daydreaming - cheap turbo drag car

Well, let's focus on application. What diesel trucks etc can I get that from? I am OK with twins if necessary, but I'll need to know how big. How big is too big? What happens from too big? If too big actually equally more performance but with more lag, I can fix lag with a little nitrous at the starting line, or something like that. I've often heard of retarding the timing to the max to get the turbo spooling while on the two step... so, without going to small, assuming a 350 cubic inch engine at 6000-6500, how big is too big for singles or twins? Where can I get them?

Also, I have no idea what "depending on the hotside" means, other than maybe the size of the exhaust side of the turbo, but I didn't know they could vary...

Thanks -Brian

Travis_K wrote: How cheap are you thinking? IMO, for a low budget turbo drag car you want a ford.

I agree. Gimme a roller 5.0L and a pair of HY35's and I'm set.

tuna55 wrote: Well, let's focus on application. What diesel trucks etc can I get that from? I am OK with twins if necessary, but I'll need to know how big. How big is too big? What happens from too big? If too big actually equally more performance but with more lag, I can fix lag with a little nitrous at the starting line, or something like that. I've often heard of retarding the timing to the max to get the turbo spooling while on the two step... so, without going to small, assuming a 350 cubic inch engine at 6000-6500, how big is too big for singles or twins? Where can I get them? Also, I have no idea what "depending on the hotside" means, other than maybe the size of the exhaust side of the turbo, but I didn't know they could vary... Thanks -Brian

A lot of people mix and match turbo parts. You can use a turbine off one and a compressor off another to build a hybrid turbo. Smaller turbines spool faster with less lag, but restrict the top end and will over rev causing self destruction. Larger turbines have more lag, but less top end limiting. You need to match the compressor to the engine. It needs to put out enough air to maintain boost through the rpm range. A small compressor won't move enough air to keep the engine fed, and a large compressor will move so much air the bov or waste gate will dump, wasting all the energy used to spin the turbo. The compressor also is dependent on turbine side since that is what determines how fast the compressor turns.

Most turbos have a sheet showing how much exhaust volume needed to move so much air at a given boost pressure.

The other option is to find a turbo off a similar displacement engine and go from there. With a diesel turbo I would probably go with a larger displacement given that most diesels turn about half as fast as a gas engine. That is just a guess though and I have no information or facts to back that up. Then again, diesels run massive amounts of boost...up to 50lbs which changes the size needed to make less boost for the same displacement. Lots of variables and with a guess all you can do is trial and error.

With the cost of diesel turbos and the cheapness of turbos on ebay, if I were in your shoes I would go with two turbos sized for 4cyl engines and twin turbocharge it. It would probably cost less than one big diesel turbo.

http://www.youtube.com/watch?v=Qk9uU_3VHT0&feature=related

Taiden wrote:

93celicaGT2 wrote:

Taiden wrote: I know you want a V8, but what about an SR20DET sentra? You can probably break into 10s with 5gs

I'm not sure i see that happening, to be honest. To break into the tens on a FWD car like that, you'd have to have more power than the stock motor will take. Sooo... built motor + big turbo + EMS + expensive clutch to harness the power + 15-20 backup transmissions + slicks + suspension + chassis certification... it'll add up quickly. Buddy of mine has a Neon that runs 10.60s. It ain't no 5G setup.

Well, you can talk to Fred Casey about that. Bone stock SR20DE motor with a huge turbo bolted onto it with a nice clutch and drag slicks = 10.8 ET, hundreds of passes and driven on the street on weekends. The 91-94 SE-R is very underrated.

Linky? I'm not going to sit here and call you a liar, but i'm pretty skeptical of that. SR20de head is going to be a big limiting factor there....I haven't heard of the other strong japanese 4 bangers going 10s with so little work. POSSIBLE exception in the 4g63.

Would LOVE to be proved wrong, though.... would give me inspiration for my 3sgte.

93celicaGT2 wrote:

Taiden wrote:

93celicaGT2 wrote:

Taiden wrote: I know you want a V8, but what about an SR20DET sentra? You can probably break into 10s with 5gs

I'm not sure i see that happening, to be honest. To break into the tens on a FWD car like that, you'd have to have more power than the stock motor will take. Sooo... built motor + big turbo + EMS + expensive clutch to harness the power + 15-20 backup transmissions + slicks + suspension + chassis certification... it'll add up quickly. Buddy of mine has a Neon that runs 10.60s. It ain't no 5G setup.

Well, you can talk to Fred Casey about that. Bone stock SR20DE motor with a huge turbo bolted onto it with a nice clutch and drag slicks = 10.8 ET, hundreds of passes and driven on the street on weekends. The 91-94 SE-R is very underrated.

Linky? I'm not going to sit here and call you a liar, but i'm pretty skeptical of that. SR20de head is going to be a big limiting factor there....I haven't heard of the other strong japanese 4 bangers going 10s with so little work. POSSIBLE exception in the 4g63. Would LOVE to be proved wrong, though.... would give me inspiration for my 3sgte.

The main limiting factor in making a SE-R drag car is the transmission. Stock SE-R 5-speeds can take a max. of 250whp before they bite the dust.

As for heads, mixing and matching parts is pretty simple on the SR20DE, regardless of drivetrain layout. You can easily exceed 250whp with parts from a JDM SR20DET-powered car like a Nissan Bluebird Turbo or any of the Silvia Turbos.

