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Hello Snowman!

What is the latest?

MBHD


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Sorry y'all didn't mean to just completely disappear. I'm still here. Had a summer busy full of nothing with no money to get anything done. The intercooler was the last thing I had gotten done on it.

It still runs. Pretty sure I broke a ring just like last time. I've been pretty careless and aggressive with the timing to where I could hear some audible pinging on hot days. Aw well. It has one cylinder that pushes out some blow by every revolution but I'm going to run it til it won't run no more.

I get to come home from college every few weeks or so and enjoy it on the weekends.

I'm actually take it to the Buick GS Nationals with my dad in a couple weeks in Bowling Green, KY to show it off to all those big block Buick guys and their silly V8s. Haha I'd actually end up being more akin to the 100 turbo v6 grand nationals and t-type regals there.

Don't know if any of y'all had ever seen this video but I watch it from time to time when I'm feeling down at college. Cheers me right up!!!
http://www.youtube.com/watch?v=-tjbeAnabM0&feature=c4-overview&list=UUWctOnJoE2bQXMcaHqiwpdA


69 Buick Special Deluxe. Intercooled Turbo Chevy 250 @ 15psi on a stock long block. It's kinda fast.
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Good to hear from you. Some good videos.


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 Originally Posted By: snowman4839


Don't know if any of y'all had ever seen this video but I watch it from time to time when I'm feeling down at college. Cheers me right up!!!
http://www.youtube.com/watch?v=-tjbeAnabM0&feature=c4-overview&list=UUWctOnJoE2bQXMcaHqiwpdA


You and me both! Sounds awesome.

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Looks pretty fast.
At least it's not completely blown. \:D

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Did You watch Josh's other videos? Plenty of self incrimination there. Josh cover your plate and your face! \:D


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Pshhhhhh. I can outrun those cops easy.
But in all seriousness, a cop has to see you for it to be ticketable. The only thing they could use these videos for is if they confiscated them while they caught me on video


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Several years ago when my son was going to college in Texas a judge used something he had posted on a hot rod forum to rule against him in traffic court. I thought it was pretty funny.


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 Originally Posted By: Beater of the Pack
Several years ago when my son was going to college in Texas a judge used something he had posted on a hot rod forum to rule against him in traffic court. I thought it was pretty funny.


I've seen that elsewhere.

It usually requires the poster (usually the "star" of the video) to positively identify themselves in some way, and claim responsibility for whatever "Mischief" they managed.


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This was even funnier. He got a speeding ticket and tried to talk his way out of it in a letter by arguing that his car couldn't go that fast because of the 4.27 rear gears and the rpm limit of the stock engine for his car. The judge came up with info he had posted about his supercharged engine and the over drive trans. What we post is all out there. If someone collected all of our posts from all the sites we go to they would have a lot of stuff about us. It's spooky when you think about it.


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Yeah, I know what you mean! Uh oh, got to go, someone's knocking at the door..... \:D



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Repost of previous post.

Questions, after adding the intercooler & all that piping, did you notice any more turbo lag, takes longer getting into boost?

Does the engine run any hotter having that big intercooler in front of the engines radiator?

What is the actual intercooler you bought? Specs, bar & plate correct?


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Not really any longer getting into boost. Maybe another 100-200rpm til max. I get 15psi by about 2800rpm in first (which takes a split second to rev through) which carries over into the other gears.

I haven't noticed the engine running running any hotter. There's a good like 2 inches between the intercooler and the radiator so there's good ventilation.

31" x11.5" x 3" FMIC FRONT MOUNT BAR AND PLATE TURBO INTERCOOLER from ebay. I've touched the piping before and after the intercooler and there's probably a 100F degree difference so it was a great investment.


69 Buick Special Deluxe. Intercooled Turbo Chevy 250 @ 15psi on a stock long block. It's kinda fast.
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 Originally Posted By: snowman4839
Not really any longer getting into boost. Maybe another 100-200rpm til max. I get 15psi by about 2800rpm in first (which takes a split second to rev through) which carries over into the other gears.

I haven't noticed the engine running running any hotter. There's a good like 2 inches between the intercooler and the radiator so there's good ventilation.

31" x11.5" x 3" FMIC FRONT MOUNT BAR AND PLATE TURBO INTERCOOLER from ebay. I've touched the piping before and after the intercooler and there's probably a 100F degree difference so it was a great investment.


