Turbo Kit Discussion Thread

[shawnc16]

Every kit produced out there is 2.5". I have done PLENTY of homework and have been into the turbo LS1 game for 5 years now..... 2.5" IS the correct size for the crossover and 3" IS the correct size for the downpipe for this kit and people wanting to boost their LS1 from stock form and up into forged applications! If you want to build a kit with a 3" crossover then be my guess but the only thing that extra size is going to do is kill your spool time! I know what's happening here sir

Where did I go out saying that a 3" crossover needs to be used? I didnt say that anywhere, infact Im saying that your perfect sized 2.5" crossover is too large. I know I just busted your balls on internet forum reading but, heres some actual data for you. Read up before you go stealing peoples money.

http://www.ls1tech.com/forums/forced...old-build.html

[shawnc16]

This is actual data based off calculations. 2000+ HP was made with a 2.5" crossover. Your telling people that 2.5" crossover is good to 1000HP?

On a 370" & 20# of boost & 7200 should make 1100hp....
Most factory 205/215 castings have a exhaust port that measures 1.400 x 1.600
Headers:
1.50" = 276FPS
1.62" = 235FPS
1.75" = 203FPS

Crossover:
2.00 = 622FPS
2.25 = 491FPS
2.50 = 398FPS

Merge
2.50" = 796FPS
2.75" = 658FPS
3.00" = 553FPS

Now I just need some turbo measurements for a T4, The T4 looks to have an inlet with about 5.6-5.7" sq/in of area

Turbo inlet @ 5.65" = 700FPS

Going with a larger tube between the header and turbo will increase the area which will require more time to fill and generate the drive pressure for the turbine. You can go too small....


Now reading this data. It shows that 2.50" piping is actually the slowest flowing piping out of the three sizes used. What that means to me is lack of effieciency on an engine making 1100 HP. Is that what you read from this too?

[Superman09]

Where did I go out saying that a 3" crossover needs to be used? I didnt say that anywhere, infact Im saying that your perfect sized 2.5" crossover is too large. I know I just busted your balls on internet forum reading but, heres some actual data for you. Read up before you go stealing peoples money.

http://www.ls1tech.com/forums/forced...old-build.html

Stealing people's money? I have ran 2.5" on BOTH of my previous kits. I have ran 2.5" on a stock engine and had INSTANT spool. I really appreciate all your nice help in this thread. In the future if you want to just hop in and try to cut me down, take it to PMs

[Superman09]

This is actual data based off calculations. 2000+ HP was made with a 2.5" crossover. Your telling people that 2.5" crossover is good to 1000HP?

On a 370" & 20# of boost & 7200 should make 1100hp....
Most factory 205/215 castings have a exhaust port that measures 1.400 x 1.600
Headers:
1.50" = 276cfm
1.62" = 235cfm
1.75" = 203cfm

Crossover:
2.00 = 622cfm
2.25 = 491cfm
2.50 = 398cfm

Merge
2.50" = 796cfm
2.75" = 658cfm
3.00" = 553cfm

Now I just need some turbo measurements for a T4, The T4 looks to have an inlet with about 5.6-5.7" sq/in of area

Turbo inlet @ 5.65" = 700cfm

Going with a larger tube between the header and turbo will increase the area which will require more time to fill and generate the drive pressure for the turbine. You can go too small....

Good, take that and go build one for your car Thanks

[JoeliusZ28]

I know I just busted your balls on internet forum reading but, heres some actual data for you. Read up before you go stealing peoples money.

You might want to search his screenname on LS1tech and see just how active he has been in the forced induction section. Your calculations may be correct, but stealing peoples money? I don't think so, his last 2 twin turbo setups performed well.

[shawnc16]

Look, Im not looking to bash you here. I'm bringing you valid data. I'm just looking for your data. Stealing peoples money may be a little harsh. I just want to see your data. As a consumer, I expect quality with data to back it. I'll jump out of the thread if thats what you want me to do.

[Superman09]

Look, Im not looking to bash you here. I'm bringing you valid data. I'm just looking for your data. Stealing peoples money may be a little harsh. I just want to see your data. As a consumer, I expect quality with data to back it. I'll jump out of the thread if thats what you want me to do.

I do not have data. I do not have a math sheet to show you. I can tell you from the 5 years I have been in this game, I have seen about 90-95% of the front mount builds done with a 2.5" crossover with great results from a range of stock motors to big built motors. I feel the results justify why 2.5" was used. If people see 2.5" used time and time again in great power producing set-ups I think they will want that in their set-up. Surely other diameter piping could be beneficial in certain circumstances but the 2.5" Crossover is proven time and time again in MULTIPLE applications. In fact if I went with anything other than 2.5" crossover, many would be skeptical and I would probably not attract as many customers being the 2.5" is so proven. I hope this helps and clears up all of your issues.

