Turbo sizing

Moderator: Mod Squad

64-5mustang
Registered User
Posts: 98
Joined: Sun Sep 20, 2015 9:43 pm

Turbo sizing

Post #1 by 64-5mustang » Sun Nov 04, 2018 9:27 pm

Hear we go with the age old question of how big to we want. I'm looking at installing a turbo for my 66 200 block 78 head ported and direct 2v will port and mod a exhaust manifold or make a header. C/r 8.5 Cam is still undecided max rpm would be 6000 more likely 5000. I really don't understand the sizing tables I've seen for turbo. I'm not looking to bost more than 5 pounds 10 if I'm gready. I'm mostly concern about about having the exhaust get choked by the turbo cause it's to small. Any advice I'm thankful for, thanks in advanced

pmuller9
Registered User
Posts: 2357
Joined: Tue Aug 06, 2013 12:33 am
Location: Columbus, Indiana

Re: Turbo sizing

Post #2 by pmuller9 » Sun Nov 04, 2018 11:31 pm

Ten lbs of boost is not greedy but a good minimum pressure to operate a turbo and most stock Ford sixes handle it just fine.

Secondly, do not overcam the engine.
For good low rpm response and power up to 5000 rpm keep the .050" duration under 210 degrees and use a wide Lobe Separation Angle at 112 degrees.
Clay Smiths smallest catalog cam is 214 degrees so look elsewhere.
I recommend the Schneider 256H cam with 204 degrees on a 112 LSA.
Good idle and low end responce. The ported head will carry the power past 5000 rpm.

A turbocharger with a 49mm compressor inducer diameter and a T3 open or T4 twin scroll turbine housing.

64-5mustang
Registered User
Posts: 98
Joined: Sun Sep 20, 2015 9:43 pm

Re: Turbo sizing

Post #3 by 64-5mustang » Mon Nov 05, 2018 9:42 pm

So your saying I should be looking at 10 psi as a normal working boost. A t 3 exhaust housing as i don't know how kind the making of a manifold will cooperate with the twin scroll t4 to be balanced nicely. And the intake side when you say 49mm compressor does that just mean the size of the turbine or the housing or both. I'm finding mix info.

Would this be a turbo to think about?.
https://www.jegs.com/i/Comp-Turbo-Techn ... 7/10002/-1


Also I do come across turbos from Subaru 2.5 would this be something to consider ?

pmuller9
Registered User
Posts: 2357
Joined: Tue Aug 06, 2013 12:33 am
Location: Columbus, Indiana

Re: Turbo sizing

Post #4 by pmuller9 » Tue Nov 06, 2018 4:28 pm

The Comp turbo you listed has a 49mm compressor inducer and will get the job done.

Yes 10 lbs is a good normal working pressure.
I don't know many that use less than that including those that started out saying only 5 lbs.

The compressor map is wider at 10 lbs (1.7 pressure ratio) meaning the turbo will operate more efficiently over a wider rpm range.

I believe the Subaru turbo has a 47mm compressor but it also has a small turbine housing that will choke a larger engine.

64-5mustang
Registered User
Posts: 98
Joined: Sun Sep 20, 2015 9:43 pm

Re: Turbo sizing

Post #5 by 64-5mustang » Wed Nov 07, 2018 7:29 pm

Thank you for the info. I now know enough to be dangerous.

thatblue_67stang
Registered User
Posts: 82
Joined: Fri Dec 22, 2017 8:25 pm
Contact:

Re: Turbo sizing

Post #6 by thatblue_67stang » Thu Nov 08, 2018 4:33 pm

As someone who said i was staying with 5psi i will not be. 5psi is amazingly fun and would be more than happy with leaving it there but if the engine can handle 10 um going to send it haha. ive had it at 10psi before but my accelorator shaft on my carb is leaking fuel bc the boost is forcing it out. once thats sealed i will be going to 10psi
Brayton
1967 Ford Mustang Coupe
200 Inline 6 Turbo Charged

Image Image

pmuller9
Registered User
Posts: 2357
Joined: Tue Aug 06, 2013 12:33 am
Location: Columbus, Indiana

Re: Turbo sizing

Post #7 by pmuller9 » Thu Nov 08, 2018 9:18 pm

Just make sure that the timing is being retarded as manifold pressure increases and the air fuel ratio is richened.

Who is online

Users browsing this forum: No registered users and 6 guests