Snowman,
that's great!
Getting 15 psi by 2800 RPM , glad you did not use a .96 A/R housing, that would have been a lot more lag.
Who suggested for you to get that small of an A/R & turbo anyways? ;\) \:D

So, altogether, how much was the intercooler & piping?

Also, you are still driving it around? These inlines 6's are hard to blow up naturally aspirated, super/turbocharging, that's another ball game.

Any plans on a new engine combo?

MBHD


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How much power do you think your making realistically with 15 lbs of boost.



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 Originally Posted By: CNC-Dude #5585
How much power do you think your making realistically with 15 lbs of boost.


That is a good question. My guess would be maybe 250- 280 @ the wheels?, but that would have to be all cylinders holding pressure.

Just a guestimate mind you.
Not sure if he had run it @ a track or done some "G" -tech devise or "IPhone" or smart phone app?

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Hank I'm glad you started this thread to keep most of Snowman's info in one spot. Snowman I'm glad you put it here and are keeping us up dated. It has been fun to watch you learn, use your knowledge and become a real danger to society.


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A "Snowman" is a fairly rare sight down there to Memphis, but there used to be some fairly serious folk building some serious machinery in those parts.

This Snowman has learned just enough to be truly dangerous, but we may hope that he will now apply what he has learned in building an engine that will take the boost he craves and a chassis that will enable him to survive it. That will demonstrate that he has learned his lessons well. His videos remind me of other times and other places -- long, long ago -- when some of us moved 'way out beyond our knowledge. God was kind to fools then, too.

God's Peace to you.

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Haha good call on the A/R and sizing MBHD
The 3" aluminum piping was a $100 kit on ebay. I used every single bit of it too. The intercooler was like $140 I think so with shipping and whatnot, I'd say it was $250 and like 3 hours of modification and fitting to get it operational.
That was probably the easiest install of anything I've done in the car. Like I hit no snags, I had the idea of what I had to do, and it went together like friggin butter.

I feel like with my setup right now, I could make like 280hp with all cylinders holding but I'd say it's like 240hp or so right now. Plus I don't know how it feels in lower gears because it slips as it gets into the upper boost levels. It doesn't hold to the wheels at all with it in first (which is basically a burnout gear because it probably only goes to like 21mph). Second it starts to slip at the end of the gear.
Not bad for slapping a turbo on a stock engine

I would like to supercharge with a cheap eaton m90 at some point down the road. Superchargers have tickled my fancy recently. Maybe it'll transform into a twincharged system for sh*ts and giggles.

As for now, I'm ready to actually get a block prepared like it should and slap the turbo'd head and manifolds on it. I've been itching to get a turbo cam and valvetrain and some head work. Maybe forged internals if I can find some. But that engine work and a clutch and I feel like I'd be in buisness.

PLUS IF I COULD FIGURE OUT WHY IT LEANS OUT AT THE MIDDLE/END OF 4TH THAT'D BE GREATTTTTTTTTTTTT. I can full speed runs now because I have the fuel system to support it but I don't understand why because my A/R jumps up like 3-4 points as I get into the middle of fourth after starting from a dead stop. I can't think of anything that would cause that since it works so well everywhere else.

And no I haven't run it at a track it wouldn't pass spec because of my little oil leak at the back of the oil pan.


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Snowman,
remind us of your fuel system.
Fuel pump being used.
Hose diameters, fittings what size. Some fittings look big on the outside but are internally small.

I know for when I was blowing though my DCOE Weber carbs, I needed the largest needle & seat they offered, other wise it would run out of fuel towards the top of 2nd gear (TH350)

You could install a larger needle & seat for the carb.

As far as in getting lean in the middle & to the end 4th?
Sounds like it is running out of fuel.
What is the max output pressure of your fuel pump?

Check that you are getting full voltage @ your electric pump, could be dropping down when a load is applied to the pump?

Before this engine really blows up for good, try & do some "G" tech testing, smart phone app or something, this is interesting we would like to hear about, well I know I do anyways.

I use a Beltronic Vector FX2 http://www.beltronics.com/manuals/gx2manualrev1.pdf

MBHD


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Did you outrun your dad yet?


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I'm almost ready to get a new cam but I was thinking. I remember that the stock hood is really restrictive so would it even be worth it to replace the cam before the larger valves and porting?

