someone had regapped my plugs back to .060 hence the misfires (are down to .050" now) and I also made some adjustments to lean out the top end some more but I haven't had a chance to go back to the dyno yet to "record" the results. Though the axle-snapping performance is telling...
What is the torque setting? I've heard 200# and 100#... But part of the problem is the Arraut bearing isn't "right" where the spline doesn't go 100% thru it due to a spacer that is required...
Originally posted by Will: Have you had to work to tame lift-throttle oversteer?
I'm using the same HELD kit, slalom front with bump-steer correction in the back except now 13 years later my front "heim" joints are loose as a spruce goose... Alignment is straight. I just play with tire pressures. Lower on the inside, rear is 23 and 28 psi.
My front end is more of a problem... I need to replace the heim joints that hold the pivot bar of the upper arms... That's the only thing preventing me from hitting turn 3 at WOT right now... Rear end is planted pretty damn good.
My front end is more of a problem... I need to replace the heim joints that hold the pivot bar of the upper arms... That's the only thing preventing me from hitting turn 3 at WOT right now... Rear end is planted pretty damn good.
Sorry for no direct updates in a while. The car may have 1 last race in it for this season in October if:
I only have valvetrain issues that can be fixed before then. On the Memorial Day race of this year, the track was wet and I over-revved the motor on both launches. 2 weeks later when I had brought it back to the track the car had a noticeable power loss. It now seems to be running on 4 cylinders. I am hoping it's just a valve-train issue that can be fixed. In the meantime I have started building up a 3.5L build but waiting on the custom pistons and rods from La Fiera.
The other thing I am trying to fix is the handling. The rear HELD bump-steer correction arms are old have the heim joints are worn which is why I've been spinning out in turn 3/4 when driving hard rather that sliding out like an '88. I ordered some parts from Grainger: 20F989 male rod end, RH, 3/4-16. That is based on information another ARRAUT rear bump-steer kit owner gave me. They need to be un-tack-welded and hopefully these are a perfect replacement and eliminate my wiggly behavior coming out of turn 2 and into 3 and 4.
So the car will be down another month. In the meantime I am adding some coil-overs to my red 3800SC-auto car so that may show up at the track again soon. F40 -> 4.9 swap is pending as well.
Those 1.4" ID exhaust ports are incredible! Did you also do the custom mod to the middle intake??
Do you think you are now upper Intake limited? I guess the MPFI straight-shot intake must be quite a bit better than our stock, distributor-avoiding upper, yes??
It came with the used 3400 engine. It may hit our cradle and will probably get removed during the installation. I believe the donor was a 2000 Oldsmobile w/3400. It's 3.5L now. The machine shop was putting everything back on from the 3400 and I had to stop him. He had the 3400 water-pump on as well. I clipped that out of the pics... Ordering all new Fiero hardware.
[This message has been edited by lou_dias (edited 09-06-2023).]
New build is finally getting closer to being done...
6" rods, custom pistons with 3.7" bore; titanium valves 1.8"/1.5" and a higher revving cam with ~.550" lift
Take some extra axles to the track because you'll go through them much faster now with that engine combo. Ask me how I know! And I don't know what clutch disk you have but a sintered iron disk would be perfect if you want to soften the punch on take off and be able to do it over and over. For your kind of racing I'd use a solid hub iron sintered clutch. You can slip it, dump it, etc and it will take the abuse. That way you don't look so predictable to your competitors. Can't wait to hear it roar!
There are individual Volkswagon gaskets I can use. There's also a larger gasket that comes with 3.4L Summit Headers that fit well.
I used the VW exhaust gaskets as well. (not sure if they're available in Stainless Steel) But I got these copper ones with the 1-5/8" hole that people were recommending. (4 in a package)
It's only once I got them that I noticed the stock exhaust gasket and heads only have a 1-1/2" outlet anyway. 1-1/2" rings also available - could have also used those. All installed - no leaks. YAY!!
It's going in! Finally! And it didn't take 15 years!
Wow! I just noticed this. Your passenger side driveshaft has some sort of support bracket with bearing... rather than I guess what the other Fieros have, which is an absurdly long driveshaft which can probably get somewhat easily unbalanced. This is pretty cool... was this custom, or is it specific to the transmission you're using?
