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1275 core

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mightymidget

Jedi Knight
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found a complete1275 engine with transmission, (motor #12C DA 23044) for a fair price off craigslist.

plan to have motor rebuilt by someone, the Trans I will use since they a ready been paired, I have two others.

Are there any upgrades that should be done to improve performance and dependability of the 1275. Head work, Cam.. since motor will be rebuilt

I am already thinking oil filter modification, and distributor work?
 
You are 3 1/2 hours from Acme Speed Shop. Since you are going to have someone do this anyway. I would suggest you take it to Hap - he can help you with the various mods that will make the engine quicker and more reliable.

https://www.acmespeedshop.com/about.html
 
JPSmit said:
You are 3 1/2 hours from Acme Speed Shop. Since you are going to have someone do this anyway. I would suggest you take it to Hap - he can help you with the various mods that will make the engine quicker and more reliable.

https://www.acmespeedshop.com/about.html
Click to expand...

I second Hap at Acme...he can not only build you a great engine, but he can help you understand the different modifications. He was a great help to me on my MGB engine build and I'll use him for my 1275 and my TR4A engine.
Rut
 
I have left messages with Hap and hope to hear from him, the past two times I have talk with him about other work he was swamped with work. Since he his good at what he does he stays very busy.
He is my plan A, but if he is still busy I will go to plan B
 
+1 for Hap. I never used him, but his fix for the recessed blanking plug issue for the 1275's head is definitely one VERY important modification to make your 1275 a more reliable motor. I had my local machine shop duplicate his fix when I had the head on my 1275 redone. I imagine his knowledge of the rest of the 1275 would be equally impressive.
 
back to the original question about upgrades, after some reading on the net I have come up with these upgrades.
1. switch distributor to electronic for dependability, some like "flame thrower"
2. Harden valve seats and guides in stock cylinder head
3. bore .040 over and install 9:7 to 1 pistons which this part number keeps popping up #AE21253, it has also mentioned you can bore out to 1380, not sure about problems if any with this bore enlargement.
4. Don't know if this cam ruins drivable of car but the APT VPN seems to be very popular, along with APT lifters. along with an adjustable cam timing sprocket
5. ARP rod bolts and resize journal ends
6. Aluminum flywheel or lighten current one,

I am not really looking to make the car fast per say, just a high performance version that might have been sold when vehicle was new.

For that reason flywheel mod is out and still researching camshaft,
Hap sell all the parts and I am sure he can fill in the blanks ONCE I have a good feel of what I want and the money to back it up.

Anyone driven a Bugeye with this cam or similar ?
 
Ok, I kinda see where you are going with this and I went down the same path. The number one thing to think about is that the engine is a system and the modifications and choices made must work together. We MG nuts on the forum can offer our opinions, but in order to put together an engine that does what you want it to do you really need to talk to someone face to face or on the phone to use a 'recipe' that's proven. I had a good time building my MGB engine as stated above and Haps advice was without a doubt a huge asset in the outcome. The mistakes that can be made can make a difference between a car you like and one you hate...call Hap!
Rut
 
My advice is to stick with a stock cam or at least something that focuses on low end torque as opposed to high end HP. Most cam modications I've seen result in higher HP at very high RPM (seldom utilized by the typical vintage car enthusiast that is not a racer) at the expense of low end torque and drivability (almost always important to the typical vintage car enthusiast).

Increasing displacement will increase torque and HP at typical driving RPMs (as well as high rpm), so if you want more usable power this would be the way to go. On the other hand, I doubt it will ultimately make enough difference to matter.

Hardened exhaust valve seats are usually recommended because the lack of tetraethyl lead in modern fuel can result in exhaust valve seat recession into the head. However, I personally doubt that this will happen in most of our cars because they are typically not driven enough for it to occur. If it's your daily driver, yes, but that is rarely the case. Probably still a good idea, but perhaps oversold.

I am also not a fan of lightened flywheels for non-race cars. While they result in significant decreases in rotating mass, and thus improvements in acceleration and more responsive shifting, they also cause increased stalling, increased engine vibration/harshness, increased noise, and lower engine life. I don't think the benefits are worth it.