And is there any problem using the stock rockers and pushrods with a new turbo cam? I'd imagine I'd need stiffer springs though.

The plan for the near future is get a turbo cam finally. Then run that for awhile. Then when I get some more money and time, take the head back off and get larger valves and do some head work (maybe lumps).
Then after all that, the only place I have to go is eventually getting forged internals or meth injection. It's almost complete! (I use that word loosely)


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When putting in a larger cam, it is best to use springs designed for the new lift and rpm you desire.
Why not wait until the head can be worked up. I like to cut the valve seal area down and install new design seals. They allow more clearance for lift.


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 Originally Posted By: snowman4839
I'm almost ready to get a new cam but I was thinking. I remember that the stock hood is really restrictive so would it even be worth it to replace the cam before the larger valves and porting?
And is there any problem using the stock rockers and pushrods with a new turbo cam? I'd imagine I'd need stiffer springs though.
The plan for the near future is get a turbo cam finally. Then run that for awhile. Then when I get some more money and time, take the head back off and get larger valves and do some head work (maybe lumps).
Then after all that, the only place I have to go is eventually getting forged internals or meth injection. It's almost complete! (I use that word loosely)


Yes the stock hood/head is restrictive. \:D
Yes, you will see a gain in power w/a better suited camshaft, even w/a stock head. It will not be leaps & bounds more power as it would w/a modified cyl head.
Worth it to change the camshaft w/no other changes, not really.
Yes you can still use the stock rocker arms, and stock push rods.
It would be a good idea to use new rockers & pushrods if it's in the budget though.
Need correct valve springs w/new camshaft.

I would get a custom grind camshaft from Comp cams.
A wide lobe center camshaft of 114 or wider for a street car that needs mileage also.
The roller camshaft I have, but not used yet has a 115 lobe center. But @ .600" lift & 240 degrees duration @ .050. it should rev pretty high w/a turbo.

On your current engine, have you done a compression check?

My V-6 Syclone stock head is pretty restrictive. W/a 1.94" intake valve it can flow 155 CFM @ .500" lift
here is a pick of the high swirl restrictive vane.



Here is a pic after I started removing this obtrusive vane.


Stock:


Vane removed: \:o



Sorry for the blurry pics.


MBHD


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Hank, good pics (blurry or not they illustrate your point) do you have any of what you do to the exhaust? (looks like that isn't the best either.


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Thanks for the reply,

I just compression checked the cylinders this weekend. #2 is at 0psi haha so it's gone. Gonna pull the engine over christmas break and assuming the piston isn't busted, going to re-ring all the pistons with the rings I got gapped for the other engine that I never finished. That'll at least get it running. Now I can either get a cam around christmas time and throw it in there to get the car mobile and have some more fun with it.
Or I could get the cam anyway and slowly work on the head porting and paying for the larger valves and head machining as I have time. Maybe get it running in the spring.

As for the rockers, is there any advantage to upgrading rockers? I mean the only thing I can think they'd be used for is increasing lift assuming you get rockers with a higher ratio. Aren't stock rockers 1.5?

Now as for the actual headwork, I have a few options: smooth out the runner walls and don't touch the bolt boss, grind down the boss into a wing shape, cut out the bolt boss, or cut out the bolt boss and add a lump port.
I heard that cutting out the bolt boss was a bad idea because it lowers the port velocity. But would that help/hurt/not because of the fact that it's boosted?


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 Originally Posted By: Nexxussian
Hank, good pics (blurry or not they illustrate your point) do you have any of what you do to the exhaust? (looks like that isn't the best either.

Nexxussian,
I have not ported the exhaust yet. What your are looking @ is the heat cross over, not the actual exhaust port, not sure if you thought that was the exhaust port? Cross flow head SBC/V-6 same difference. \:D
MBHD


 Originally Posted By: snowman4839
Thanks for the reply,


I just compression checked the cylinders this weekend. #2 is at 0psi haha so it's gone. Gonna pull the engine over christmas break and assuming the piston isn't busted, going to re-ring all the pistons with the rings I got gapped for the other engine that I never finished. That'll at least get it running. Now I can either get a cam around christmas time and throw it in there to get the car mobile and have some more fun with it.
Or I could get the cam anyway and slowly work on the head porting and paying for the larger valves and head machining as I have time. Maybe get it running in the spring.

