Turbo on a 235 inline. ?'s what does close tolerance mean?

Just make sure you've got a wideand o2 gauge that reads 11.5 at wot, and your timing is retarded in accordance with your boost pressure.

 

alright i will just tap it into the side cover.
but your sure that my stock oil pump has enough power to move the oil through the relocated oil filter (that i will mount below the turbo) and then through the turbo (above my tap on the side cover) and drain back into the side cover?

and why do i need an o2 gauge?

how do i set my retard my timing in accordance with my boost pressure?

 

It's amazing just how little oil a turbo needs. There are more cases of too much pressure and volume than from oil starvation. Your side cover should be adequate for the return, just make sure it is lower than the turbo so oil doesn't remain in the drain piping.

The only reason for having an O2 sensor is if you are running an AF gauge or some tuning device that would need it. I would however recommend some sort of boost timing control like the the MSD 6-BTM.

http://www.msdignition.com/Products...log/6462_-_MSD_6-BTM_Boost_Timing_Master.aspx

step on over to www.theturboforums.com specifically http://www.theturboforums.com/smf/index.php?board=13.0 for the blow through guys. They really do know how to make this work. There is even information on how to modify your carb for fuel enrichment under boost, clever stuff!

 

thank you very much for that link!!! that covers alot of my other questions haha

one other thing though, where about is the tap where i would connect an oil pressure gauge? is there already a place on my engine? because why would i buy the oil filter relocator kit if im going to just drain it back in to the side cover because with the kit i would drain it back into the engine in the same spot.. loke here http://www.autozone.com/autozone/ca...it-Perf&fromWhere=&searchText=&_requestid=284

also do you think i REALLY need that msd box?
im really not trying to cut corners but my buget is VERY tight and if i could run with out it for awhile i probably will with my factory points type.

 

The two most important things to consider when boosting an engine are the air/fuel ratio and timing. You want the air/fuel mixture to richen as more boost is added. You also want timing to retard as boost increases. Making sure of these two things will help avoid melting pistons, blowing head gaskets, cracking rings, detonation etc.

 

See the oil pressure sending unit sticking out of the side of the block six inches or so ahead of the bell housing and behind the generator? Just tee into that for your oil.



If you were to tap into the oiling system to create a full flow oiling system, then a kit like this would be nice to have. But I suspect in order to do it properly the pan is going to have to come off.

And yes, I would recommend the MSD box. The higher pressure created in the combustion chamber is going to snuff out a weak points ignition.

 

Here is an article from www.inliers.org on how to do a full flow oil filtration system. Something I would recommend if you are going to hammer on this thing. Getting all the available oil pressure and volume into the bearings is better than the stock style oil filtering system where a portion of the flow is wasted back into the oil pan.

It looks like if you were to do this, hole "A" could be used as your turbo oil return.

 

I dont think that diagram applies to me because i have a 250 from the early 70's.
So i think i will just T into the place where you described/ a showed me in the photo and then just drain it back into the side cover.
well that takes care of all of my concerns, except i need to do some more researched on everything im going to have to do to install that msd box.

so now that the points type idea is out, how much boost could i get away with with just an HEI distributor, because there is a vidio on YouTube of a guy with a white elcamino with a turbo 292 and he just has a regular HEI, no msd at all

 

correct me if im wrong but i looked up a diagram for that msd box and it looks like i can keep my points type distributor and all inned to buy is a msd blaster coil and the actual msd box.

its the first diagram about half way down the page
http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Products/Ignitions/6420_instructions(1).pdf

if you scroll down furthur they show a diagram for if i got an HEI distributor. do i need to do that or can i just use mty points type like i described above?

 

Forgot I was responding to two different guys and engines in the same post.

The 250 is a full flow system to start with. You should be fine then.

Yes, you can use your points to fire the MSD box. Look into what the guys on the turbo forums do with the vacuum advance, I believe they limit it or lock it out. The biggest problem you have to overcome with your ignition system under boost is accuracy. More engines have been blown to bits because of detonation and lousy ignition timing than anything else.

 

so my motor has the same oil tap you showwed me in the picture above to get enough pressure to the turbo and then drain back into the side cover?

and by accuracy do you mean just a good tune for the timing?

also on the msd box do i need the little controller to tune it in for what i want like this http://cgi.ebay.com/ebaymotors/MSD-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

or do i just need the box?

also if i do need that little controll knob does that mean that everytime i get on the gas/ make boost i need to reach over and turn the knob up?

 

Yes, on the oil port. As stated in the previous posts, this is where you want to take your oil pressure from and the turbo does not need a high volume supply of oil to function.

I mean accuracy in timing, one errant spark can ruin your day! Cramming an extra atmosphere into an engine makes more power and pushes the safety envelope of operation. This is one of those areas where some extra cash thrown in will really help.

I do believe the control knob comes with the BTM. It is for an on the fly timing adjustment if you need it, the box does the rest for you. The only time you would really need it is if you change your fuel or boost psi levels. Example: good fuel = more timing advance and more power! Cheap fuel = less timing advance and a safe trip home.

