VK45 –Stage 1 Headers/JWT cams/TB/intake
- Thread starter Logan
- Start date
TB install still causes engine to run poorly out of the box. Not sure what the issue is other than the TB internals being tweaked during dismantling OR the engine needing to be dialed on the dyno OR the engine needing more (or less) of something else to compensate For the bore flow. Exhaust is TIGHT, better than ever, header collectors have been pulled and redone where needed. Front is lower still and now has 35mm spacers (brand new 25mm spacers will be up for sale soon BTW), slight tuck but rubber is right on the liner, very happy with stance until I hit a corner under speed and run over a pot hole =).
Arrived in Seattle last night. Drove the FX tonight for the first time since it went back in the shop. 35mm spacers in front are tight but W/T's still tuck and are very close to flush, with entire family in the car there was no rub and the ride - excellent. Still can't get over how dialing in the pre-load, having the right spring rates, the correct tires and the GT specs all back in place makes the ride firm yet compliant. Very sports car, but not harsh at all. No smell in the cabin, exhaust note is just right and power is good, getting either tune done or wheels clear/tint coated this week.
Update: Ran another tune today. Last time the shop had to quit half way through the tune due to tranny overfill issues. Best run today was 294/303. Tech discovered that one of the engine sides was running hot and determined that the heat build up has been affecting performance, cooking the plugs maybe more. Determination by tuner and builder - During pervious improper dyno runs (when the engine was running dangerously rich) the one side cat loaded up with unburnt fuel heated up and some of the cell walls slagged up. I need to replace that HFC or go test pipes. I don't want to go louder so its 1 or 2 new HFC's pita BUT this comes with the promise of an increase in power and even smoother performance. Tuner didn't have time to try the bored TB but he feels confident he can make it work. Next tune.....
---------- Post added at 10:00 PM ---------- Previous post was at 09:58 PM ----------
BTW - the additional 23 HP and TQ gained over the last run is very noticeable.
---------- Post added at 10:00 PM ---------- Previous post was at 09:58 PM ----------
BTW - the additional 23 HP and TQ gained over the last run is very noticeable.
I don't know that HFC's will make that much of a difference in sound, as opposed to adding other pieces as mentioned above. I put the HFC's on my midpipe purely from an emissions standpoint. It's still loud as hell. Although I heard the same exhaust on a Z without the HFC's (although it was 3') and that was fingers in your ears loud.
HFC's in the stock location make a bigger difference in sound. The further back you mount HFC's or resonators, the less effective they are at reducing sound. Exhaust velocity drops as it gets further from the engine and that changes the noise. But maybe put some test pipes in until they get all the tuning done? It would suck to fry another cat. Or if you're not already, run lower cell cats. Less effective for emissions, but less chance of clogging up too. I know some use 200 cell cores and some 300. You could go as low as 100 cell, but it wouldn't pass emissions if you care about that. You could probably get new cores welded into the existing HFC. May be cheaper than buying all new ones.
In conversation with the tech he said that the v8 will definitely generate a considerable amount of noise less the HFCs, he also said the system would generate more power. The FX is my daily, in this situation I don't have a choice and need towards keeping it quieter if possible (it already rumbles at idle and under low rpms).
Sending me mixed messages Nick, is it Goof numbers or do you think the progress is good?
thanks man, you can drive it now or wait for the fox and the TB but its so much more fun than when I first got it back and so much smoother....
Sending me mixed messages Nick, is it Goof numbers or do you think the progress is good?
Ha. My flat fingers and phone keyboard = fail