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Topic Review (Newest First)
07-24-2010 01:50 AM
cobalt327 The September edition of Car Craft has an article where they bought a couple eBay turbos and a surprisingly cheap pair of generic-fit stainless steel turbo headers (~$100). This formed the basis for an el Cheapo dual turbo SBC that was in a '55 Chevy shoebox gasser style drag car.

The results were less than spectacular but it DID run (7.20's @ 90 mph in the 1/8 or about 11.4 in the 1/4), and WAS cheap. By the end, it made about 600 RWHP on a dyno and cost less than $2K. Be aware though- little items like a Quick Fuel 850 CFM carb was simply "pulled from the CC carb pile"- so the actual cost is obviously a LOT higher than the number they quote. And the long block wasn't included, either.

Before you get too excited, this only begins to tell the whole story, so I'd suggest you do some serious research before going out and buying a pair of T3/T4 hybrid internal wastegate turbos.
07-24-2010 01:30 AM
Hot Rod Todd I would figure what gas you are going to run your engine on and go from there.
Because your 1000hp build wasnt going to run on pumpgas - well not for long anyway.

I did a 2 bolt mains 454 with cast crank, stock rods, a CompCams blower cam plus some TRW 7.6:1 blower pistons and fitted a 671 on top and then went flash with a set of second hand Bowtie alloy heads. Only ran about 6lbs and made 627 hp.

Strangely, the bottom end never let me down but the used alloy heads did.

I think twin turbos are a great idea, but if I were you I would start with a good block and get some forged internals - rods crank & pistons, and build up from there. You wont see 1000hp unless you spend serious money, but you can get a start point that you can lean on, and learn from there.

All the best with your SBC learning experience
07-14-2010 12:35 AM
cobalt327
Quote:
Originally Posted by majorownage
please point out one of my posts that was in error. *most* of my information has been sourced from others.
I'd be GLAD to!!! Remember- YOU asked for it...

Regarding whether or not to use an OEM 4-bolt SBC block or a converted 2-bolt block, I originally said:
Quote:
2-bolt block w/splayed caps is the preferred way to go about it!
Then brainiac (Duh... how does all that oil get there on my cylinder walls?) pipes up w/the following:
Quote:
Originally Posted by majorownage
2 bolt mains dont have enough area to keep cap walk from happening.

i dont say this...Nelson from nelson racing engines says this...
And- (this is in reference to a 2-bolt cap vs. a 4-bolt splayed cap)
Quote:
He says the caps have more area to contact the block, and are therefore more stable and less likely to walk. With two more extra holes in the caps, there is just not enough contact area between the block and the cap.
He does, does he? I SERIOUSLY doubt Mr. Nelson has ever said any such thing!!!

Provide a link to this info. I looked and see nothing on it. BTW, I'm following this up by forwarding this BS to Nelson- just for grins.

I think you have (yet again) f-ed up by mistaking a 400 OEM 4-bolt block and its supposed weaknesses for an OEM 350 block (two totally different castings, there DA), or have otherwise misrepresented Nelson- who I'd imagine would give you a bi-ch slap for that infraction- I know I would.

For your viewing pleasure, I submit the following:


2-BOLT OEM BLOCK


4-BOLT OEM BLOCK


4-BOLT SPLAYED CAP OEM BLOCK Using Milodon Caps


4-BOLT SPLAYED CAP FULL WIDTH REGISTER BOW TIE BLOCK


4-BOLT SPLAYED CAP DART BLOCK

Surely, even a know-nothing, google professor such as yourself can plainly see the difference in clamping area provided by a splayed cap conversion of a 2-bolt OEM block over a stock 2-bolt OEM block or a stock 4-bolt OEM block.

You see junior, the whole idea here is to provide ACCURATE info. To do otherwise compromises this forum's credibility. And that's something I will not stand for from you. Too many guys have put too much work into this place to let someone like YOU soil it w/your misinformation.

Consider yourself served.
07-13-2010 05:16 PM
bipolar_camaro
Quote:
Originally Posted by 72highboy390
man why are you still talking about turbos and boost. i thought you made up your mind about building a good street rod engine.

or are you just on here messing around with people.??!!??
"Nevermind. You need to stick to Honda's. Leave the TT383 to those of us with the smarts. VTEC rulez!"


I was telling imsport i wasnt going with a turbo application. Im going to stick with the 355 on a $2k budget to see where that gets me.


