New tube exhaust and intake manifold

[jcsb]

This is just part of the complete rebuild I'm doing on my 1960 3000 Mk1 BN7. While I'm doing all the mechanical, the body will be done by someone else. I should mention that the engine and trans will be coming out to do a total rebuild and smitty conversion. I took the original manifolds, carbs, etc. off to test fit prior to pulling the engine. Remove the manifolds while in the car was fun (not).

John

 

[Chris_Masucci]

Beautiful! I've been looking at that intake for a while but decided to at least finish the car first. I do have those headers though. I had them coated and I wrapped them as well to cut down on cabin heat.

 

[jcsb]

Beautiful! I've been looking at that intake for a while but decided to at least finish the car first. I do have those headers though. I had them coated and I wrapped them as well to cut down on cabin heat.

Chris,
Thanks. I'm planning on wrapping mine too! They are stainless steel. I'm rebuilding a SU HD8 for the intakes. To type everything I'm doing would give me writers fatigue. Looking forward to sending the car off to get the body massaged and painted (above my pay scale).
John

 

[HealeyPassion]

That appears to be a DMD intake manifold, but I don't recognize the tube exhaust manifold. Is it custom? Steve

 

[jcsb]

That appears to be a DMD intake manifold, but I don't recognize the tube exhaust manifold. Is it custom? Steve

No it's not the DMD. I tried for 3 months to get one, but was unable to get a reply from them. I got it from AHspares as I did the headers. With these you don't have to use vertical floats.
John

 

[drambuie]

Just curious, what is the horse power increase they are claiming with this set up? Are you flowing the head? Are you going to run a side exhaust from Welsh? Or a custom fitted out the rear of the car? Doing any high performance motor mods?

 

[jcsb]

Once I get the motor out and see what condition it's in I will decide at that point how far I'm going. I will change the cam out to something hotter and some other work. At one point I had about $9k worth of mods picked out, but have decided to review what will give me the biggest bang for the buck. I noted earlier that I'm changing out the SU's to the 2" HD8's. Some mods make small gains at a big price and since in the end this will be a street car I'm going to want it to be everyday driveable.
John

 

[steveg]

John,
Your "neighbor" Jim Hockert has an excellent paper on prioritizing hopups:
https://www.ntahc.org/techtips/CompEngine1.html

 

[jcsb]

John,
Your "neighbor" Jim Hockert has an excellent paper on prioritizing hopups:
https://www.ntahc.org/techtips/CompEngine1.html

Yep I read that a while back. Since this isn't my first build I can say from experience that you need to determine what your goal is. I will probably go with Denis Welch aluminum heads (fast road), cam, and new forged pistons. Considering what else I've done this makes the most since.
John

 

[steveg]

Yep I read that a while back. Since this isn't my first build I can say from experience that you need to determine what your goal is. I will probably go with Denis Welch aluminum heads (fast road), cam, and new forged pistons. Considering what else I've done this makes the most since.
John

Welch pistons or others?

 

[jcsb]

Welch pistons or others?

The Omega pistons sold be Welch.
John

 

[dougie]

I gas-flowed and matched ported my stock iron MM head, then installed the larger Welch valves when I first built-up my race/street motor and made the hp gains others have seen with the complete DW aluminum head. Starting my 3rd build on this motor now, I'm still not ready to drop the 3K on the aluminum head. And for me, I could really use the weight savings on the track. On a street car, I just don't see the benefit. If you know your way around a porting tool, there's a lot of good information on how and where to make the improvements to see real gains at a fraction of the price.

Here's an example: https://www.popularhotrodding.com/enginemasters/articles/hardcore/0412em_porting_cylinder_heads/

 

[DerekJ]

Totally agree with Dougie. The Welch head is a beautiful thing and very nice to have but in terms of getting more bang for your buck its just not worth it as you can achieve the same thing with an iron head. The main benefit of the alloy head is to remove about 30 kilos of weight from the top of your engine which makes a difference when racing.

If you are going for a fast road set up with twin 2 inch then I recommend the Dennis Welch DWR8 fast road cam. IT has great torque range that starts around 1000 rpm. I had that set up on my car together with the exhaust manifolds and 10.1 compression ratio. That gave me 160 bhp (honest bhp) at the flywheel. Doesn't sound a lot but remember that an original BJ8 measured in a similar way only puts out about 130 bhp, not the advertised 150bhp.

 

[steveg]

The 150bhp/130bhp could be the difference between SAE gross and SAE Net/DIN. Late '60s was around when the gov't mandated the change in describing horsepower. My '67 Alfa started out at 125bhp then became 109bhp. Needless to say I always preferred the latter.

 

[jcsb]

The Denis Welch cam DWR8 will be what I use. Since I've don't know what to expect when I take the engine apart all things are undetermined now.

John

 

[DerekJ]

Steve

The difference is simply due to the fact that the original numbers were obtained with the engine on a bench with no parasitic equipment or loads on the engine. A standard BJ8 measured on a rolling road will give about 130-135 at the flywheel.