Get a 351 Windsor with a set of GT40 heads (P's can be had fairly cheap, but then you have to worry about headers). A set of aluminum heads for a Ford will be (most usually) more than those for a SBC, but you can find a deal if you look (www.racingjunk.com). You can build a "blow-through" carb yourself (www.hanger18fabrications.com) out of a 4150 Holley. Use a single-plane intake of choice. Use a SINGLE turbo! For a 351W, try to find something with an .82 A/R (or a little bigger) turbine housing. You will have to determine your turbo based on several factors, but keep in mind you may not want to run a really high-stall converter, but rather, take advantage of the torque that is down low.

So: 1978 Ford Fairmont 2-door post, 351W with GT40 heads, cast mani's, HX40 with .82 A/R turbine housing, small block C6 with a 32-3500 stall converter, 8.8 with LSD and 3.27 rear gear. Don't skimp on fueling system. Intercool with a large front-mount or methanol injection.

-Les

BTW, read "Maximum Boost" by Corky Bell.

Futura or die!

RexSeven wrote:

93celicaGT2 wrote:

Taiden wrote:

93celicaGT2 wrote:

Taiden wrote: I know you want a V8, but what about an SR20DET sentra? You can probably break into 10s with 5gs

I'm not sure i see that happening, to be honest. To break into the tens on a FWD car like that, you'd have to have more power than the stock motor will take. Sooo... built motor + big turbo + EMS + expensive clutch to harness the power + 15-20 backup transmissions + slicks + suspension + chassis certification... it'll add up quickly. Buddy of mine has a Neon that runs 10.60s. It ain't no 5G setup.

Well, you can talk to Fred Casey about that. Bone stock SR20DE motor with a huge turbo bolted onto it with a nice clutch and drag slicks = 10.8 ET, hundreds of passes and driven on the street on weekends. The 91-94 SE-R is very underrated.

Linky? I'm not going to sit here and call you a liar, but i'm pretty skeptical of that. SR20de head is going to be a big limiting factor there....I haven't heard of the other strong japanese 4 bangers going 10s with so little work. POSSIBLE exception in the 4g63. Would LOVE to be proved wrong, though.... would give me inspiration for my 3sgte.

The main limiting factor in making a SE-R drag car is the transmission. Stock SE-R 5-speeds can take a max. of 250whp before they bite the dust. As for heads, mixing and matching parts is pretty simple on the SR20DE, regardless of drivetrain layout. You can easily exceed 250whp with parts from a JDM SR20DET-powered car like a Nissan Bluebird Turbo or any of the Silvia Turbos.

Oh, i'm not arguing 250whp.... i could make that reliably turbo'ing a camry motor.... but 250whp isn't going to get you 10s..... I won't even argue 350whp.... but it took over 500whp to get the Neon in the 10s. On slicks.

I just wanna see his build or something.

So basically, the only answer I am seeing here is "go look at the turbo sheets". Right? Where can I find those?

Thanks -Brian

tuna55 wrote: So basically, the only answer I am seeing here is "go look at the turbo sheets". Right? Where can I find those? Thanks -Brian

If you're looking at a fairly common turbo, you can typically find them in google images. Type something like GT35R flow chart/map for example.

Some of the bigger holsets are harder to find the charts for, though.

So how much boost can I run with 8.5:1, forged pistons, aluminum heads, E-85 and an intercooler?

You can run as much boost as your setup can handle, up to the point where you start to go lean, or you start to run inefficiently. This depends on more variables than you have listed. Your fuel system capacity is a limiting factor. Your ignition system's ability to light the mixture is a limiting factor. Your turbo's efficiency is a limiting factor. Etc. etc.

I suggest you go read a couple books and get real familiar w/ the concepts. You'll learn alot more alot faster than asking questions on mssg boards.

Corky Bell's book was mentioned. Also a great starting point is "Turbochargers" by Hugh MacInnes:

some of the book can be read at Google. Discussion of pressure maps on pg 17:

http://books.google.com/books?id=pewyJ3_F4XMC&printsec=frontcover&dq=hugh+macinnes+turbochargers

bamalama wrote:

Travis_K wrote: How cheap are you thinking? IMO, for a low budget turbo drag car you want a ford.

I agree. Gimme a roller 5.0L and a pair of HY35's and I'm set.

-10

(You drive an XR4Ti and you're giving out secrets about HY35s! Where am I going to get a spare if everyone starts putting 600HP through their 5.0L)

OK so +11, because this turbo + anything = cool, 32PSI is certainly neat in our 2.3L

Raze wrote:

bamalama wrote:

Travis_K wrote: How cheap are you thinking? IMO, for a low budget turbo drag car you want a ford.

I agree. Gimme a roller 5.0L and a pair of HY35's and I'm set.

-10 (You drive an XR4Ti and you're giving out secrets about HY35s! Where am I going to get a spare if everyone starts putting 600HP through their 5.0L) OK so +11, because this turbo + anything = cool, 32PSI is certainly neat in our 2.3L

I'm not worried about anyone taking me seriously. HY35's are safe. Until I get enough cash for one

32 PSI?? whut? umm yeah gotta check that one out. as I was thinking of a 5litre twin setup on a drag car next spring.......