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holley + turbo


Old 10-23-11, 01:51 AM
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NJ holley + turbo

hello all im still new at rotarys and was wondering. my vehicle came with a holley 600cfm , is it to complicated to add a turbo ? i must mention its a 12a motor and the carb is a holley i read somewhere it can be done but they didnt explain what was needed to do this . id love any input on the subject and thank everyone in advance. also the holley seams to be to big of a carb at idle i get a really strong slightly burned fuel smell and after a little down shifting after some spirited driving i get a horrible sulffer smell . i have a cat and a resonator aswell as a muffler the pipe is a 2 1/4 inch dia, do i need to go for a smaller carb or will (if possible) a turbo help out in burning the raw fuel? oh and this is the funnest car ive ever owned. now i want one of each gen. damn i hate being poor . thanks again in advanced , p.s really realley want to turbo this car and unleast the monster inside
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Old 10-23-11, 02:33 AM
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Heh. If you think the size of the carb has anything to do with how much fuel is delivered, you're a long way from being ready for a project like this. You'll have to learn all the aspects of how a carb operates, because you'll mostly be on your own as far as tuning (though at least Holley information is more readily available than Weber information). If you're serious about attempting this, here's some stuff to help you get started:

How to boost-prep a Holley style carb:

This forum is the best place to search for blow-through carb related information:

A while back I put together a partial parts list for a friend wanting to do a blow-through 12A in his B-series truck, which I'll repost with some modifications here:
- Turbo
- Exhaust manifold (if you make it yourself, make sure to use .120” wall pipe, which you can get from Racing Beat)
- External wastegate if your turbo doesn't have an internal one
- Exhaust system (at least 2.5", 3" is better)
- Carb hat (you can buy these for Holley carbs from various places)
- Intercooler and piping
- Blow-off valve (I don't know how necessary this actually is, but it seems like a good idea)
- Air cleaner assembly
- EFI fuel pump (I suggest a Walbro 255, but any good inline EFI pump should work)
- Larger hard fuel return line is recommended, though you might be able to get by without it
- EFI-rated soft fuel line
- An appropriate fuel filter (EFI type after the pump, or one of the clear carb types before the pump)
- Mallory 4309 or similar boost-referenced return-style fuel pressure regulator
- Fuel line fittings for said regulator
- Fuel pressure gauge (Autometer now makes an electric one with a 0-30 PSI range, which would be perfect)
- Wideband, boost and water temp gauges at minimum
- Boost controller (manual or electronic, your choice) if you can't change wastegate springs to regulate boost
- Vacuum lines of various sizes (for BOV, boost gauge, FPR, boost controller, etc.)
- 1/4” or -4 AN turbo oil feed (you'll need to drill and tap your oil filter pedestal or use a gauge block for the oil feed)
- Depending on your turbo, it may need an oil feed restrictor
- 5/8” or -10 AN turbo oil return with a fitting for the front cover or oil pan or wherever you decide to put it
- Water lines if your turbo is water-cooled, and a way to plumb them into your cooling system
- You need to lock your distributor, or if you feel like getting creative, limit its mechanical advance to 10 degrees or so
- Some sort of leading ignition upgrade is recommended (FC leading coil with an MSD or Mallory 6AL would be a nice setup)
- Oil cooler upgrade since you have an '84, probably a radiator upgrade as well
- Probably other stuff that I forgot

Important note: your Holley MUST be a mechanical-secondary double-pumper carb. Vacuum secondaries DO NOT WORK in a blow-through setup, and Holleys don't like ghetto-rigged mechanical secondaries like Nikkis do.

So, short answer: yes, it's complicated to add a turbo.
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Old 10-23-11, 02:43 PM
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i have bin doing holley carb turbo +12a setup for some time now..it is a pain in the *** . changing jet every time the temperature drops 10 degrees.......do yourself a favor a save up for a turbo2 s5 engine..
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Old 10-23-11, 05:13 PM
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Actually, unless you can do everything yourself and just pay for parts and materials, a TII swap is usually cheaper.
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Old 10-24-11, 10:54 AM
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ive been building my turbo 12a for a year now... just an FYI. Its not a weekend job, but it sure will be fun when im done!
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