Hey everyone, Been lurking for the last few years... Been thinking and planning a new build since I sold my Formula back in 06'. A question has come to mind and I'm curious what others think.
Are high hp builds worth building without transmission options to put the power to the pavement? The 4T65e-HD is limited by the chainset, and since the 1" GMR chain is out of production and rare to find used, even at $2k. What to do? 7/8 and 15/16 chains have all had issues. Granted they will hold for a while but it would be better to have something more reliable.
Only other option would be to stretch the chassis for a better transmission setup.
I will say this.....not having a 4th gear limits the high end MPH on my 350 swap I just got. its fast.....but it tops out at 120. sucks!!! I got a beefed T125 stock trans that does the trick. for how long? not sure but when it gives I plan the upgrade for sure
[This message has been edited by batousai666 (edited 08-31-2014).]
It depends on you; if you love to dump the clutch or hold the brake with an automatic to do burnouts, well.... I have an 86GT 4spd, intercooled turbo with lots of other mods. And also have an 87GT 5spd normally aspirated that's fully built for high RPM, whereas I can refrain from doing wild burnouts - they look dumb anyway with only wheel smoking- I have not had any problems. Too bad there are no good posi-rears available for the Fiero.
The transmission has always been the weak link in a high-horsepower/high torque Fiero application. That being said, my mildly built TPI SBC Fiero with a bone-stock 5-Speed Getrag held together for several years of very spirited driving before finally letting go at the dragstrip. Again, THE DRAGSTRIP. Meaning, the transmission would have probably lasted a lot longer behind the torquey V8 on the street if I didn't let myself get curious about 1/4 mile times at the track. The fragile Getrag didn't stand a chance even after what I considered to be a mild launch out of the hole. That said... it was stupid of me to even try, but I figured if I was gentle off the line, the transmission would be ok... wrong, wrong, wrong! They just weren't made for that much of a torque load.
Automatics are a different story... they obviously have a much better track record.
I think this subject is pretty broad and there are lot's of factors to consider. A person can spend a lot of money beefing up their Fiero transmission for more horsepower and torque, and still end up breaking it if it's overly abused. From my experience, I say go ahead and build your high-horsepower SC 3800, SBC, LSX, etc Fiero UNLESS you absolutely, positively, HAVE to abuse it and/or race it all the time. If those are your main priorities, then maybe it's time to consider a getting RWD muscle car instead of a Fiero.
[This message has been edited by ITALGT (edited 08-31-2014).]
As power level increases, there are many fiero parts that will start to fail from time to time, especially if you run drag radials and focus on 1/4 mile performance. The key is do you enjoy the car in between these failures? One aspect of this enjoyment is the cost to fix the failure. If you routinely frag a $3K transmission, that's going to be much less enjoyable than snapping a $50 axle shaft every now and then. If it takes you 6 months to save up to fix the failure, then the car will sit and you will have near zero enjoyment with it.
My 382whp LS4/F40 has been rock solid reliable for the last 14K miles and has seen twelve 1/4 mile passes + lots of other WOT upshifts. Part of my good results is I don't run drag radials, so my ET suffers some, but it improves reliability. The nearest 1/4 track is 2 hrs away, so its not very high on my priority, but one of these days I will get a set of drag radials and try to break something.
As you look at the Fieros with over 600 fwhp, you see lots of input shaft failures (4T65), chain failures (4T65), transmission failures (4 speed/282 getrag), axle issues (more so on manuals), clutch issues, flywheel issues, differential issues, etc. But most of these guys/gals are running drag radials and chasing 1/4 mile ET and a certain amount of parts breakage is to be expected when you are running at that power level.
I really enjoy reading Justin's updates on his 3800 Turbo/F23 setup that has over 800 whp. He gets a lot of respect from me as that thing is a beast, he maintains a positive attitude about the failures, and is always willing to put it back together and beat on it some more. His failures help us better understand the weak points of various components and for the most part his failures have been "relatively" inexpensive.
My old Formula with a 3800sc2/getrag, headers, CAI, 3.4 pulley and tune put 250whp / 282ft/lbs. I think for this next car I want to at least double it. So to answer the define high hp? I guess for me, for this application... it would start at 500whp. I have spent months trying to track down a 1"GMR chainset with some of my old GM connections, needless to say it would be easier to find a unicorn. It pays to play... but I'm just looking to try to minimize the fatalities along the way.
Any experience with ZZP trans.? Or have most gone with TripleEdge?
Are high hp builds worth building without transmissions that can hold up?
Well, IMHO no... "It's funner to drive a slow car fast than a fast car slow" anyways. Based on a lot of experience ($$$), if starting over I would clearly state the desired goals for the car: HP/TQ, 1/4 ET, twisty track champion, etc... Start there and then come on the forum and ask what's the best way to get there from cost/labor of love standpoint. If not sure, get the most built up drive-train you can up front and build the internals of the engine you want to use up front so as your skill as a driver and budget for bolt on power adders increase you don't have to drop the cradle in the future...
My $.02 anyways...
Also, the reason I went with the N* was b/c of the near indestructible 4T80 that came with it...
Everything comes with a cost, consequences of modification, and change of driving habits. If your smart enough, you can build a project car that fulfills dreams, and goals. The biggest problem with this thread is that everybody is different in the respects of what they want to achieve, their dream goals, and finally budget.
A very important thing to remember, is that mid-engine street cars along the sports car line, were never intended to do high rpm clutch dumps on a manual transmission vehicle. Neither was boosting the HP/Toque more than 3 times the factory rating, durability is going to suffer. Talk to True Hot Rodders and they don't complain about part failures, it's expected. You find limitations by experimentation, and everybody has a different approach of what they want out of their car. The real key to this is understanding what the limitations are in your particular case, once you understand those limitations, do not exceed them in any of the items mentioned above. In addition there are different formulas for 1/4, Road Coarse, Show Car, Weekend Driver, Daily Driver, etc.
I think a lot of people mis-understand high horsepower builds. My swap is of course just one of many, but I dyno'd 315rwhp and roughly 332ft/lbs of torque. Now in terms of high horsepower, I like to think it's just an all around great setup. High horsepower, not really, but in terms of street driving and track times, it works exceptionally well. You can have so much fun and not have to worry about things breaking and run some really great times. My setup ran 11.7 and it can beat literally any car from a stop on the street and maintain gas mileage in the upper 20's. The transmission is always going to be something you have to decide on. If you want an automatic you are interested in more launches, track visits and reliable driving. If you want the feeling of a manual setup, downshifts, hard launches are going to be the end of that transmission no matter what. It's not a good setup for any car at the track realistically. It can work though, but the 4t65e-HD transmission has been the best overall setup for higher horsepower Fieros. My recommendation is find what you want, remember that your driving habits make up 60-70% of the longevity of the setup. I've learned that no matter what, a failure of some sort can occur in a modified setup and there is no reliable situation 100% of the time. If you want that, you should buy a Honda Civic.