As for the rockers, is there any advantage to upgrading rockers? I mean the only thing I can think they'd be used for is increasing lift assuming you get rockers with a higher ratio. Aren't stock rockers 1.5?

Now as for the actual headwork, I have a few options: smooth out the runner walls and don't touch the bolt boss, grind down the boss into a wing shape, cut out the bolt boss, or cut out the bolt boss and add a lump port.
I heard that cutting out the bolt boss was a bad idea because it lowers the port velocity. But would that help/hurt/not because of the fact that it's boosted?


Snowman,
your piston is gone, sorry to say, so plan on it being busted.
If you are not going to use larger valves, do not remove the intake boss.
Shape the intake boss into a wing shape.
Stock rocker ratio is 1.75.
Stamped steel rocker are inaccurate, when you actually check them for there ratio, they will be all over the place.
One could have a ratio of 1.7, another 1.68 & so on, you won't get full lift on your valves & some could be more.

Full Roller rocker arms will give you a true actual ratio, less guide wear & less valve stem wear, & could give you more power.

If you are going to install larger valves, then remove the boss & install the lumps.

Do not remove the boss w/out installing the lumps, you still need port velocity even though you are turbocharged.

Your car is a street car, not a race car, & having low port velocity will cause it to get into boost later, more turbo lag.

MBHD


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Hank

I see the heat riser (crossover) port too, and a valve guide boss that appears to be the size of my thumb.

I figured slimming the guide boss some and blending it into a relatively smooth turn to the roof of the port should help, especially in the ports without the crossover. \:\)

If you haven't got that far, no bigee. ;\)


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OK, just checking.

Right now my main concern is the intake port.
I am trying to see if I can get these heads to flow somewhat descent so we can still use these stock heads instead of the better flowing 96 & newer Vortec heads.

You are correct about the guide boss, it does seem a bit larger than the standard SBC heads, will work on the exhaust port later.

MBHD

Back to our Turbo 250 5 cylinder 69 Buick special. \:D


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so the only benefits of upgraded rockers is slightly less rolling resistance and MAYBE a hair more lift assuming the rocker ratios are inaccurate? Seems like the very last thing to add if it's even necessary at all

EDIT: How do you know at what point more lift stops being beneficial and you just need to increase valve size for more power?
And it seems like if anyone was going to get a cam, they would just get the lobe separation and overlap correct for the type of engine and desired RPM range and then get the cam with the biggest lift possible. I know that's simplistic and there's a lot of parts to choosing a cam but is there any detriment to running the highest lift possible without hitting the piston with the valve?

Last edited by snowman4839; 10/30/13 02:31 PM.

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Putting a cam in an engine that has a lot more lift than what the head is capable of having flow for is pointless and a step in the wrong direction. Its at that point that additional head work is required to get the most benefit out of the combo. Doing the head work with the bigger valves and lumps will be the best money you will ever spend. It will provide the biggest increase to your engine and is well worth the money and effort. Even if you put bigger valves in your head and cut out the bolt bosses but didn't put the lumps in at this time, you can always go back and install them later when you have the extra money. Tom's dyno testing also covered this mod to the same head with and without lumps and showed it still have good power increase by itself. But at least you will have the bigger valves in there and might not get you there 100%, but you will still get a huge benefit from doing just that.



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holy jesus. Didn't realize valve jobs/cuts work were $500+. I mean is the most cost effective upgrades at this point to cut out the boss and get a new cam?

I'm getting some conflicting info here. I read on the other page on this thread that cutting out the boss had a power increase and the lump ports added even more. So would cutting out the boss by itself increase power but delay responsiveness?


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Just think that before the lumps were ever thought of that this was the main way these heads were ported. And yes you get as much of a gain from it as you do installing the lumps also. Tom's testing didn't show there was any lag or delay in power from the lump/no lump tests within the same head or cam combos. But yes, also adding the lumps did bump the power a little higher than the same head with only the bosses removed and everything else remaining the same. But while your already this far, it doesn't cost much more to go ahead and install the lumps.



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I have not seen Tlowes dyno tests, but was there a test w/the boss removed, lumps installed & stock sized valves? Results?
I would think not much of any gain w/stock valves. Anyone?

Snowman, the stock rocker arms can only go so far with lift, anymore lift needed, you would have to grind/clearance the slots in your rocker arms, hardly done anymore, since there are many rocker arm companies that you can buy from.