As for gaining 125hp per 5psi of boost, I would love to see it as i have yet to see a gain like that. If you could present me with dyno sheets that would be awesome. But as i said " my experiences in the past with import motors", being a 383 has a much larger bore I cant say its impossible because i havent built one yet. Im just basing my estimations off of what i have achieved in the past, but then again you also have to apply the turbo mapping and math to any motor you are wanting to turbo.
07-13-2010 04:59 PM
72highboy390 man why are you still talking about turbos and boost. i thought you made up your mind about building a good street rod engine.

or are you just on here messing around with people.??!!??
07-13-2010 04:58 PM
lmsport
Quote:
Originally Posted by bipolar_camaro
As bad*** as that sounds, Im dropping the turbo setup and leaving that for my smaller motors. Also you are not gaining 125hp off of 5 psi. At 5 psi of boost your only adding about 20-30% more hp off your initial block power at best. So say you got a 400 horse motor that you want to run 5 psi at, say your getting a 25% hp gain out of that 5 psi your hitting 500 horse now. Atmospheric pressure is 1 bar (14.7psi), so if you were to run 14.7 psi of boost you would have twice as much pressure in the chamber as compared to no boost, therefore your hp gain would be doubled. 400 horse turns into 800..

Thats why the most common psi used in boosting is 7-8, at 7-8 your getting a 50%+hp gain on a good build. At least thats how all my prior experiences in the past have been with import motors.

Nevermind. You need to stick to Honda's. Leave the TT383 to those of us with the smarts. VTEC rulez!
07-13-2010 04:14 PM
bipolar_camaro
Quote:
Originally Posted by lmsport
Go with 383, always makes more power. Keep compression below 8:1.

Vortec heads are out. Get some Iron Eagles, 200irv, big chamber.

280rv cam is out, get a custom ground turbo cam from isky.

No need to turn over 6500.

Figure about 125hp per 5psi of boost up to 15psi, plus the hp of the engine without boost. You will need intercooler and maybe alcohol injection.

As bad*** as that sounds, Im dropping the turbo setup and leaving that for my smaller motors. Also you are not gaining 125hp off of 5 psi. At 5 psi of boost your only adding about 20-30% more hp off your initial block power at best. So say you got a 400 horse motor that you want to run 5 psi at, say your getting a 25% hp gain out of that 5 psi your hitting 500 horse now. Atmospheric pressure is 1 bar (14.7psi), so if you were to run 14.7 psi of boost you would have twice as much pressure in the chamber as compared to no boost, therefore your hp gain would be doubled. 400 horse turns into 800..

Thats why the most common psi used in boosting is 7-8, at 7-8 your getting a 50%+hp gain on a good build. At least thats how all my prior experiences in the past have been with import motors.
07-13-2010 04:06 PM
bipolar_camaro
Quote:
Originally Posted by zildjian4life218
If i were you i would just run the biggest turbo cam that comp has for a hyd flat tappet sbc. Then shoot for 8:1 scr and get forged crank rods and pistons. prolly need a dished piston in the 20cc+ range.

On a 355 build or 383? When i took this motor apart it had a rv cam in it with flat top pistons. So if i cam it harder i would need to go inverted dome on the pistons?
07-13-2010 04:04 PM
lmsport
Quote:
Originally Posted by bipolar_camaro
The budget thing really wasnt an issue. I had about 19k left over from my military money, although i didnt want to spend it all on 1 piece. I still have plans for my wifes prelude sh (no turbos, just an N/A build she doesnt need anymore speeding tickets).

Ok so here we go. Ive got the 355 block already; should i stay at 355 or go for 383? In my opinion Im guessing the 355 would be an easier build. Question is, parts... Like im guessing the vortec heads would be nice for it and not to costly. Cam choice, I have a brand new 280 rv cam now, or should i go a little different? Crank, most likely el cheapo forged crank, forged rods and pistons. I know you build the motor for certain rpms, to be honest i dont want to spin the motor faster than 7000 because i dont care for the sound. So anything else i should be considering?
Go with 383, always makes more power. Keep compression below 8:1.

Vortec heads are out. Get some Iron Eagles, 200irv, big chamber.

280rv cam is out, get a custom ground turbo cam from isky.

No need to turn over 6500.

