Higher compression engines with low boost ...
Or lower compression and more boost ..... ?
Or lower compression and more boost ..... ?
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lower compression with more boost, if u can tune it properly. Boost with high compression you start running into major detonation problems, and have to run more octane=tons more for fuel. (by high compression i mean 10+) (lower comp with higher boost id stick around 8.5) But it's just my opinion.You may or may not know 10 times what i do.
ASE Master certified. Just means I can take tests. GM ASEP Graduate.
95' Z26, ported/cammed 3400/3500, OBD2, 282, T3T4. Boxes almost all empty.. -
Depends probably on the end goal. But I have wondered too. I'd say for a street driven application, low boost (10psi and under), high compression (meaning stock N/A) since you'll have more power and response when the turbo is not spooled up yet.sigpic
New 2010 project (click image)
1994 3100 BERETTA. 200,000+ miles
16.0 1/4 mile when stock. Now ???
Original L82 Longblock with LA1, LX9, LX5 parts
Manifold-back 2.5" SS Mandrel Exhaust. Hardware is SS too.
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Yeah, it depends on what you really want. If you don't mind some slight turbo lag while it's spooling to 10+ psi, then lower compression. But if you want power off the line (if you're not power braking/holding in the clutch) then stock compression with lower than 10 psi of boost. "idealy" you can put 10 psi to any engine, according to a few boost books, but you have be able to tune it, adjust your fuel pressure, and add more than what you can stock. And if you look in the "boost" section of this forum, there are other things you can do as well to help prevention of detonation (detonation is what basically blows up your engine). And most of the time, it starts to detonate at your higher rpms/boost, and by that time it's too late.You may or may not know 10 times what i do.
ASE Master certified. Just means I can take tests. GM ASEP Graduate.
95' Z26, ported/cammed 3400/3500, OBD2, 282, T3T4. Boxes almost all empty..Comment
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I have ran engines both way's and I prefer the high static comp, with the low boost, like a supercharger on an old sbc/ bbc.
The low end power issues below boost is what I hate....
I like a rich mix, about 15.1 for tuning for boost, some say 12.5/ 1 af is ideal...
Seems lean to me...Last edited by powerdoctor; 04-15-2008, 09:21 AM.Comment
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How the hell do you do this for a living when you don't even know 12.5:1 is rich and 15:1 is lean?Originally posted by powerdoctor View PostBen
60DegreeV6.com
WOT-Tech.comComment
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12.5 :1 is richer than 15:1 FYI. an engine running an AFR of 15:1 under boost is gonna probably burn up, or at least not run well, and very hot94 Grand Prix
3400- NX 75 shot, Cammotion cam, S&S headers, and a few more toysComment
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sorry ben, you posted the same time i did94 Grand Prix
3400- NX 75 shot, Cammotion cam, S&S headers, and a few more toysComment
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I'm chasing a 1.5 yo around (my son)
I watch my boys every morning while the wife works...
sorry about the mess up , you know what I mean....
Later haters......Comment
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Originally posted by powerdoctor View Post
That's one of the best cover ups ive heard
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Lean is meanYou may or may not know 10 times what i do.
ASE Master certified. Just means I can take tests. GM ASEP Graduate.
95' Z26, ported/cammed 3400/3500, OBD2, 282, T3T4. Boxes almost all empty..Comment
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Then what AFR do you prefer?Your local OBDII moderator
2000 Grand Am GT w/ WOT partsComment
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I still prefer 14.7-1, but that's just me. Lean is mean, but replacing engines is worse .
You may or may not know 10 times what i do.
ASE Master certified. Just means I can take tests. GM ASEP Graduate.
95' Z26, ported/cammed 3400/3500, OBD2, 282, T3T4. Boxes almost all empty..Comment
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14.7 for N/A cruising, but when you go WOT even on a N/A engine, you need richer.sigpic New 2010 project (click image)
1994 3100 BERETTA. 200,000+ miles
16.0 1/4 mile when stock. Now ???
Original L82 Longblock with LA1, LX9, LX5 parts
Manifold-back 2.5" SS Mandrel Exhaust. Hardware is SS too.
Comment
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I have limited understanding of boost, but I was planning to keep the stock compression and run ≤10psi on my next build.'98 Volvo V90 - Ford 5.0 swap in progress
'96 LR Range Rover 4.6 HSE - suspiciously reliable
'92 Volvo 740 Wagon - former parts car, now daily-driver beater
'71 Opel Kadett Wagon - 1.9L CIH w/ Weber DGV 32/36, in bitsComment
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!!!!! BOSCH PLUGS RULE !!!!!
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