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no i've been told how bad it was to consider attemtping it. had an L20B datto that would have been a prime candidate too...

so why does nearly every turbo V8 thats out there use blow through instead of draw through? we're talking serious cars, making 4 figure hp, and single digit E.T's

WTF? You're comparing a 1000+hp V8 with an L20?

What are you saying draw through are no good for?

Getting some really good horsepower out of an old carby motor, such as an L20, or building a dyno queen with 1500hp at the wheels?

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i'm saying with a draw through, all the setups run without any charge cooling, limiting total boost that can be run, and the ones that do are cops to drive because the carby is up to a couple of meteres (cooler piping length) from the actual cylinder, where normally its only a few inches. fair to say i havent driven and tested it back to back, but i know someone that has, and has explained to me in the passed just how dramatic the difference is, i have no reason to doubt him.

regardless of whether its an L20B or a 1000hp turbo V8, the characteristics of airflow dont change, and i can't see a carby working efficiently that far from the motor... would like to see, as a point of comparison, what low load driving is like in a draw through setup... something decent though, not a standard L20B with an uncooled turbo blowing straight down the intake, something with proper charge cooling and running a meaningful amount of boost.

just to clarify, i do think draw through is fine for low boost, basic setup on an old motor, something that's only ever going to see low hp levels (like an L20B), but on a grand scale, in this day in age, i think blow through has it all over draw though

Edited by VB-

I had a Mazda 323 (last of the rear drivers) with a draw through setup running 22 psi with water/meth injection. I could have pushed it harder but it would pick the left hand wheel up off the ground which made me think that perhaps enough was enough.

It had over 230hp at the bags out of a 1.4 and revved to 9400rpm. Doesn't sound to shabby to me. And I had a stock L20 (decomp plate) with a draw through T3 in a 1600. It ran a lazy 8psi (no cooling) and put out about 135rwhp. That thing was a torque monster

So I've had both, a built draw through and a stocko draw through and both were f**king brilliant and neither suffered through lack of an intercooler.

I've also had a Z18et running straight LPG and now two RB25s (R33 and a Neo Stag). I'll be damned if the draw through set ups lacked in any way.

fair call, neither 'suffered', but think about what the L20B would have been like running double that boost, for the *simple* thing of modding the carb for blow through and running a cooler?

and i'd say the 323 did have charge cooling, although its not something i'd setup in a street car through fear of me not checking it and running out lol, hence i still stand by my previous argument, although it is a good happy medium for the scenario at hand

do the 25's both really have the lpg mixer pre-turbo? any pics of the setup, sounds quite peculiar....

Edited by VB-

fair call, neither 'suffered', but think about what the L20B would have been like running double that boost, for the *simple* thing of modding the carb for blow through and running a cooler?

and i'd say the 323 did have charge cooling, although its not something i'd setup in a street car through fear of me not checking it and running out lol, hence i still stand by my previous argument, although it is a good happy medium for the scenario at hand

do the 25's both really have the lpg mixer pre-turbo? any pics of the setup, sounds quite peculiar....

The L20 could have taken much more boost with a little more work. It was a tired old motor so 8psi was an amount which wouldn't stress it too much.

The Z18 had the mixer pre-turbo, the RBs weren't LPG.

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