351w turbo build.... Turbo guys teach me things...

Kid wita 5oh

I'm definitely not in the original hole
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Nov 5, 2000
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Ok so after blowing up my stock block 347
--Scat rotating assy(cast crank)
Tfs 170(originals not 11r)
Ported gt40 tubular
Xe274hr cam
Vortech v3 Si (3.125/6.8x pulleys)-

1st main bearing spun, snapped crank just in front of 2nd main.

I'm going to a 351 swap..... Selling the vortech and going turbo
Setup will be budget-ish..
-stock bottom end, low ish miles
-Promaxx project X 210 cc. Heads
- same 274 cam
-single plane EFI intake(torn between budget eBay manifold and Tfs r series)
-Throttle elbow and 105 mm throttle body(got them super cheap so it's what I'm using )
-hot side kit I will actually spend some money on from pony down performance
-on3 intercooler(build my own plumbing)
-cheap 7875 turbo

Running holley termX, with 80lb dekas. And will be going to a coil near plug setup with this swap

Now for my actual question... This is 100%a street car, will NEVER be raced that I MAY put 1000 miles a year on.... this is also my first turbo build for a gas engine.
I want this to spool EARLY (2500-3K), I'm not concerned with high rpm...6500 max rpm...

Ok here's the question ... The turbo is available with a .81 or .96 at turbine ....my gut tells me the .81 is the right choice for my use but I don't know.. will the .81 choke it out before 6k? Will the .96 spool too slow (over 3k)?

Damn this was long, I'm sorry

And what do we think on the eBay single plane ?
 
Flange & HP target? What trans? If auto, how loose is the converter? Gasoline?

Based on your explicit street car, low RPM comments, I probably would opt the way you're already leaning, towards a lower A/R that really lights off fast. But, turbo systems are often a trade-off, and this is one of those cases. You'll spool 400 rpm faster, making it a fun street car, but you will have high back pressure limiting power production, especially if pushing higher boost or more RPM. At least that's consistent with your cam, which will also target lower revs. The only inconsistency is the single-plane selection, which would be a higher RPM play. I'd go with a long runner, personally, but if you're stuck on the elbow + carb style, both if which will hurt driveability & low end, I'd be looking to see what the dual plane options are.

And look, at the end of the day, if you decide you're unhappy, it's just a turbine housing away from trying the other option. I know you're budget-minded, but honestly, it's probably a perfect wash if you pick up a .96 and sell off your .81.
 
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T4 flange, OLD school tko until it breaks then a tkx

I Don't have a specific HP goal .. just something silly to run around in (I know that sounds childish... Midlife crisis maybe?)

As for the single plane and low rpm driveability... I've heard that, but I've also heard it isn't really a problem. Engine masters did a video about it at one point and I've seen others too...
I dont know, but I'm going with it
 
The ebay manifolds aren't as refined as the name brand ones they try to copy. Will it work? Yes. Does it make less power? Also yes.
That manifold is the same one you get from AcesEFI. They'll sell any of the components you need, or a full kit. The intakes apparently work well enough that they keep selling them. They don't seem to know too much about the height, though. I'm trying to clear a stock hood and they couldn't really answer how tall their setup is. Apparently nobody in the building knows how to read a ruler. But keep that in mind. If you do have a stock hood, the 351w doesn't want to make it easy on you.

If you decide you want to run with a ford EFI setup, I do have the 351w intake and fuel rails and all that crap I just pulled off mine.

Does your 351w have an oil pan compatible with the fox? I just spent $300 on the conversion pan/pickup/dipstick.
I've done the 351 swap before, 20+ yrs ago. So i know all about the fitment hurdles
Drop mounts and k member spacers are coming to help.

You can get the pan cheap....same one that Ford puts in the swap package
 

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Then, in that vein, I'd say the A/R won't matter to ya, either. It's going to spool quick enough and make good power for a street car, either way.
 
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