Figure about 125hp per 5psi of boost up to 15psi, plus the hp of the engine without boost. You will need intercooler and maybe alcohol injection.
07-13-2010 04:01 PM
eloc431962 Give me Fuel Give me Fire Give me that which i Desire.



Cole
07-13-2010 03:59 PM
zildjian4life218
Quote:
Originally Posted by bipolar_camaro
The budget thing really wasnt an issue. I had about 19k left over from my military money, although i didnt want to spend it all on 1 piece. I still have plans for my wifes prelude sh (no turbos, just an N/A build she doesnt need anymore speeding tickets).

Ok so here we go. Ive got the 355 block already; should i stay at 355 or go for 383? In my opinion Im guessing the 355 would be an easier build. Question is, parts... Like im guessing the vortec heads would be nice for it and not to costly. Cam choice, I have a brand new 280 rv cam now, or should i go a little different? Crank, most likely el cheapo forged crank, forged rods and pistons. I know you build the motor for certain rpms, to be honest i dont want to spin the motor faster than 7000 because i dont care for the sound. So anything else i should be considering?
If i were you i would just run the biggest turbo cam that comp has for a hyd flat tappet sbc. Then shoot for 8:1 scr and get forged crank rods and pistons. prolly need a dished piston in the 20cc+ range.
07-13-2010 03:53 PM
cool rockin daddy Wow, I think we have found the long lost brothers of MuscleCarGal.

She was going to run E-85 at 15:1 compression for better mileage in a 305!

Majorownage doesn't know how a cylinder head wall gets oiled. Surprised he missed that lesson in Nelson's tutorial.

Then Bipolar is going to build his FIRST sbc build as a 1000 + HP twin turbo set up.

The familly reunions must be a riot.
07-13-2010 03:43 PM
bipolar_camaro
Quote:
Originally Posted by 72highboy390
or like the guy said, "he has no experience with old v8 SB or BB. So drop all the turbo bull**** and help with his FIRST engine build up. hes actually now asking for realistic advice.

and there is a ton of ways to go about this build realisticly if you just search through this forum, and when you get a basic idea of what you want to go for and have some concrete plans. fire the questions left right and center.

The budget thing really wasnt an issue. I had about 19k left over from my military money, although i didnt want to spend it all on 1 piece. I still have plans for my wifes prelude sh (no turbos, just an N/A build she doesnt need anymore speeding tickets).

Ok so here we go. Ive got the 355 block already; should i stay at 355 or go for 383? In my opinion Im guessing the 355 would be an easier build. Question is, parts... Like im guessing the vortec heads would be nice for it and not to costly. Cam choice, I have a brand new 280 rv cam now, or should i go a little different? Crank, most likely el cheapo forged crank, forged rods and pistons. I know you build the motor for certain rpms, to be honest i dont want to spin the motor faster than 7000 because i dont care for the sound. So anything else i should be considering?
07-13-2010 03:34 PM
72highboy390 or like the guy said, "he has no experience with old v8 SB or BB. So drop all the turbo bull**** and help with his FIRST engine build up. hes actually now asking for realistic advice.

and there is a ton of ways to go about this build realisticly if you just search through this forum, and when you get a basic idea of what you want to go for and have some concrete plans. fire the questions left right and center.
07-13-2010 03:33 PM
cobalt327
Quote:
Originally Posted by bipolar_camaro
Beyond your experience, and yet still telling me I cant do this, basically Im an idiot.
YOUR words, NOT mine, bucko.

Quote:
I admit I do not know much about small blocks, big blocks, what have you. I know Im going in the wrong direction with this build.
Then why are we still having the conversation? If you admit you are going in the wrong direction, correct your course!!!

Quote:
As for now, I need help/advice on how to piece together a decent motor...
If you want to build an engine- ANY engine- start w/a realistic goal and a budget. The pieces and parts will quickly fall into place.

If, instead you start out w/an unrealistic goal and no mention of any budget- just plans for 1000(!!!) HP SBC's built w/OEM parts, well, you're likely as not to be ignored or jeered.

There are all kinds of guys who come on here. Often they're recognised (or mistaken for) as being insincere in their knowledge or their experience or their goals and plans. So far, all you've been "guilty" of, is maybe not thinking through the project before you came here. And, maybe getting caught up in another guy's egging you on.

Anyway, best of luck w/whatever you do. I believe I've done all I can here, be it for good or bad.

At least you can't say no one responded to your post!
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