Sign in to follow this  
holdenman

ITB's for Holden 6

Recommended Posts

I am trying to decide on the future induction of my 3.3 Holden engine that runs about 11.5:1 compression with big Ports, Valves and camshaft to match will willingly rev past 7000rpm

I tried a 2-barrel then a 500cfm Edelbrock but felt it was a bit down on power so I threw on a 750cfm Holley and it showed huge power gains and that the engine needed more CFM

This is where some of you are brilliant in helping the likes of me that only knows about 3.5PSI injection not 60PSI. I can get 45mm ITB's and using velocity stacks but if I understand correctly then I need a basic ECU to run partly off a balance tube,  TPS and o2 sensor then a guru to tune it

Spark can be run separately or integrated as I run HEI dizzy and 

Who what how are the questions

 

Share this post


Link to post
Share on other sites

efi works well on the old 202, mines turboed running a link atom have a look at my  vk build thread,  iv used a 36-1 crank trigger on the balancer, deleted the dizzy and using an  AU falcon coil pack wasted spark  setup, pair firing the injectors, injectors and fuel rail is easy  if the throttles have injector bosses, just need an efi pump and fuel reg to  feed it. would need sensors for coolant temp air temp and TPS, can use a MAP sensor if you can plumb all the throttles to a small  manifold, usually  ends up using the TPS as the load value rather than map  due to  cylinder fluctuation and lack of a plenum 

  • Like 2
  • Thanks 1

Share this post


Link to post
Share on other sites

My brother in law has a VK with a fairly warm 3.3 12 port with a cut n shut GTR Torana manifold on it. He has been assembling parts for a 235 stroker running efi turbo. 

 

 

But an LS has taken care of that. Cheaper, more power. 

Share this post


Link to post
Share on other sites

So you'll need to buy an ECU and a wideband oxygen sensor, I'd reccomend getting a Link Fury ECU as it's designed for 6 cyl engine and has a wideband controller built in.
So it makes wiring easier and cheaper.

The tricky bits about an older engine for EFI are that you need a crank and cam angle sensor retrofitted. 

As well as injectors of course.

If you want to do things cheaply you could buy an ECU that only has 4 injector and ignition drives, and put them in pairs. But if you've got inlet reversion issues with big cams and high comp, its nice to be able to adjust the injector timing so that each cylinder is the same. So you can avoid spraying when it's spitting it back out.

Having individual coilpacks is super awesome. 
This way you can have knock control working per cylinder, or have a traction control setup that shuts of cylinders until your wheel slip stops beyond a certain point. 
Which is helpful if you have a car that's boggy off the line but then wheelspins badly too if you launch too high in rev range.

Depends how far down the rabbit hole you want to go! But I reckon once you have a decent EFI setup you'll be amazed at how it's able to squeeze the most out of your engines powerband and also have great economy and drivability, cold starts etc.

I'd not reccomend buying an obscure ECU that not many people know about, as sometimes it can be hard to get people to tune it. 
Link and Haltech are popular options, but Haltech is more expensive and leaves a few things missing which are big annoyances.

 

  • Like 1

Share this post


Link to post
Share on other sites

Thanks for the good stuff Roman, you have given me more to think about

The old Jetronic injection on the black motors gave a squirt per revolution and used a crank pickup but then the std EFI manifold is too restricted to get maximum performance as the terrible casting caused restriction and was totally uneven. Falcon injectors used to be the go for them.

I ran VK Injection on my LC and got about the maximum I could from that setup but then went to DCOEs and picked up another 60+HP and way more torque.

Until I source everything I am going to run triple webers and maybe progress to EFI later which I may combine it with a turbo. I also need to do some other bits to the car like a LSD and better brakes before I take it to the track.

  • Like 2

Share this post


Link to post
Share on other sites

Also if you are ever buying injectors, make sure they come with a CC rating and deadtime information. 

Some injector companies even decent ones are shocking for not supplying data, and then they run like shit. 

 

Share this post


Link to post
Share on other sites

I reckon I could get all the bits needed apart from an ecu and it would include a wideband 02, TPS and Ignition system for around NZ$2700. The fuel system can be fairly simple, I have a couple pumps and 1 adjustable regulator so mainly hose and fittings.

I decided to park this for now as I will get the new triple webers up and running first and I also need to build a new exhaust system 

 

 

Share this post


Link to post
Share on other sites

If you decide to go the ITB route, talk to @BobbyBreeze at Whitleytune. He casts inlets and throttle bodies and can help with getting the right lengths for harmonic wave tuning. 

  • Like 2

Share this post


Link to post
Share on other sites

Thanks Truenotch, Harmonics can be very powerful alright but never though of it in the induction system.

The Holden 6 doesn't like hanging around 6000rpm because of this reason and I either change just under or quickly go past it, the current engine I would estimate would rev similar to my old one at around 7500rpm but I pucker more as the revs climb and so far only revved to around 6600. The DCOEs will help more than the current 4-barrel.

Share this post


Link to post
Share on other sites

If you want gross but effective triumph 2500pi mechanical injection works on the old 202 use efi throttle bodies as the trumpy ones neck down to about 32mm and are worth big bucks but the mechanical injection just mounts off the dizzy so pretty user friendly to modify.

Old tech as fuck once you get your head around the gear its not bad and will make good power.

Pair it with clever ignition would be a very good thing. 

I ran lucas mechanical injection off a 2.5 on a 2 litre triumph race engine i scored that was running triple webbers i couldn't afford them so was worth a punt, it was a punchy weapon! Once it was setup it just worked. 

 

 

images - 2020-10-31T224724.684.jpeg

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this