Inline 250 - T3 Turbo - w/ Video

[Torqueforce]

We demand full throttle footage! I would love to see a trend of turbo'd 60-66's. What are you doing for fuel pump?

[longbed67]

Originally Posted by tincan1966

I contacted Tom Lowe, as well. Man that guy is a wealth of information and a nice guy to talk with to boot!.

My build is starting aith a late 70's 292 short block, decked .015" Using a head from a 1967 250 cid with one of Tom's cylinder head kits(1.84/1.6" valves,locks, springs, etc) Also installing a lump kit.(seemed like some easy HP for less than $100)Milled .020"
Pistoms will be .040" over flat tops for a 307 cid with 2 valve reliefs, on 6" rods. Compression should be in the 9.3-9.5:1 range.
Using a 1990 700R4 trans with a Alabama Converter Co.mild stall.
Rear gears are 3.08:1.
Hoping the OEM torque of the 292, with a little mid-range turbo help will make this a smooth combo for a 4000 lb Suburban

Will be updating my build thread soon with pics from the machine shop and the recent body work.

You should post a link to your build thread on your signature
so we can find it!

[boucher racing]

Originally Posted by tincan1966

I contacted Tom Lowe, as well. Man that guy is a wealth of information and a nice guy to talk with to boot!.

My build is starting aith a late 70's 292 short block, decked .015" Using a head from a 1967 250 cid with one of Tom's cylinder head kits(1.84/1.6" valves,locks, springs, etc) Also installing a lump kit.(seemed like some easy HP for less than $100)Milled .020"
Pistoms will be .040" over flat tops for a 307 cid with 2 valve reliefs, on 6" rods. Compression should be in the 9.3-9.5:1 range.
Using a 1990 700R4 trans with a Alabama Converter Co.mild stall.
Rear gears are 3.08:1.
Hoping the OEM torque of the 292, with a little mid-range turbo help will make this a smooth combo for a 4000 lb Suburban

Will be updating my build thread soon with pics from the machine shop and the recent body work.

Your damn right, TLOWE is a wealth of (tested & proven) knowledge. Just watch your boost level with a compression ratio in that range.

I see you are from Indy, KS. I grew up in Pittsburg, KS and played those INDY tigers in high school. We always had a battle on our hands!

Go for it with the turbo, you won't regret it.

All the best,

Shad

[boucher racing]

Originally Posted by longbed67

You should post a link to your build thread on your signature
so we can find it!

Good idea, I will track it down...

[tincan1966]

Originally Posted by boucher racing

Your damn right, TLOWE is a wealth of (tested & proven) knowledge. Just watch your boost level with a compression ratio in that range.

I see you are from Indy, KS. I grew up in Pittsburg, KS and played those INDY tigers in high school. We always had a battle on our hands!

Go for it with the turbo, you won't regret it.

All the best,

Shad

My target boost range is only about 5-7 PSI. Installing ARP head stud kit, as well as using the Mercruiser marine head gasket set. HP should be conservative, if can get 250-275, I'd be pleased. The head work and the compression upgrade is an easy 30-40 HP gain over stock,with the right intake and good exhaust.(plan is for a single 3" with a Flowmaster Super 44 muffler.
Working on an intake manifold now, debating on Fuel inj or carb. Most likely will use a Holley 350 cfm. Also considered a draw-thru type setup.

I am very fortunate, that my machine shop guy is really into this, and building a 153 cid 4 cyl turbo for a Rambler American, so as I do research and track parts, I get free machine shop work! LOL! We both bought T3/T4 turbo kits w/intercoolers .

As far as posting link to my build thread- I am apparently too computer illiterate to figure that out! LOL. Any help greatly appreciated.

[longbed67]

When you open your build thread and you are on page 1 of it, copy the URL by highlighting it and right click- copy, then go to the quick links tab at the top and select edit signature there will be a box where you can enter text. then right click-paste in the box. and wallah your build thread is part of your

[longbed67]

I actually found your url link took me a couple min but I found it


http://67-72chevytrucks.com/vboard/s...d.php?t=493462

[boucher racing]

Originally Posted by Torqueforce

We demand full throttle footage! I would love to see a trend of turbo'd 60-66's. What are you doing for fuel pump?

I am using the factory mechanical fuel pump. It is boost referenced from the air cleaner spacer. It is suppose to raise the fuel pressure 1:1.

Top side:


I drilled and tapped a brass nipple on the 45deg edge. This is the bottom side of the fuel pump. The pressure from the boost pushes against the bottom side of the rubber diaphragm inside.

[boucher racing]

Originally Posted by tincan1966

.(plan is for a single 3" with a Flowmaster Super 44 muffler.
Working on an intake manifold now, debating on Fuel inj or carb. Most likely will use a Holley 350 cfm. Also considered a draw-thru type setup.