Roller rockers can help make your valve guides last longer, (less wear) Our valve guides are short in our siamese heads, & w/the 1.75 ratio, it is harder on guides also, so they wear quickly as compared to other cyl heads w/longer guides & smaller ratio rocker arms.
Roller rocker arms will not cause your valve stem tips to wear & mushroom either.

I forgot @ what point in lift the stock rocker arms start to hit the rocker arm stud? Anyone???

For a street car, you do not need to go with that much lift, .550" lift is the most I would go with as far as lift is concerned. Heck, .510" lift is fine.

Just remember snowman, all the hp & torque is made through your cyl head, you get a much better performing engine w/a well prepped cyl head, if you do not do much of anything done to your cyl head,,, don't expect much out of your engine then.

If you just cut out your boss & do nothing else, you most likely will not see any gain & would not loose too much response because you still would have the small 1.72" intake valve.

Snowman,,,, Changing out your camshaft to a better suited turbo camshaft will give you more of a gain in power than if you were to cut out the boss, install lumps, & keep your stock sized intake valves.

MBHD


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Hank, there was a test with larger valves and lumps installed and the same head with just the bolt bosses removed, but not with the small stock valves. There was also a head tested with lumps and the stock 1.72" intake valve, but your right, not much gain there. It's only with the larger valves and cam changes that you start to see some good increases.



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Alrighty guys. Long time, no see. I know. I've just been cracking away at school with little to no time to get back home and even less money than time.

But....

I have a job at the University of Washington in St. Louis doing computer science research and a couple weeks in the summer before and after my work schedule free plus now I'll have some money for it. So here's what I'm thinking...

I just got out of classes yesterday. I get home, take the head off the engine and take it all apart, order the new bigger valves (1.9" Intake 1.?" Exhaust), figure out some better pushrods and rockers to get, and then take that all to the machine shop and have them magnaflux the head then plane (if needed?) and cut the head for the bigger valves (I'm assuming the rest of the valve job would be done along with that).
Then pay them as I get my paychecks over the summer to do the work as I can afford it and nearing the end of the summer, find another block to replace the 2nd one that I broke and go pick it up to swap under the new head. Call comp or lunati and have them grind me a custom turbo cam and have that ready to go after my job ends.
Then take my new head and valvetrain, put it onto the beater block and have some fun!

Can somebody point me in the right direction for the valvetrain parts? I still have no idea how to pick rockers. Am I going to need to remove the studs and use those BBC rockers? What pushrods would I need with that? And where do I get the larger 1.9"/1.?" valves?

Thoughts?


69 Buick Special Deluxe. Intercooled Turbo Chevy 250 @ 15psi on a stock long block. It's kinda fast.
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Snow man tom lowe (tlowe) on the site has all the parts you need valves would be 1.9 in and 1.6 ex has turbo cams screw in studs valve train kits but the deal with push rods is you need to buy a push rod measuring tool once you get it all back together and adjust it up or down probably up to get that rocker to be sweeping past the center of the valve cap they sell one on summit for like 16-20 bucks or something like that. Or yu can aneal an old push rod so you can cut it and tap both pieces for very small allthread i ordered my custom pushrods from smith brothers they did an excellent job and it was very fast getting them

Happy inlining


Josh
72 gmc lwb air ride 5 speed (soon) turbo 292 II# 6102
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My 1st post.........hats off to snowman.......just read all 18 pages. Nice to see a bunch of good experienced people eventually set their egos aside for the good of the thread..........I've been playing with twin turboed dmaxes for about ten years.
Threw away enough money to buy Miami just black smoked it away. I have a 66 c10 I'm determined to turbocharge.......6/8 psi.....more for the novelty than performance. Lots of good info here thank you all. Got a Clifford intake and a spa exhaust and a big time diesel builder build me a fast spool big whistle.
T4 I think. Scored the intake and the holly on eBay today it's already setup to push thru and basically new.........gonna have lots of questions.......?Just couldn't bring my self to do a v8........ Prolly would save some money......I just have to be different.


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Welcome sdaver! Congradulations on your first post maybe you ciuld start a build thread in truck talk that way we can see your ride as well;)

Good luck to you i know i'll be following your thread


Josh
72 gmc lwb air ride 5 speed (soon) turbo 292 II# 6102
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