[shawnc16]

I do not have data. I do not have a math sheet to show you. I can tell you from the 5 years I have been in this game, I have seen about 90-95% of the front mount builds done with a 2.5" crossover with great results from a range of stock motors to big built motors. I feel the results justify why 2.5" was used. If people see 2.5" used time and time again in great power producing set-ups I think they will want that in their set-up. Surely other diameter piping could be beneficial in certain circumstances but the 2.5" Crossover is proven time and time again in MULTIPLE applications. In fact if I went with anything other than 2.5" crossover, many would be skeptical and I would probably not attract as many customers being the 2.5" is so proven. I hope this helps and clears up all of your issues.

So offering a kit with quicker spooing, better efficiency (more hp/tq) with better heat retention, smaller (lighter) piping and proven data to back why the kit is better than a cookie cutter kit is not what you're going for? I understand that MOST people use a lot of things. Take one thing and run with it. Is it the most efficient design? No, will it work? Absolutely.

If you'd like to find more posts by Phil99Vette, look him up on yellowbullet as well 95mmRenegade. He's running a 2.5" crossover on an engine making 2300 HP. If anything maybe this may help you out. Not all criticsm should be taken as bashing or personal attacks.

[Superman09]

So offering a kit with quicker spooing, better efficiency (more hp/tq) with better heat retention, smaller (lighter) piping and proven data to back why the kit is better than a cookie cutter kit is not what you're going for? I understand that MOST people use a lot of things. Take one thing and run with it. Is it the most efficient design? No, will it work? Absolutely.

If you'd like to find more posts by Phil99Vette, look him up on yellowbullet as well 95mmRenegade. He's running a 2.5" crossover on an engine making 2300 HP. If anything maybe this may help you out. Not all criticsm should be taken as bashing or personal attacks.

Well what I offer to you then is to take the data, test yourself and market a kit.
I am making a kit with a proven design. There are so many variables in a kit, and you are pinpointing 1 single aspect of the kit. If you are nitpicky this much then this kit is not for you. You need to go to a shop and have them build you one to spec for $12 grand and I will sell mine for a quarter of that. We might spool a couple RPM's behind you but will have $9+ grand to spend to get that back.
I am building an AWESOME budget turbo kit here. I am not building one off kits per customers spec'd. The 2.5" Crossover is perfect for all areas covered so that is what I am going with. Thanks

[shawnc16]

Nah, building my own, spec'd by myself. I won't go into the rest of it. Actually the cold side looks really good. Hope it works out for you.

[Superman09]

Nah, building my own, spec'd by myself. I won't go into the rest of it. Actually the cold side looks really good. Hope it works out for you.

thanks, I know this kit will work phenomenally!

[c0ncEpT]

Why not use a 1" crossover. I'm sure the exhaust velocity would be through the roof.

A TC 76 will support 800+ RWHP and make full boost well before 3500RPM in a front mount setup regardless of the crossover size so what does it even matter? Why would you even want the power to come on sooner than that?

[Superman09]

Why not use a 1" crossover. I'm sure the exhaust velocity would be through the roof.

A TC 76 will support 800+ RWHP and make full boost well before 3500RPM in a front mount setup regardless of the crossover size so what does it even matter? Why would you even want the power to come on sooner than that?

I believe they say, "boost for the action, lag for the traction"

[shawnc16]

Why not use a 1" crossover. I'm sure the exhaust velocity would be through the roof.

A TC 76 will support 800+ RWHP and make full boost well before 3500RPM in a front mount setup regardless of the crossover size so what does it even matter? Why would you even want the power to come on sooner than that?

You can go too small just like going too large. Do you throw the biggest cam and stall on the shelf on a turbo car? No, it doesn't work. Do you stick a cam in that's smaller than stock and a stall lower than stock? No.
I understand the outlet of a truck manifold is 2.5"but those exhaust manifolds are build for a naturally aspirated engine. The 2.5" will work. Especially when spooling a small turbo like the T76. Throw a real turbo on it and see what happens. Also, as shown in the data, the manifolds/headers have the slowest airspeed out of all the other parts of the system so its easier to get away with a less efficient design.

You want to keep as much heat and airspeed in the pre-turbo exhaust as possible. I guess I like performance a little more than MOST people..

[shawnc16]

A 3" downpipe and 38mm wastegate is good for 800 whp? Show me