Billit injector blocks
 

Putting out a feeler to find some billet injector blocks for the "Old Sled".
I need standard 930 32mm. Thought some the EFI guys might be of some help.

THANKS !!!!!
Cole

Try www.goingsuperfast.com

Try Chris Carroll at TurboKraft in Arizona.

2nd on TurboKraft
http://forums.pelicanparts.com/uploa...1233451038.jpg

Great idea - with the insulators (a must) you have one hell of a setup.

Thanks for the suggestions. I have heard a lot about Turbocraft but have never
bought from them.
Would anyone happen to have a set of billet blocks they have replaced when converting to EFI
before I go buy new?
Those Turbocraft blocks are pure art.

THANKS AGAIN !!!!!!
Cole

The problem with used injector blocks is they are plastic, phenolic, & may end up cracking on you. Correct me if I am wrong, but the heat from our motors can cause the phenolic blocks to become ridgid, which can crack, hence leaks may occur. Something to think of when going used.

How much does a set of billet injector blocks costs for grins?

more than i would pay...
 

CIS Injector Blocks
$495.00

http://www.ultimateaircooled.com/holder01.jpg

And the thread link...............

http://www.shoptalkforums.com/viewtopic.php?t=123329

For the price of new oem ones, I dont see why anyone would want to go used. If you own a 930, cheaping out shouldnt be an option. Those billet ones sure are nice!

Daily Driven 88,

I am not cheaping out here. My original phenolic blocks are presently crack
free. I was not looking for used phenolic blocks, I was looking for used billet
blocks. When most users convert to EFI they change intakes and use fuel rails.
I simply thought, by chance, one of those users might have had billet blocks
with his original set up that they would be willing to sell.
I am not cheap. I simply have a limited amount I can spend. In the past 3
years I've had a Heart Bypass and then got Cancer that required 7 additional
operations. I just finished Chemo that consisted of three treatments a month
for 6 months at $14,000.00 a treatment. It presently isn't prudent to take
money from the household to buy parts for "The Old Sled". Consequently I sell the
parts I'm replacing to fund the new ones and that requires me to shop before
I buy.

Cole

My comment was not directed to you. It was a response to the comment I quoted in regards to used phenolic blocks.

Those injector holders are the $hit!!! I can see so many new applications for such a product.

Thanks for the link. I will be waiting...

Turbokraft
 

I also have Chris's blocks from Turbokraft. They worked great and I am very happy.

Thanks,
Bryan

Do you ever get any hot start roughness/sputtering caused by heat transfer from the heads into the metal injector blocks causing fuel vaporization in the injectors and lines shortly after a hot shutdown?

Seems that would or could be the only summertime drivability problem with metal injector blocks, and thats why the factory used phenolic resin or bakelite for them... to insulate the injectors from cylinder head heat.

I just wish they made them with thicker walls so they can be hogged out to 38mm without making the walls so thin they crack and crumble when tightening down the intake manifold nuts

Thoughts
 

JFairman,

I think the fact that the billet blocks come with the phenolic spacers answers your question of heat transfer and why they were designed that way. The benefit is what you mentioned regarding "going bigger" and Chris at Turbokraft told me they have never had any issues with heat.

I was curious about the same thing when I was looking for a solution to my stock spacers.

Bryan

cool, thanks for the info.

The old BMW 2000CS, 2002ti, and Mercedes 190SL came with Solex 40PHH dual sidedraft carbs and similar phenolic spacers between the carbs and short manifolds for the same reason... to try and stop heat transfer fuel vaporization.
They would still vaporize and boil gas over from the float bowls into the primary venturis after a hot shut down though.
Weber DCOE carbs aren't quite as bad about doing that.

I was worried about the heat transfer as well. I wasn't sure if the injector itself not being isolated and directly attached to such a big piece of aluminum heat sink would have caused problems.

I ended up boring mine out to 31.5 mm (if I remember correctly)

I think after all the good reviews and not seeing any evidence of the heat soak problem I may have to buy a set when the time comes around.http://forums.pelicanparts.com/uploa...1233637641.jpg

The Blocks that are pictured are 38mm. I bought them for use with SC heads.

about this Blocks,

does any of you make your original ones bigger, they are 32mm inside and 41,5mm outside

i like to bore out mine, how big could i go do you guys think,
i guess every one that have ported heads have bored out blocks?
but it seams to big to bore out to 38mm in the blocks as it is 41,5 out side
there for i thinking not to go with 38 inlets in heads, maybe 36 would go?

what is you experience?

ok, i was wrong I didn't bore mine out to 31.5mm by memory.


I actually ended up boring mine out to 37.5mm. I just measured an extra one I did this morning.

Hope this helps.

is hard to see, was this the factory bakelite ones?

Nice. The bravest I got was to 36mm. Mine measured OD 40.5, so I'm at 2.25mm wall. At 37.5mm that's 1.5mm wall thickness. Are you running 1bar of boost through them? How long have they been back in? Did you use new ones? I bought a new one to do test cutting on, and then when I cut my old ones they were NOT in great condition. If I were planning to run my CIS for much longer I'd order 5 more new ones to mod.

Phenolic block walls are pretty thin as is - the aluminum blocks with some manifold work + SC heads are a great idea.

I have yet to do a thing to my phenolic blocks or manifold.......

Thought you'd like those :)

Yes, they are the genuine bakelite injector blocks from Porsche.

They were brand new from Porsche and machined really well with an amazing surface finish.

I have only run .8 bar through them controlled via a Tial 46mm waste gate.

They have been on the car for about a year or so.

There was an interesting observation I made when I removed and inspected the old ones that were also bored out. I found that the ones that had cracked were cracked at the bottom flange area of the block. The thin area of the walls were all intact.

It's my understanding that the stock ones crack in this area also. I am not really sure how much of the life I have "bored" out of them. Only time will tell.

-Adam

I'm running the OEM injector blocks bored to 38mm with 1 bar boost and k27 turbo. After 7 years i'm looking to replace at least 3 of them due to cracking of the thin sidewalls. The next set I'm going to bore to 37mm. Hopefully they will last longer.

If the exhaust is 34mm it would seem something in the 34-36mm would be a fit looking at what Porsche did on there NA motors.

How do we come up with an ideal intake or exhaust port size?

I am guessing we do not want to go any larger than needed to try to keep intake port velocity up which seems to be relevant with CIS looking at what Porsche did with the SC reducing its intake port size half way through production.

As a point of reference I have one friend that made 425+ rwhp through stock intake ports and SC cams. He did however have an extrude honed intake manifold with tapered injector blocks down to the stock ports.

I wonder if we can use the relative difference between intake and exhaust valve sizes and a valid point of reference.

The exhaust valves are 41.5mm diameter and or intake valves are 49mm. Thus, the intake valve has an 18% larger curtain area under its valve seat.

It would seem we would want an 18% larger intake port cross section to support the 18% larger area under the intake valve seat.

A 34mm exhaust port has 1.42 sq inch volume. If we want the intake to have 18% larger cross section it would need to be 1.68 sq inch. A 37mm intake port has an 18% larger cross section than the 34mm exhaust port.

However, the intake valve is also open longer than the exhaust with most cams so 37mm might be larger than needed.

Thus, it might be that unless the exhaust ports are opened further anything larger than 37mm for the intake is probably not going to be much of a benefit.

Of course there are more variables than this.

I think if I was doing a motor today I would look at something in the 34-36mm range with the right cam.

I have the set pictured for sale, they have been opened up for the large port SC heads.