EFI or Blowthrough?

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70wayfarer

70wayfarer

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ok guys whats the consensus on efi vs bt. i'm bt at the mo. is efi easier to tune. thinking bout making the change, but need convincing its for the better.
what size injectors would be needed, what controller, link, megasquirt ?
have 2 x walbro 392 pumps 1/2" feed, 1/2" return.
got water/meth set up.
this is street/strip.

oh yeah its a 410 sb, s475 turbo.
cheers
 
EFI is a vast improvement over carb any day. It will be more consistent and reliable. You have cars pumping out a 1000 hp and are daily drivers.
 
Both have their benefits, there are carbs on blow through pushing over 2000hp, fuel injection you can more fine tune per say but with fuel injection carb have also come a long way, I'd call or write a few company of both a see what they say, for carbs pro systems, c&s. Injection can write mega squirt. The 392 w albros are good pump I prefer bosch 044, found a site that sells cheaper but authentic, I bought two for my twin turbo dart on injection.
 
Matts440 said:
Both have their benefits, there are carbs on blow through pushing over 2000hp, fuel injection you can more fine tune per say but with fuel injection carb have also come a long way, I'd call or write a few company of both a see what they say, for carbs pro systems, c&s. Injection can write mega squirt. The 392 w albros are good pump I prefer bosch 044, found a site that sells cheaper but authentic, I bought two for my twin turbo dart on injection.
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had bosch pumps. too noisy, so changed to the walbro. much better.
changing to efi will mean investing more $$$. can recoup some of cost selling my bt carb and 6530 though. my carb is a prosystems.
 
Oh okay. Yea they can be noisy but I bought a mount with isolators on it to keep the noise down. Efi is nice dont get me wrong can fine tune the crap out of the system. My next build for my 72 plymouth will be twin turbo and blow through carb hopefully by then pro systems with have their sv1 blow through carb made, but it's a long ways off might change who knows. I think Louis that made the twin set up for my dart got some 160 lbs injectors can look back on the thread, but it will handle 1000hp if thats your goal.
 
the guys with efi will obviously say that it's the way to go and vies versa for blowthrough I suppose.
mine is a prosystems bt carb. it was on my 360 with vortech v2 supercharger. when I decided to go turbo I contacted Patrick via his forum and asked what changes would the carb need. his reply was that it would need little if any change and it would adapt itself nicely. couldn't work that out as we went to 85 jet primary from a 68 and 107 rear from 86. the rear has no pv also and I think it should. i'm no expert but from what I have read on various turbo forums bt carbs have pv's front and rear.
would prefer to stay with the bt cause i'm getting the hang of it now.
 
most people dont run the rear power valve. those are some pretty big jumps in the jets. like the dude said it shouldnt have needed much going from one engine to the other. what is your cruise afr? what power valve setup are you running? are you sure its working?

im running a blowthrough. i like it. if i had the money i would probably go with one of the easy efi setups. the self learning ones. a couple of them are setup to handle boosted applications. i think the max is only 2 bar though.
 
RustyPlymouth said:
most people dont run the rear power valve. those are some pretty big jumps in the jets. like the dude said it shouldnt have needed much going from one engine to the other. what is your cruise afr? what power valve setup are you running? are you sure its working?

im running a blowthrough. i like it. if i had the money i would probably go with one of the easy efi setups. the self learning ones. a couple of them are setup to handle boosted applications. i think the max is only 2 bar though.
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those were the changes needed to get afrs good from idle 14 to cruise 12.8 to 11.5 wot.
carb as it came off the 360 v2 to the 410 s475 was lean all the way getting to 17-19 under boost 16 ish at cruise and pig rich at idle.
got it sorted on the dyno. was leaning slightly on power pulls from 0-4 psi but then came good. no brpv. 17psi 640 rwhp I was excited.
anyway next session a week later the water meth failed at wot and melted a piston.
 
might wanna look into a boost referenced power valve. idle afr is gonna be what ever the motor wants, there is no right or wrong number there. you could lean out the cruise more. wot looks good.
 
Brian at Imm said to check out CSU carbs for blow through and that a tuned carb would run just as well. Problem then is someone that can tune carbs and boost
 
Fst73_410 said:
Brian at Imm said to check out CSU carbs for blow through and that a tuned carb would run just as well. Problem then is someone that can tune carbs and boost
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exactly, finding someone that can tune. that was my issue. happy with my carb and getting the hang of that and the 6530.
referencing the pv there seems to be no right or wrong, it's whatever works, or can you buy these now.
 
I think efi is good if you get a good system. Bigs3 or megasquirt, will help in long run if serious but if not ultra competitive, I would think carb is great
 
i drilled the main body into the pv cavity and use turbine back pressure to open up the pv. works like a charm. so much so that i went from a lean condition to rich without changing anything but the reference i used.
 
I am a fan of EFI, so much adjust-ability. The kind of power you are making, it would be nice to have more control. You may need to dial in boost for traction, run the meth injection, tune with a flex fuel sensor for a variety of fuels. So many options, and the tuners are getting really good.
 
QuickFuel makes a blow through capable throttle body injection system that may be what you are looking for. Quick fuel QFI, I'm thinking about running it on my naturally aspirated 318.
 