.

Cool, sounds like you have got a good setup with a machine shop. That helps.

If I can recommend, I would get a Offy 5416 and run a Holley 2300 500cfm carb, and look into a bullet style muffler (straight through design). The turbo quiets down the exhaust note.

Good Luck

Shad

[tincan1966]

Originally Posted by longbed67

When you open your build thread and you are on page 1 of it, copy the URL by highlighting it and right click- copy, then go to the quick links tab at the top and select edit signature there will be a box where you can enter text. then right click-paste in the box. and wallah your build thread is part of your

I knew it would be stupidly simple!!

Thanks for the help there!

[longbed67]

Originally Posted by boucher racing

I am using the factory mechanical fuel pump. It is boost referenced from the air cleaner spacer. It is suppose to raise the fuel pressure 1:1.

Top side:


I drilled and tapped a brass nipple on the 45deg edge. This is the bottom side of the fuel pump. The pressure from the boost pushes against the bottom side of the rubber diaphragm inside.

This setup is also what I did...Just some more good info on mechanical fuel pumps... if you want to run a 4bbl or double pumper you should run the fuel pump off of a 1984 L6 250 which had a base pressure of 6-8psi instead of the 4-6psi of all earlier L6 250 mechanical pumps. As well boost referenced mechanical pumps are good to 12-14lbs of boost after that, they cant keep up.

[boucher racing]

I finally scored a OFFY 5416 intake, from a member here on the board, thanks Steve.

I finally got the chance to dig in today. The turbo looks in great shape, as well as the up and down pipes.

When I took off the intake/exhaust I was revealed an issue. I had noticed oil/gas stains coming down from that area and running down the block. I kept on trying to clean it up but could never see the source.

It looks as though the intake was not tight against the block and fuel was leaking from the intake and down the block. Probably caused from running rich and boost pressure.



I am taking my Offy and exhaust manifold in to get resurfaced, hopefully that will correct the issue.

Boucher'


and also an artsy pic of my turbo. Praise Garrett!

[longbed67]

Looks like you have your work cut out for ya! How long at a time were you running your truck? I'm wondering if on short trips the fuel was condensating and the intake didnt have time to heat up completely to evap back off...

[boucher racing]

Originally Posted by longbed67

Looks like you have your work cut out for ya! How long at a time were you running your truck? I'm wondering if on short trips the fuel was condensating and the intake didnt have time to heat up completely to evap back off...

I would run it around town, at least 15 minutes at a time. It would reach temp for sure. The way I have my carb setup, cold starts are very hard... no choke horn. It takes awhile to warm up.

Longbed67, I have been wondering about your project, how is it going? From what I have seen, it looks not notch! Very nice work.

Are you using an intercooler? I am still on the fence. I figured, I will install the intake and see where I am at.

Boucher'

[longbed67]

Originally Posted by boucher racing

I would run it around town, at least 15 minutes at a time. It would reach temp for sure. The way I have my carb setup, cold starts are very hard... no choke horn. It takes awhile to warm up.

Longbed67, I have been wondering about your project, how is it going? From what I have seen, it looks not notch! Very nice work.

Are you using an intercooler? I am still on the fence. I figured, I will install the intake and see where I am at.

Boucher'

By get hot, I meant have time for the intake metal to get hot not the coolant temp... As far as choke horns go, I havent seen a blow through set up have one yet on any engine.

I am not using an intercooler and wont unless I turn the boost up over 10lbs. I am using meth injection. I have it setup with a MAP sensor so that when I hit ~4lbs of boost it kicks in. As far as an intercooler goes, I have discussed this topic for the 250 motor in depth with the guys over on the turbo forum they felt I was going overkill with the meth injection, and that an intercooler was completely unnecessary for under 10lbs of boost. I am capping my boost off at 8-10 lbs. The meth injection for daily driving use is a 50/50 mix of methanol and H20. When I go to the track, I will run a 47/47/6 mix of methanol/H20/ nitrometh I am also running a BOV in addition to the wastegate. My build has been at a stand still since the father in law was killed on Oct. 24 in a motorcycle accident. This friday and sat my buddy trummjo on the forum is coming over to finish up the wiring that we started so long ago. Even though we got snow the past two days, they didnt put any salt down, so if all goes well I might see some road time yet this year!

What size downpipe are you running as well?

Adam

[boucher racing]

Originally Posted by longbed67

By get hot, I meant have time for the intake metal to get hot not the coolant temp... As far as choke horns go, I havent seen a blow through set up have one yet on any engine.

