Author Topic: V8 intake manifold - are D & K Jet the same?  (Read 2449 times)

13B

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V8 intake manifold - are D & K Jet the same?
« on: 09 October 2007, 04:02 AM »
This is more for the mechanically minded enthusiasts, but is the manifold the same on the D Jet as the K jet? 

I'm not talking about the connections on top (they are obviously different) but underneath and the way it fastens to the engine block, are they the same or different.

Anyone got a spare damaged one floating around they want to fling my way?  I want to look at what I have to do to customise it and add an adaptor plate for a square-bore Holley 4 barrel, the idea being to fit a Holley Pro-Jection system in place of the D or K on a future Team116 car.

Ian.
450SEL 6.9 #5440 = V MB 690 , 450SE # 43094 = 02010 H , 190E/turbo # 31548 = AOH 68K

Big_Richard

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #1 on: 09 October 2007, 06:36 AM »
upper and lower intake manifolds are totally diffferent D & K jet version v8's

That i know because i have the EPC

I do beleive that the whole assembly, upper and lower can be interchanged though, as its been done before when converting a K jet 450 to modern EFI..


SELfor50

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #2 on: 09 October 2007, 07:31 PM »
So if you interchange a K-Jet manifold (upper AND lower?? excuse the ignorance, i don't know too much bout these things) with a D-Jet manifold, is it then easier to convert to EFI??  or would you simply get a custom manifold made??

Also Ian, the holley you wanna put on - that's a carby right??  Will that pump the horsies to the wheels?
"Man who come first, wins race." -Unknown

-= 1978 - 450 SEL [Euro] =-  Locked
-= 1976 - 450 SE 6.9 #2 =-  New Heart

13B

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #3 on: 09 October 2007, 08:33 PM »
Both Manifolds have 8 injector ports, so if you wanted to put multi-port EFI (ie. normal aftermarket EFI like microtech or motech) I can't see why either system would be harder than the other.  Unless I'm really mistaken, just jettison all the old D or K jet stuff, stick 8 injectors in, plumb in an XF throttle body, fab a fuel distribution rail and wire up an ECU.  Theres other little things to do like put a lambda sensor in the engine pipe etc. but thats basically it.

With a squarebore adaptor I can put a carb or on Holley pro-jection system (since both use the same mounting flange).  If my racer turned out to be a 450, then I'd put a Holley 600, or in a 350 then I'd use a Holley 465.   The projection flows 750cfm but thats not really a problem since the fuel injection partly makes up for the over carburation the projection is likely to generate.

For testing purposes however I'd put the old reliable 600 carb on to get it up and running.  A carb on a V8 MB would improve power when optimally set up, but would use more petrol, emissions would go thru the roof, fuel slosh may be a problem until Holley race float bowls were fitted, but apart from that it should work.  Since I have these holleys on hand it makes sense to try them out.

I'm figuring when i find and buy this beast the D or K jet will need work / hardly work so rather than spend $ fixing the D or K, just go the H(olley).

I.

450SEL 6.9 #5440 = V MB 690 , 450SE # 43094 = 02010 H , 190E/turbo # 31548 = AOH 68K

Big_Richard

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #4 on: 10 October 2007, 03:16 AM »
So if you interchange a K-Jet manifold (upper AND lower?? excuse the ignorance, i don't know too much bout these things) with a D-Jet manifold, is it then easier to convert to EFI??  or would you simply get a custom manifold made??

Also Ian, the holley you wanna put on - that's a carby right??  Will that pump the horsies to the wheels?

I have an article on my computer somewhere showing the procedure that was undertaken to convert a K jet 450 to use a GMH 5 litre engine management system. It included swapping over the intake assembly to the earlier D jet version, wiring up all the mongrel componentry and tuning it on a dyno.

In short, it produced a *shit* load more power @ less fuel consumption.

OldMercs3

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #5 on: 10 October 2007, 01:01 PM »
D-jet or K-jet the injector ports are in the cylinder heads, and these differ too.  As I understand it a D-jet car will easily accept EFI injectors (per it's design) while the K-jet cars utilize nozzles and any attempt to convert to EFI will require some adapting.

zeppelinboy

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #6 on: 10 October 2007, 01:21 PM »
This guy:
http://hitechengineering.net/dnn/MegaSquirted450slc/tabid/54/Default.aspx

Says that Ford mustang injectors come fairly close to fitting into k-jet heads (they fit with a slight modification to the injectors) and says that others have reported them fitting without any modifications at all.

Justin
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96 Chevy S-10 w/LT1 inside

SELfor50

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #7 on: 10 October 2007, 05:31 PM »
So if you interchange a K-Jet manifold (upper AND lower?? excuse the ignorance, i don't know too much bout these things) with a D-Jet manifold, is it then easier to convert to EFI??  or would you simply get a custom manifold made??

Also Ian, the holley you wanna put on - that's a carby right??  Will that pump the horsies to the wheels?

I have an article on my computer somewhere showing the procedure that was undertaken to convert a K jet 450 to use a GMH 5 litre engine management system. It included swapping over the intake assembly to the earlier D jet version, wiring up all the mongrel componentry and tuning it on a dyno.

In short, it produced a *shit* load more power @ less fuel consumption.


Thanks PB, i've had the same article sitting here for quite sometime - and i'm dying to convert this puppy to EFI.
I really wanna just take it somewhere and pay them to do it....but i'd rather wait till Mercules get's a chance and that way I can pay him to do a job that I'm pretty confident will be much better! ;)

If anyone wants me to post this article up, i've got it ready to go.
It's pretty detailed.
"Man who come first, wins race." -Unknown

-= 1978 - 450 SEL [Euro] =-  Locked
-= 1976 - 450 SE 6.9 #2 =-  New Heart

450SLC 5.6 supercharged

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Re: V8 intake manifold - are D & K Jet the same?
« Reply #8 on: 30 October 2007, 04:45 PM »
H i  here is the thing about EFI eather K-jet  ore D-jet  there is one issue if you got an early D-jet from say 73 its harder to use newer injectors body  in to the  smaller wholes where to mount injectors in  its a big different betwen early D-jet engine to say a year later ore more 74-75 is perfect the wholes is much wider and the new injector type is fitting right in . same to the K-jet  just remove the plastic **adaptor** sitting there and bam ure in the ballpark just plug and play   so in short  there is no diff in most case when we talk about mount injectors in to D-jet ore K-jet  just check out for the older ones  other way just rock . there is one thing for sure about these engines they just screaming for a new EFI and remove the distributor  and just D I S  that's the best way to success .
« Last Edit: 30 October 2007, 07:01 PM by 450SLC 5.6 supercharged »
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