RustyPlymouth said:
i drilled the main body into the pv cavity and use turbine back pressure to open up the pv. works like a charm. so much so that i went from a lean condition to rich without changing anything but the reference i used.
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I did a similar thing but used the channel used for vac advance and extended it to behind the pv. blocked the hole in body that goes down to throttle plate. took signal from turbo housing. when I went to the dyno he said the signal should come from the manifold.:banghead: basically part of what the crutch mod consists of. what I did is what the dyno guy said to do. it seemed to work after a lot of f#@king around. the dyno guy was a **** useless tuner.
despite him telling me otherwise when I booked the session it soon became obvious that he didn't have a clue tuning a turbo V8.
once my rebuild is done car will go on trailer and head north four hours drive to a reputable tuner.

on the brpv thing, what really does work. seen so many different methods on the net.

no I am not super competitive. I just love to race and have fun doing it. winning is a bonus though.
 
RustyPlymouth said:
http://slantsix.org/forum/viewtopic.php?t=54407&postdays=0&postorder=asc&start=225
that brpv works like a champ ive tried a few of them. this one definitely works and works well. the other ones wouldnt open all the time or would leak or wouldnt open all the way. this one opens all the way every time.
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this is why i'm thinking efi now. spent the money on a built carb for forced induction and now I have to add bits and drill holes. might as well sell my carb and msd 6530 and go efi.
 
Fst73_410 said:
I think efi is good if you get a good system. Bigs3 or megasquirt, will help in long run if serious but if not ultra competitive, I would think carb is great
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so how does the megasquirt rate compared to others. what is Bigs3.
a member here is using the fast xfi 2.0 with good results. pricey though.
 
70wayfarer said:
so how does the megasquirt rate compared to others. what is Bigs3.
a member here is using the fast xfi 2.0 with good results. pricey though.
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The same engineer who designed the original DFI also designed FAST and now Bigstuff3. I don't think you can go wrong with any of them, even the new haltech stuff is pretty nice.

I went with FAST XFI because of it's popularity, and all the tuners around me know how to use it. Fast also offers a lot of high quality parts and addons. I am using their Edash, pressure sensors, and boost control solenoid.

If you decide on FAST, I think I remember enough about the install to be a resource, I can also send you my tune, it might make a decent base tune.
 
MrMoparMan said:
The same engineer who designed the original DFI also designed FAST and now Bigstuff3. I don't think you can go wrong with any of them, even the new haltech stuff is pretty nice.

I went with FAST XFI because of it's popularity, and all the tuners around me know how to use it. Fast also offers a lot of high quality parts and addons. I am using their Edash, pressure sensors, and boost control solenoid.

If you decide on FAST, I think I remember enough about the install to be a resource, I can also send you my tune, it might make a decent base tune.
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apart from the xfi 2.0 what else is needed to complete the change over to efi.

ps love your build man.
 
70wayfarer said:
apart from the xfi 2.0 what else is needed to complete the change over to efi.

ps love your build man.
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There is some added expense beyond the kit, you can save a lot of money buy doing some of it yourself vs buying parts.

You will need all the sensors, you can get them from a parts store (pretty common GM or Ford Sensors), or buy the FAST sensor kit. You need a Coolant Temp Sensor, Air Temp Sensor, MAP Sensor (You will need at least a 3 Bar for the boost you were running), and Throttle Position Sensor. You can go either way on the Idle Air Control motor.

You can either buy an efi intake manifold or build one out of yours. I used a Mopar M1, drilled and welded in bungs. Bought some fuel rail stock, drilled, tapped etc. Also need to drill and tap a the water jacket for the Coolant temp sensor. MAP sensor will be on the manifold side of the butterflies, Air temp just before throttle body, and Throttle Position on throttle body shaft. Idle Air is usually on the throttle body as well.

Injectors, I used 800 CC high impedance, sized for E85.

Fuel pump will have to make at least 45 psi, with a regulated return. Lots of options here, an inline A1000, intake pump, surge tank, multiple pumps, etc...

A throttle body, mine is a 4150 mount like a carb, but I think a modern large bore single butterfly would be great for a turbo car.

Last is the timing: You can buy a dual sensor distributor with phase-able rotor from FAST which seems like a nice unit. Some guys use a crank trigger, I just used a Mopar magnetic pickup distributor. This is just a cam sensor to trigger the computer. You have to eliminate the vacuum and mechanical advance. I removed the vacuum can and welded the weights. The timing needs to be set about 50 degrees advanced with the rotor phased at about 20-25 degrees. I was able to use the vacuum advance to phase the rotor position and locked it down with a screw.

If you can swing the investment, it is a fun journey.
 
ok then, this is the most popular ecu in NZ. most tuners are conversant with these. all accessories available here. 3 options the one below I think will do the trick.


http://www.linkecu.com/products/engine-management-ecus/g4plus-storm

I can mod my intake. have dual walbro 392 pumps with Mallory boost referenced reg, have 3 bar map, msd pro billet dissy.
looks like I only really need fuel rails and injectors, throttle body.
other sensors I can get also.
what about coils?

this might be more affordable than I thought. definitely food for thought. can recoup part cost from sale of my carb and 6530.



cheers
 
Sounds like you are well under way, I like that ecu. You can just use a standard coil like the MSD blaster. It is possible to go sequential with coil packs but it is not necessary.
 
what are the megasquirt systems like compared to the others. I see them used quite a bit.
 
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