 

alright sounds good!!!!!!!!!!

thank you soo much!!!!!!!!!!!!!!!!!

i know where to go if i have any other questions haha

now all thats left is a good 4 bbl intake and a blow thru carb

 

Here are some vids to help you along.
These are for the 230/ 250/292 engines. Tom

http://www.youtube.com/watch?v=PLmUO-fJtH0 walk around explaination
http://www.youtube.com/watch?v=ArfybG3Ofuc See it run under boost.

You can look up my other vids for more. Tom

 

No way! Its you hahaha.

Tom i have watched almost all you vids on youtube. you elcamino was a supposting factor if not the soul inspiration behind the project im atempting on my 250 Nova.

Your Elco is awesome!!! a serious dream car for me ha

A couple questions on the vid of the 250 above are:
what ignition set up do you have?
what did you do to mad that 2 bbl for blow thru application
is the motor really stock? if not what internal mods did you do?
and if it was stock what was the factory hp you got from it? before the turbo and any mods

thank you!!!

 

oh btw a question for everybody.

why wouldnt i just go the megasquirt route and skip all carb ideas?

 

Megasquirt works, more than a few people swear by it.

The shop I use to do my tuning isn't so fond of them. Their claim is that there isn't much of a tuning advantage to doing this over a carb, keystrokes over jets and air bleeds. Of course they are FAST and Accel dealers, but in talking with them building the maps for fuel and timing with the addition of boost is not for amateurs. And if you aren't familiar with electronics or building wiring harnesses, it can be a bit overwhelming.

 

Customnova,
Thanks for seeing the inline path!

The 250 being dynoed had a Clifford 270 cam and put down 285 hp with a 390 4 bbl in N/A trim. With that little 500 2 bbl it knocked down 350 hp. Tq went from 283 to 340's.
The 2bbl is pretty much stock, this same setup with intercooler and 4 bbl will knock down 400 hp even with 5 psi boost. Add more boost and look out.

I run a Holley C950 on the Elco fuel injection. Very easy to tune, at least now. The teething pains were big. Tom

 

Well I got the 261 back from the machine shop. I also got the turbo intake fabbed up and thought I would show you how it looked. For those of you following this and want to maybe do this to your 235/261 I may be selling this set up. I am about broke and still need to buy a hei distributor. clutch set up and a few other parts. I am dying to get this on the road! This would fit under the 49 chevy hood if I took of that ridiculous Predator Carb and put on a regular one.

 

picture of the adapter

 

I agree, an EGT gauge is a definate assett.

That comment attributed to a Clifford Performance tech sounds like the guy is delving into a subject he has absolute no understanding of the concept at all. I have done a lot of troubleshooting/maintenance on turbocharged aircraft installations, including what would be considered 'add-on" installations with Rajay turbos on Continental and Lycoming engines. A motor known for it's lugging performance, downright bullet-proof workhorse motor, like the 235, would be a prime candidate to turbocharge.

 

I was looking for antique boost and egt gauges. Any idea where to find something. The only boost gauge I could think of was out of an old Studebaker Golden Hawk or something that had a supercharger. I guess I could look at some aircraft or military stuff if the boost pressures are still relievant????? I didn't want some new ricer gauges hanging around my dash.

 

I ran a aircraft pyro in my shadow back in the day because it worked the same and was much cheaper. You could also use a "low pressure" (say 0-30) oil pressure gauge to read boost pressure.

 

I have a nice old square face boost/vacume gage. $25 + ship. I'll take a picture if your interested.

 

Aircraft Spruce for aircraft style MP and EGT.

 

tom i do not understand though. how can that 2bbl be stock? how can a regular carb work under boosted conditions in a blow thru setup? i thought you needed a special carb?

also just to clarify, the 250 being dynoed had only a cam and that all and it pushed out 350 horse???

 

270 Clifford cam is not ideal for turbo use, but it works. The head is one built by me. 1.94/1.60 valves, bolt in HI-FLOW lumps, ported. Just normal performance upgrades. Tom

 

any comment on the carb question in the previouis post?

 

Normally a holley carb does need to be modified. For a few reasons.
They need nitrophil floats installed ( I did).
They need mech secondary's, Mine was a 2 bbl
They need the PVCR under the Power valve opened up to flow more fuel. The 2 bbl 500 already has large PVCR. So it could supply plenty of fuel for this size motor.

A 600 or 650 double pumper would have taken more work.

 

A standard carb cannot work properly under pressure as they carburate in response to air velocity. They do not recognize mass, so air under pressure receives the same fuel load as unpressurized air, leading to a lean condition. There are ways to make the carb dump more fuel when pressurized, but they usually an all or none fashion.

The only exception I am familiar with is the Fish carb. It carburates in response to mass flow, not velocity. However, it has issues. The float needs to be modified to prevent it from collapsing under pressure. They also like to ice up and percolate fuel into the manifold like a little coffee pot in hot weather. But they are neat as hell.

Bill