boost pressure?
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Topic: boost pressure?
Posted By: Toscani NE SD
Subject: boost pressure?
Date Posted: 14 Mar 2015 at 10:41pm
| is there a formula for HP going by boost pressure?on my xt 190 III,it has a 30lb boost gauge and it will peg that about 3/4 down the track and a nice flame out the pipe |
Replies:
Posted By: DrAllis
Date Posted: 15 Mar 2015 at 9:56am
| I know in one twin-spin 301 A-C Puller, 100 psi intake boost relates to near 1000 flywheel HP on the dyno. By that math, 30 psi would be 300 HP. This is only a theoretical calculation and your results may be different. Seems like a 7020 tractor was around 18-20 psi making 120 PTO HP which would be 145 flywheel HP. |
Posted By: Beirnesy
Date Posted: 15 Mar 2015 at 4:36pm
I may be asking a stupid question, Does your xt still have PTO shaft? if yes, dyno it and let us know the hp !! ------------- 1969 220,1967 190DXT,1968 190DXT, LGT's 710,,716 |
Toscani NE SD wrote:Posted By: wi50
Date Posted: 15 Mar 2015 at 7:05pm
|
Here's the quick and dirty of it. Your engine doubles for every atmosphere of boost. So if you have 80 HP naturally aspirated, with 15 psi you have 160, with 30 psi you should see about 240 HP. Now there's thermal inefficiency because you heat the intake air with a turbo and some other factors to subtract. Then come changes in can and cylinder head, fuel system etc. So the engine pushing 7 atmospheres boost (approx 100psi) making 1000 HP has had to have some other modifications of course, but is limited by its cylinder head. Another engine with a better cylinder head pushing 100 psi may make 1300 a d yet another of that size could make 1800. The 301 heads just aren't great for making big HP, but the cylinders are small, a d they like rpm. ------------- "see what happens when you have no practical experience doing something...... you end up playing with calculators and looking stupid on the internet" |
Posted By: Peterson
Date Posted: 15 Mar 2015 at 7:30pm
|
More boost does not mean more horse power. Boost is just a restriction on the intake path. ------------- 7095-685I at 255hp, 8070-225HP,8050-210Hp,8030 with 155HP,220 with 670T engine with A-pump, 7580, 185 with 140HP, 2-6080's,6070, S4 D17,wd45,CA,st34 agco, S1 D17 with 3500MK2 |