I am not using an intercooler and wont unless I turn the boost up over 10lbs. I am using meth injection. I have it setup with a MAP sensor so that when I hit ~4lbs of boost it kicks in. As far as an intercooler goes, I have discussed this topic for the 250 motor in depth with the guys over on the turbo forum they felt I was going overkill with the meth injection, and that an intercooler was completely unnecessary for under 10lbs of boost. I am capping my boost off at 8-10 lbs. The meth injection for daily driving use is a 50/50 mix of methanol and H20. When I go to the track, I will run a 47/47/6 mix of methanol/H20/ nitrometh I am also running a BOV in addition to the wastegate. My build has been at a stand still since the father in law was killed on Oct. 24 in a motorcycle accident. This friday and sat my buddy trummjo on the forum is coming over to finish up the wiring that we started so long ago. Even though we got snow the past two days, they didnt put any salt down, so if all goes well I might see some road time yet this year!

What size downpipe are you running as well?

Adam

Sorry for your loss.

I am running a 2.5" d.p.

It sounds like you have it set up really nice. I am not running a B.O.V. but have thought about it. The only reason I have debated a intercooler is because of heat soak. My truck runs like a scalded DOG! when it gets to running temp, but after running it for awhile and everything in the engine bay gets "heat soaked" the power goes way down. I figured a intercooler would keep the intake charge cool...much cooler. I have put probably close to 1500 miles on it, so I have the kinks worked out.

Good luck on keeping the boost down, LOL. Its hard to bury the temptation because it is so easy to turn it up!

Boucher'

[ole dollor]

i would like to see how this turns out...like it so far..good work

[longbed67]

I am hoping that by running a DEI titanium heat shield over the turbine, and DEI titanium wrapping the down pipe and running a 3" downpipe with less turbine back pressure, in addition to the meth injection, I can limit the effects of heat soak. With the smaller down pipe and having extra exhaust piping setup under the hood like you do, and if you are already experiencing heat soak, you might want to run an intercooler. Also how many core radiator are you running? And did you check your setup with a wideband or plugs, because if your running too lean or too rich you can run way HOT. Since you have everything tore apart right now, I would also consider wrapping your up pipe and down pipe to help push the heat out the tailpipe.

And your 100% right about turning up the boost.... I suppose that's thats always a project for down the road... 4 core intercooler and 18-20lbs of boost....

[longbed67]

Also what kind of fuel are you running and does it have ethanol or lead in it? Ethanol and lead can cause deposits that are white similar to that is on your turbine fins, but if your not running either one, that tells me your running WAY to lean and would also explain why your running hot.

[HouldenCaulfield]

maybe I missed it, what intake were you running originally with the Holley 350? I am thinking of upgrading my Inline 6 with a Holley 350 but wasn't sure if I had to change out my stock intake also.

[boucher racing]

Originally Posted by HouldenCaulfield

maybe I missed it, what intake were you running originally with the Holley 350? I am thinking of upgrading my Inline 6 with a Holley 350 but wasn't sure if I had to change out my stock intake also.

I milled the original 1bbl intake to the size of a Holley 2bbl. It was opening up a can of works though... intake sleeve, voids, JB weld to fill.

You can buy a 2bbl to 1bbl adapter. Naturally aspirated would be fine, but if I were turbocharging it, just get the Offy from the start.

[boucher racing]

Originally Posted by longbed67

Also how many core radiator are you running? And did you check your setup with a wideband or plugs, because if your running too lean or too rich you can run way HOT. Since you have everything tore apart right now, I would also consider wrapping your up pipe and down pipe to help push the heat out the tailpipe.

I am running the original radiator. When I say HOT, its is not overheat HOT, I took it out this summer (103 deg), was in stop and go traffic and it did fine. So, it runs at the right temp. It has never overheated.

I am running a AEM wideband. My afr's are: cruise 14-16 and WOT 10-11. When I pull the plugs, it does not get good fuel distribution, I think mainly because of the intake setup. Two short runners and two long outside sweeps. Inner plugs burn correct, outside plugs burn rich.

I have thought about running a turbo blanket, from some of the youtube vids, it really looks like it contains the heat! Good idea.

Does the same concept work with wrapping the up/down-pipes?

[HouldenCaulfield]

Originally Posted by boucher racing

I milled the original 1bbl intake to the size of a Holley 2bbl. It was opening up a can of works though... intake sleeve, voids, JB weld to fill.

You can buy a 2bbl to 1bbl adapter. Naturally aspirated would be fine, but if I were turbocharging it, just get the Offy from the start.

Thanks for the info. I planned to just do naturally aspirated.
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[67stepsideC10]

Wow sweet build, subscribing for ideas for my 250!

[camaney]

nice, where did you get the spacer for the 2 barrel?