Keep in mind, the engineers who designed these engines were smart cookies for the most part. There is usually a trade off with any design change from the stock engine.
 
mightymidget said:
back to the original question about upgrades, after some reading on the net I have come up with these upgrades.
1. switch distributor to electronic for dependability, some like "flame thrower"
2. Harden valve seats and guides in stock cylinder head
3. bore .040 over and install 9:7 to 1 pistons which this part number keeps popping up #AE21253, it has also mentioned you can bore out to 1380, not sure about problems if any with this bore enlargement.
4. Don't know if this cam ruins drivable of car but the APT VPN seems to be very popular, along with APT lifters. along with an adjustable cam timing sprocket
5. ARP rod bolts and resize journal ends
6. Aluminum flywheel or lighten current one,

I am not really looking to make the car fast per say, just a high performance version that might have been sold when vehicle was new.

For that reason flywheel mod is out and still researching camshaft,
Hap sell all the parts and I am sure he can fill in the blanks ONCE I have a good feel of what I want and the money to back it up.

Anyone driven a Bugeye with this cam or similar ?
Click to expand...

I get all my engine specific performance parts from APT. You can't go wrong there, but I'm not sure about your "1 from column A, 1 from column B selection". I don't see that the high compression pistons and cam make sense with a stock head. The cylinder head is where you will get the most performance improvement in these engines. APT has a range of ported heads, and depending on your goals, they will assist you in making the right selections. If you stick with a stock head, don't bother with more than a 266 or 276 cam (depending on where you want your power band). I'd also stick with the 8.8 compression pistons.

To cover your list items one by one:

1. Get your distributer, either rebuilt exchange or have yours rebuilt and recurved by Jeff at Advanced Distributors. He will fine tune one based on your build, rather than something generic. He has an electronic ignition that is supposed to be very good also.
2. I would go with a basic stage, street ported head, but otherwise if sticking with stock, hardened seats are just fine.
3. I would only go to the next size needed for overbore. This needs to be measured by your machine shop to see how much bore taper you have. .040 could be way too much or not nearly enough. The next step is .060, which is the "end of the line" unless you want to go offset bore (1380). If you go .040 now, your next rebuild will be .060 or putting in new sleeves. New sleeves or 1380 is costly, and again, makes no sense with a stock head and high compression pistons.
4. I already covered the cam. APT Super duty lifters - good idea with a new cam.
5. ARP :encouragement: Resizing rods I consider for be S.O.P for building an engine, as should line bore be checked.
6. Aluminum flywheel... seems like better than 95% of people who make this swap are not happy with drivability on the street. Again, not cheap and money would be better spent elsewhere. Having your lightened a few pounds would probably be better.

Here's a race engine I'm finishing this week. Crank, head, rods, cam, pistons, center main strap, lifters, oil pump, and all ARP fasteners, all supplied by APT

3-15-20151.jpgcamtiming1.jpgcamtiming4.jpgIMGP0036.jpgIMGP0037.jpg
 
very nice Gerard. last thing I want is a race engine, but very nice.
just trying to grab some extra horse power during rebuild of engine. thanks for input.
 
mightymidget said:
very nice Gerard. last thing I want is a race engine, but very nice.
just trying to grab some extra horse power during rebuild of engine. thanks for input.
Click to expand...

Thanks Mightymidget,

I wasn't suggesting you build a race engine, just posted pix so you could see APT parts I used.

There are several stages of ported head. Even the one I'm using on this engine is not a fill race head... nearly so, but not all the way. There are street versions that are less expensive and less aggressive. These engines are very restricted for breathing, and that's where you'll make the biggest gains.

Also, I forgot to mention, for your scenario, the vernier cam gear really isn't necessary. You do want to time the cam, but you'd be surprised how often modest cams come in right on the nose using a standard key in the crank. The worst case scenario is is that you might need to get an offset key, which are only $20-$30, instead of the ~$200 for the vernier cam gear. The cam in the engine I'm building is set for 102 degrees, whereas most stock and mild cams are 106. In your case, it'll be "set it and forget it".
 
Hap, there is a reason he called his business ACME :wink-new:

Good luck with that....

If anybody wants more info, please feel free to contact me for specifics.

Pat
 
Is there any good info on what a street port job that work's amount's to? I'm planning on having my head done locally by a shop that specializes in stock car engine work. They offer a "pocket port" for not much over $100. I know that the area directly around the valves is the most critical.

Kurt.
 
Kurt,
Get a copy of Vizards book on the A series and read his thoughts on the subject. Some places offer an 80/20 service that provides 80% of a full port/polish for 20% of the cost. I would think a $100 pocket clean up would help performance, but don't know how much.
Rut
 
Thanks Nial for exercising your descretion regarding my post (s), for this thread.

You are a brother always.

Pat
 
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