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Which Works Better For A Small-Block Chevy, The Carburetor Or The TPI System?

Which Works Better For A Small-Block Chevy, The Carburetor Or The TPI System?

You can spot it a mile away, the TPI setup. One square brick with a throttle body at the end, with long runners leading down into the manifold base. If you were into late-model power in the 1980s and 1990s, this scene was familiar to you. Camaro, Corvette, Impala, whatever…the L98 was a torque-heavy small-block Chevy that gave GM fans hope that the power was coming back. It did…the C4 Corvette managed to get banned from SCCA Showroom Stock and from 1987-92, the F-bodies made good use of the engine as well…even if GM was still culling power figures to protect the plastic fantastic.

Richard Holdener will test an engine to death for the data and won’t leave any stone unturned, so it’s time to pit the TPI setup against your typical dual-plane intake and four-barrel setup. And just in case that isn’t enough, let’s go ahead and add in a few more tests, including camshaft swaps, to see not only where you can get your power to, but where on the curve you can put your peaks at. Think about it…that pretty clean IROC-Z was alright back in the day and is appreciating by the week. Imagine it looking dead-nuts stock and rocking like it never did before. Just putting that out there…

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9 thoughts on “Which Works Better For A Small-Block Chevy, The Carburetor Or The TPI System?

  1. Ernesto Olivas

    I have a 96 buick roadmaster and would like to get it back to to bad ass mode its a 5.7 and runs great but its has the opti spark on it imstead of a old fashinfed carb. I dont have alot of money or any money for that matter but would like to see if anyone can help me out

    1. Ken

      Lt1 is far and away your best bet. Optis get a bad rap. My 95 Buick had 150,000 on the stock opti

    1. David Grant

      Long or short, Headers are to compliment & tune your other components. This, as are everything else, a very misunderstood subject. I know many many people will claim that sticking long tube headers on their relatively stock engine made big Power, when in fact this is not always the case. There are many other factors in deciding which headers to use, such as camshaft specs, intake manifold specs, cylinder head specs, etc etc. And since I do not have all of those I cannot just say what to use as most will. Another factor is where do you want to make your power? What type of Power Band are you looking for? These are important factors because there are too many who are using some parts which will complement higher RPM horsepower and then using other parts which will complement lower RPM torque. Then they will have a mismatch of Parts which contradict each other.
      In general sometimes so call the restrictions can actually help low-end torque and this is due to these specific Parts helping velocity, tuning, and creating a scavenger effect. Obviously there is a lot more to this, & is not so cut & dry. Just sticking super high flowing cylinder heads & headers may not make the power you want, or where you want. In general hi flow large CFM parts help make top-end higher RPM horsepower. So using these parts may get you that Peak horsepower but it may also be in a range in which your engine will rarely be in, or completely out of it’s RPM range. This especially becomes an issue when you have done nothing to build up the bottom and middle-range of this Power Band. Being that an engine is essentially an air pump, the object is getting a certain amount of air into the engine at a specific point in time, which is measured by RPM. This is where both dynamic and static compression ratio, a turbo, supercharger or nitrous, cam timing and valve events, cylinder head specs CFM, valve size, etc) , intake specs, and specific exhaust systems (type of header, lengths, diameters,etc) play a big role. Because all of these can be manipulated in such ways to get the best results in a desired Power Band. So the first thing I would tell somebody is what type of engine do you want to build, do you want a street machine or do you want an all-out race car? Because you really can’t have both. There is always a trade-off in which direction you want to go.
      Another big issue is people getting advice from other people who are building cars in a completely different direction from which a specific car is intended to be built as. If you’re planning on building a street torker but you’re getting advice from somebody who’s building and all out top fuel car or something similar, then this is probably not going to be the best advice to go on and or to duplicate.

      In general large diameter, long tube headers will not benefit a stocker or relatively stock engine. It is & has to be a complete package, & matching of components, & to do this in your chosen power band. So unless everything else is upgraded accordingly, you may actually hurt power in where you want it. I mean of course you will have picked up a few points of hp all the way up at the top, but unless your pedel is buried & maxing out top end RPM, you won’t feel it.
      Typically you will feel more power, and get a torque and some HP increase with a set of shorties on a relatively stock SBC or SBF. Something that will be noticed in a street machine. Again there are many other variables to factor in, but as a basic best advice on what little i know. Also basing this by the question itself. If I had more info, i could guide you in a better direction. And mot to toot my own horn, but my brother & l have been doing this for many many years, & are appalled by how much bad bad bad information is out there, even from so-called professionals. I think they just group a few basic variables weather on the person or type of build and then just go with some basic facts that kind of work. Unfortunately there is no cookie-cutter one fits all in engine building, the intended use of the engine, type of vehicle it’s being used in, and last but not least the person in which is to use all of this.
      Kind of like after everybody so fast and the furious and never drove anything faster than their mothers Honda with an automatic transmission but decided they wanted 500 plus horsepower cars and to drive stick shift, and then were perplexed how they ended up into walls and or bad car accidents. Well this same thing applies across the board, as in how many people truly have driven a car with 400 + horsepower? And they hear all these big numbers being thrown around and so they want 700, 800, and or 1000 + horsepower, but have no clue on what that type of power is like.

  2. Dennis chambers

    Iv got a 1995 Chevy Silverado. That wonts to over heat.and I’m st a lose what is the problem. Can you give me a idea why.it is a 350 motor.

  3. Robert g Demgard jr

    well.i pulled a 53chevy panel truck out of the woods in vermont.three trailor loads.yes it was bad.but I can’t leave it.ten years later.on a 86 Chevy pickup chassis.narrowed.shortened.finally set body on.still had plywood rear floor.well long story short.it became a daily driver with built motor.four speed Saginaw trans.posi rear.my 8yr old grandson is now the proud owner.hes a motor head.bless his heart wish I could send pictures.its one of a kind..87 celeb steering.s10 brake booster and master.its the short body..I’m a disabled veteran.and made it a rolling memorial to all veterans.i now live in tennessee.it has been called icon.. proud to drive it.and many many hours and mistakes but I built it myself.my grandson has put videos of it on Facebook.many replies..been offered good money for it.but I’d rather it gets passed down in family.im now 66yrs old.a very proud american.my grandson will surely take care of Pa PA’s toy handed to him. got 327 boreded 040.plenty power and many trips back n forth to vermont.tired iron still lives.named “trouble” well earned.

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