Spridget Tech Talk (MG Midget & Austin-Healey Sprite)
I posted on my previous post of some progress that I've made, but not sure that people are viewing it. Should I start a brand new post when showing how it's coming along or just keep it up with the original? I was hoping for some input that might make this project better.
This is one of the photos I attached to the original post.
This will be an interesting project to follow. I personally would prefer a series of new threads as you go along.
Well, not to be contrary or anything, but I like things in one thread for continuity's sake. Every time a comment is made the thread will float to the top of the list. But that's just me; I could be wrong...
Good luck with the project.
Cheers,
Glen
The engine is apart now. I'll have the crankshaft balanced and will balance the pistons and connecting rods myself. I'll be putting B main bearings in for strength. Just found that I need to have the head rebuilt. I'll make sure that the seats are cut at 3 angles. I don't think I need going with larger valves since the turbo will kick in at about 1500 RPM's. The extra torque at low RPM's might be nice, but I'll settle for this.
An SUHIF4, which should be good to 100 hp, so I've been told. I set the carb plate up to go larger if needed.
Glen,
Studying on the 1500 I've found that the bottom end is the weakest link in the engine and that balancing and original MGB main bearings are the best. For now I'm leaving the head stock other than a regrinding and new valves if needed. An oil cooler will be added for the turbo, I've never had problems with cooling in the past. I've rebuilt the front end and lowered the car. I'm not sure what I'll be doing with the brake system at this point.
I'm doing this for my pleasure and not as a race car. I just want the power for fun.
Roger the fun part! The oil cooler for the turbo is defintely a good idea. You might need some additional engine compartment venting as well, but you won't really know until you have it running. Will you be adding gauges for oil pressure or temp and water temp in degrees?
Glen
After looking at this for awhile , I have a concern. Is there going to be an issue with having the air/fuel mixture in the turbo. Shouldn't it be a blow thru set up? I'm not a turbo design expert, but have tuned on dragsters using turbos as far back as the 70's. The chevy straight six had a single holley with a blow thru bonnet made out of an air filter housing. Also tuned on a pinto motor that used one big bore hilborn injector plumbed in between the turbo and intake.
There are lots and lots of "sucker" turbo applications. Some injection turbos ("blower?") also have injectors upstream of the turbo to cool the intake charge.
Tuning is a PITA (from my understanding, I don't have a gas turbo vehicle) with the "blower" setup.
Of course going FI will solve all that!
Edit to say: Oh, start a journal entry and just "guide" people there once in awhile. Lots more photos possible!
Thought of your project while reading this from a fellow turbo builder. Neat idea for putting a "bead" on the boost tubes so they don't blow apart.
http://www.dsmtuners.com/forums/articles-turbo-system-intercooler/307563-how-bead-your-own-intercooler-pipes.html
I’ll be putting an adjustable blow-off valve where the original was on the turbo. I have seen both the blow through (for down draft carbs) and the “sucker” type (for side draft carbs). I will be adding A/F, boost and oil pressure gages for the setup. I’m also adding an oil cooler to the system and will have water flowing though the turbo. I'll probably be adding a new electronic ignition system also.
No photos yet, I’ll do that after the engine rebuild. Getting close though.
Good idea on the bead. I welded beads on my intercooler pipes on my 2.3 turbo Mustangs.
http://i177.photobucket.com/albums/w224/mgman75/100_5931.jpg Keep it up. Love to hear more on it Maurice
Ok, I'll bite, what compression ratio, and how much boost?
Be careful with the pop off venting. On the air cooled VW's mentioned earlier . a pop off mis vented is still behind the driver , and on its way out of the car quick.
Speedracer to answer your questions. I started a topic in the off topic area so as not to steal this one. If got more questions be glad to answer there. Thanks Maurice
http://www.mgexperience.net/phorum/read.php?47,1277222
