11.1 + comp ?

[68chargerboy]

i am planning on being over 11.1 Comp. with my engine.  so i was wondering if this amount of compression is streetable with pump gas.  i was also wondering what the highest i can get my compresion to be able to drive on pump gas.  thanks alot




                                         Zach

[firefighter3931]

i am planning on being over 11.1 Comp. with my engine.  so i was wondering if this amount of compression is streetable with pump gas. 

Inmo that is too much compression to run safely on the street. Ideally, you want a 10.5:1 tight quench build for best performance and detonation resistance. Here's a good thread for you to read through :

http://www.dodgecharger.com/forum/index.php/topic,782.0.html


Ron

[8WHEELER]

I agree for the most part. But I would not go over 10.0 My wife's all stock ''except for a mild comp cam'' 68
Charger RT 440 Magnum, runs great for the most part on the street. But head up a somewhat steep hill and
lean on it a little and even on premium gas I can't get it to not ping    I have tried everything.

Dan

[firefighter3931]

I agree for the most part. But I would not go over 10.0 My wife's all stock ''except for a mild comp cam'' 68
Charger RT 440 Magnum, runs great for the most part on the street. But head up a somewhat steep hill and
lean on it a little and even on premium gas I can't get it to not ping    I have tried everything.

Dan

Dan, just to clarify, he is asking about an aluminum headed stroker build allthough there is no mention of that in this thread.

http://www.dodgecharger.com/forum/index.php/topic,16774.0.html

If it was an iron head build i would agree with you 100%


Ron

[Chryco Psycho]

it depends a lot on how you drive , I had a 440 at 11.2;1  on pump gas [Sunoco Gold 94] but it had a MP 590 cam 312* duration to bleed off cylinder pressure & a clutch & I never put load on the engine below 2500 RPM & would dump the clutch above 3000 if I wanted to leave hard , it never pinged & lived 9 seaasons being shifted at 7200 rpm but for most poeple 10:1 is max 

[8WHEELER]

Yes I could run my 11.5 TRW's and my 915 heads on pump 92 premium gas 5 or 6yrs back, infact I could
take it down to the track that way. But not anymore, the gas today is not what it was even 5yrs ago.

OK, with aluminum headeds you do have some play, thanks for the heads up Ron  I don't spend
anytime in the performance section, infact I have sold or traded all my speed parts pretty much, just have a
good amount of the less expensive braided line still here, and a couple of those blue 3/8 dual feed setups,
one has never had a wrench on it yet, and other small stuff, time for ebay posting 

Dan

[tecmopar]

It would be a little rough to be streetable on pump gas, as Ron said you may want to go down a little or spend 6-7.00 bucks a gallon for gas.

Chryco, if your dumping the clutch at 300 it must bog real bad, ha ha.

[firefighter3931]

it depends a lot on how you drive , I had a 440 at 11.2;1  on pump gas [Sunoco Gold 94] but it had a MP 590 cam 312* duration to bleed off cylinder pressure & a clutch & I never put load on the engine below 2500 RPM & would dump the clutch above 300 if I wanted to leave hard , it never pinged & lived 9 seaasons being shifted at 7200 rpm but for most poeple 10:1 is max 

I can see that type of combo working ; light car, low cylinder pressure, no load etc...

It's unfortuanate that all the relevant information isn't posted. From reading the other posts Zach has made, this engine is destined for a heavy car with 3.55 gears and 3000 stall....more of a cruiser type build. Under those conditions the engine willl see lots of heavy load and be susceptible to detonation. With the crummy gas we have today, it's imperative to get the build right or risk ruining the engine with detonation. That being said, 10.5:1 & tight quench with aluminum heads is pretty safe. Pushing the pump gas envelope just isn't worth it. 


Ron

[68chargerboy]

i often buy gallon cans of nitro methane as an octane booster. so if i were to put some of this in my tank will i be able to run higher comp.  i also use a lead addative.  thanks alot


                    Zach

[Chryco Psycho]

dumping the clutch at 300 would be an issue alright !!!