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Re: Single point injection carb replacement

Posted: Mon Oct 02, 2017 12:41 pm
by Paul H
Yes they are selling :D

Here

If you are in USA then contact me first as the shipping calc in the store is way high and VAT is deducted

Should have a turbo attachment with secondary injector and dump valve built in real soon

Re: Single point injection carb replacement

Posted: Tue Oct 03, 2017 1:53 pm
by Lanner
Thanks Paul. Does the TB have provisions for MAP sensor?
Lanner

Re: Single point injection carb replacement

Posted: Wed Oct 04, 2017 2:12 am
by Paul H
You just use the port on the OEM manifold or there is a boss on the TB you can drill/tap to 1/8th npt and use an adapter

Re: Single point injection carb replacement

Posted: Sat Nov 04, 2017 1:56 pm
by Wally
Very nice new development Paul!

Re: Single point injection carb replacement

Posted: Wed Nov 29, 2017 8:14 am
by Paul H
Wally wrote: Sat Nov 04, 2017 1:56 pm Very nice new development Paul!
Thanks
Here's a couple of pics of the plenum with extra injector and dump valve which I won't be able to supply -cheaper to make your own but you can
see how it can be done.
I had the stainless turbo headers modified so they accept the cheap "ting tong" turbos

Re: Single point injection carb replacement

Posted: Sun Dec 03, 2017 3:37 pm
by Clonebug
I take it you use the DTA ECU to run that single injector setup.

Does Megasquirt have the ability to do that????

Re: Single point injection carb replacement

Posted: Sun Dec 03, 2017 6:58 pm
by Piledriver
Clonebug wrote: Sun Dec 03, 2017 3:37 pm I take it you use the DTA ECU to run that single injector setup.

Does Megasquirt have the ability to do that????
std and extra ms 1/2/3 yes, its just a TBI setup, supported since ~dirt.
microsquirt needs high z injectors or external driver for low z.
Typically TBI injectors are lowZ, but I'm not sure what he's using...
Its possible some of the newer TBI injectors are high Z.

TBI is easy to do, but never suggested for highly tuned engines for the exact same reasons centermount carbs are never recommended: fuel fall out and uneven fuel distribution.
(basically huge AFR differences hole to hole)

Re: Single point injection carb replacement

Posted: Mon Dec 04, 2017 2:09 am
by Paul H
You can use any ECU to run that system and high z injectors upto 80lb/hr (140hp each) are readily available.I've changed down to a 60 lb/hr as maximum hp through the end castings is 100hp/5000rpm so that would be 1776/1904cc, engle 100/110, stockish heads.Anymore than this just fit ITB's but bear in mind that tuning smaller engines with heads and cams up into the 130hp and above 5000rpm is pretty pointless as the stock fan setup will rob your power almost as fast as you can make it

Re: Single point injection carb replacement

Posted: Mon Dec 04, 2017 2:36 am
by Wally
Paul H wrote: Mon Dec 04, 2017 2:09 am ...above 5000rpm is pretty pointless as the stock fan setup will rob your power almost as fast as you can make it
:lol:

As seen when engines on dyno also do a run without the belt on.
Its still pretty funny to express it like that me thinks, but Paul is notorious to tell it the way it is...

Still, my own recent development of the 2,2 turbo engine made max.hp at a real 7300 RPM. It was the higest max RPM at max hp reading at that dyno to date 8)

Re: Single point injection carb replacement

Posted: Mon Dec 04, 2017 3:31 am
by Paul H
Yes fan belt hp loss needs to measured across the whole rpm range and not just quoted as a +/- number at peak power.
If you have a 300hp turbo motor then a 25hp loss is no big deal but on a smaller NA motor then it is a substantial loss

Re: Single point injection carb replacement

Posted: Mon Dec 04, 2017 3:56 am
by Wally
Paul H wrote: Mon Dec 04, 2017 3:31 am Yes fan belt hp loss needs to measured across the whole rpm range and not just quoted as a +/- number at peak power.
If you have a 300hp turbo motor then a 25hp loss is no big deal but on a smaller NA motor then it is a substantial loss
That was my new engine, but dyno'd in N/A mode with fan belt on. It was even the horizontal (Porsche style) fan set-up with 90 degree belt arrangement ;-)
Only made 189 hp at 7300 RPM, but its low compression to be turbo'd later this year.

I agree though, fan belt loss is an absolute number per set-up and progressively higher with rising RPM.

Re: Single point injection carb replacement

Posted: Mon Dec 04, 2017 7:44 pm
by Piledriver
The Corvair racers used several tricks to counter the fan losses...

One setup added a disk under the pulley that restricted the air intake at high RPM, but had little effect at low RPM.
Second, they sprayed the belt with silicone lube so it world slip far more at high RPMs.

Yet another setup used an AC compressor clutch on the crank pulley.

Re: Single point injection carb replacement

Posted: Tue Dec 05, 2017 12:41 am
by Paul H
The VW T1 cooling was designed for 5k max which is clear as day once you do dyno tests so best to keep it there and build an engine that works best up to that limit above that use a smaller crank pulley.I think Porsche cooling is slightly more efficient but I never tested that system

Re: Single point injection carb replacement

Posted: Sun Nov 25, 2018 4:19 am
by UKLuke72
How well would this work with boost on a single injector?
Thinking stock inlet manifold, this TB and a TD04 on a 1915cc.
Fired an email off to Paul too just incase hes not lurking on the forums currently.

Re: Single point injection carb replacement

Posted: Sun Nov 25, 2018 8:05 am
by Paul H
I got the email and replied-maybe spammed

I haven't ran a turbo through it but no reason why it won't work.
Make sure you can get a single injector big enough or use a secondary injector
upstream.
Largest single high resistance injectors I use are good for max 140 hp
There is a pic on this thread of a quick mock up I did using off the shelf bits with a second injector.