How drivable is a low compression NA setup? Tune?
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Reason I ask is I just finished my 8.7:1 347ci install. I've drove it twice (still untuned based off stock pcm) and it's really sluggish... for example if you try to put your foot 1/2 way into it at 2500 rpms it surges & basically laughs in your face and says "not going to happen." Anything over 2000rpms you can't gun it, though you can SLOWLY build rpms & speed. It seems to drive normal grandma shifting under 2000rpms.
How much will a tune fix this? I'm debating whether I should keep this motor or not since I don't have the funds to finish the turbo project, also I've either got to sell it or re-finance it. Wonder how much it'd cost to have a machine shop swap the dished pistons out?
How much will a tune fix this? I'm debating whether I should keep this motor or not since I don't have the funds to finish the turbo project, also I've either got to sell it or re-finance it. Wonder how much it'd cost to have a machine shop swap the dished pistons out?
Last edited by candlelit; 09-24-2008 at 02:56 PM.
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a tune will fix all of that. it should run smooth, not exhibit 'weirdness' at any TPS % or anything like that. granted it wont have the snot a 12:1 motor would, but you knew that going in and its a turbo project...thats the deal.
but yes, a tune will most def fix your woes. leave it together, finish the turbo someday!
but yes, a tune will most def fix your woes. leave it together, finish the turbo someday!
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well that's good ^ I may just refinance it then. though it really makes me, and others, sick they added the name Firehawk to the gxp car or whatever it's called.
I don't assume I should buy a tuning program and do it myself since I'm dealing with this low compression motor?
I don't assume I should buy a tuning program and do it myself since I'm dealing with this low compression motor?
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The lower compression, the more timing lead your motor will need. More timing at lower load settings will crispen things up a lot. Check your fuel too because you may be getting too much.
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2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
![](https://ls1tech.com/forums/signaturepics/sigpic210_1.gif)
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.