Turbo 200 in 1967 MGB

Hi Guys,
Some of you may have seen that a couple of us MGB owners were experimenting with a 200-6 transplant into an MGB. I'm one of them...
I have a 1967 MGB modified to fit a 200 t5 combo. The engine sits back nice and far and also quite low so balance should be good. The engine/trans combo actually weighs less than the original 4 banger thanks to thin wall casting. I have also fitted a coil over 4-link rear end and corresponding front suspension and brake modifications.

I have an aluminum head on order with Matt, Turbo curved DUI Distributor and am likely going to give the FiTech 600hp power adder fuel injection unit a go. It is on the large size for a NA 200 with aluminum head but should be in a good space with blow through turbo setup. Is anyone else running one on a small six? I have a custom grind cam from Schneider with the following specs:
intake 280 duration 220 @ .050" .450" lift
exhaust 270 duration 214 @ .050" .440" lift
114 lobe center

I picked up 2 Holset turbos to start the build with and will be running a front mounted intercooler. One is a HX35 with about 100,000kms on it and the other is a low mile rebuilt HY35W (internally wastegated). From my research the HY35 and HX35 wastegates are set around 17-20psi from the earlier cummins. Is anyone running a similar sized Holset with the internal wastegate? If so were you able to adjust the actuator far enough to get boost psi to a more reasonable range? What PSI are you finding it boosts to and can the wastegate keep up with boost creep on a 200? I am planning on using the HY35 unless I find it too small on top end then may just switch the exhaust housing/turbine to something more appropriate.

If I don't have to go to an external wastegate right away I would rather not for simplicity. I'm sure I'll have plenty of kinks to work out with the entire setup and having a more straight forward exhaust setup during all the in and outs will be preferable.

Thanks, I would welcome any input and advice. This is my first foray into the Falcon six and turbocharging but not my first engine build. I have gone through a few high performance ford big blocks and mgb engines.

Alan

PS: here is the build thread on the MG Experience forums http://www.mgexp.com/phorum/read.php?40,2895734
 
My experience is that the HX35 is well suited to the 300. I suspect the smaller HY will be perfect on the 200.

I have no experience with the HY series, but the HE351CW wastegate is too small to maintain a low boost level. They can be ported to a size that works. I ran into that with my HX as well. I drilled out the WG hole to one inch and then blended the corners. I used a larger flapper valve for a DSM to cover the larger hole. They were being sold on ebay a few years back.

The wastegate actuators won't be adjustable to a comfortable boost level due to the internal spring. You will want to find a different actuator. I have a 4psi actuator bolted to a modified Holset bracket.
 
Thanks, I thought I might get a reply from you being a fellow MGB owner. I ended up ordering an external gate so I could have in car manual boost control. I found a good solution for wastegate plumbing back into the exhaust that I can post more about once its setup. I guess I will weld or epoxy up the flap on the hy35 and remove the actuator.
 
I would forego the epoxy and wastegate, it won't last with the temperatures in the exhaust. I would spot weld the wastegate arm in the closed position.
 
Why not just hold it closed with a "fake WGA?" That way, if you ever decide to use it - or sell it - you have the option.

Also, you don't need an external wastegate to use a boost controller. The only reasons to use an external wastegate are for installation or flow concerns. Whether it's an internal or external actuator the controls are still the same. What Turbo_B mentioned about modifying the stock wastegate is probably all you need to do here ... unless you want to run 1+ bar of boost. ;)
 
Do you have weight measurements on the two engines for comparison? I figured the 200 at about 300 lbs. My Opel OHC is a hefty little chunk.
 
The 200 with an alloy head is 337 pounds with flywheel.

Iron head, 365 pounds for the early single pattern dressed without flywheel, 385 for the later dual pattern with flywheel.

BMC B series 1798 cc, 335 pounds dressed without flywheel

Rover and Buick 215, 324 pounds dressed without flywheel

The Opel CIH 1900 is very, very heavy. 355 pounds IIRC, 60 pounds heavier than the Holden Starfire Four at 289 pounds. The 1978 UC Holden Sunbirds lost a lot of weight over the nose, and the ohv 1892cc Holden engine with less horspower was quicker only because it was lighter.

The Holden L6 149-202 sixes, 425 pounds, the smaller engines had steel cranks and were no lighter than the bigger 179/186/202 engines.

EFI added 31 pounds to the 202 engine, on a Ford Falcon 250, EFI added 57 pounds.

Internet info on the Opel 2.8-3.0 CIH L6 is totally wrong, the 1983 3.0 L6 was way heaver than a Holden 308 V8, 500 pounds, not 395 pounds.


The alloy headed 3.6 Lotus Charlon, it had arecast heavy duty iron block and a Cosworth alloy 24 valve head, and it might have been 395 pounds. The worlds fastest 4 door sedan.

Peter Brock in Australia did an Opel Monza to Holden Commodore V8 swap, and the 5.0 V8 was 470 pounds, lighter than the iron Cam In Head 3.0 Bosch K Jetronic Opel engine.
 
Nice to see legitimate numbers. My 200 is going lightweight with clamp on aluminum intake, short tube headers, so it will come in under the Opel CIH, but my trans will make back up the difference. Any numbers on the difference in weight between the four main 200 and seven main; block and crank anyway. I'm shooting to keep my car under 2,000 pounds.
 
Hope your still around.

Four bearing 144-170 and 200 365 pounds.

Seven bearing 200, 385 pounds.

The engine weights with alternator are less than these quoted figures...these are with generators fitted.


The last low mount blocks used on some 1981-1983's were most likely heavier than 385 pounds.
 
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