Changing head gasket to lower comp

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F-BIRD'88
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Re: Changing head gasket to lower comp

Post by F-BIRD'88 »

You are not going to get what you want by changing head gaskets. You need to change the pistons.
A water-methanol injection system is a alternative.
You can use common blue winter formula windshield wash fluid that does not have soap or glycol in it.
Shake it. Its water and methanol.
Adding a ignition retard box that reduces timing at and near wot is another way to get by.
Reduce to about 30 deg at wot, heavy throttle , .as required. You want a vacuum advance dizzy. It will need to be modified to get the curve right.
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Re: Changing head gasket to lower comp

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I realize now the way the exchange rate and crazy taxes inflate your US bought parts works.
Take a look at these Brodix oval port race rites on Ebay. If you can swing the buy you will really upgrade the engine from both a workable compression level and better performance.
Hope you get your issue worked out. Best of Luck.
ebay listing #192692736442
The Older I Get, The Dumber I Get :wink:
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Re: Changing head gasket to lower comp

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I realize now the way the exchange rate and crazy taxes inflate your US bought parts works.
Take a look at these Brodix oval port race rites on Ebay. If you can swing the buy you will really upgrade the engine from both a workable compression level and better performance.
Hope you get your issue worked out. Best of Luck.
ebay listing #192692736442
The Older I Get, The Dumber I Get :wink:
F-BIRD'88
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Re: Changing head gasket to lower comp

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The "crazy taxes" (hst 13%) is what helps pay fir our crazy universal single payer health care here in Canada. A crazy idea eh!
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Re: Changing head gasket to lower comp

Post by F-BIRD'88 »

If you just change the heads the cr will be lower BUT still too high for pump gas. You will still need to then also change the pistons.
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Re: Changing head gasket to lower comp

Post by Baprace »

67 Nova, are the pistons a solid dome type, if yes then you could mill the dome off. JMO
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Re: Changing head gasket to lower comp

Post by 67 Nova »

Newold1 wrote: Thu Oct 18, 2018 4:41 pm I realize now the way the exchange rate and crazy taxes inflate your US bought parts works.
Take a look at these Brodix oval port race rites on Ebay. If you can swing the buy you will really upgrade the engine from both a workable compression level and better performance.
Hope you get your issue worked out. Best of Luck.
ebay listing #192692736442
Thanks that number doesn't come up. I've talked to a customer about buy my 215 heads for his shortblock, so heads could be in order.

I notice that my ported 215's outflow th RR 270 for 3-7 CFM thought the range from .200 up? Now I know flow isn't everything, but I just see what Mark Jones gets out of his OEM ovals is crazy!!!!! Just don't need to spend the $$$ on heads that are not be much better.
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Re: Changing head gasket to lower comp

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F-BIRD'88 wrote: Thu Oct 18, 2018 6:58 pm If you just change the heads the cr will be lower BUT still too high for pump gas. You will still need to then also change the pistons.
No. Changing of the heads will bring right down to easy pumpgas range. with .039" gasket I could be in the 10.3 to 1 range according to this calculator:

http://www.csgnetwork.com/compcalc.html
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Re: Changing head gasket to lower comp

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Baprace wrote: Thu Oct 18, 2018 9:22 pm 67 Nova, are the pistons a solid dome type, if yes then you could mill the dome off. JMO
Yes, I do believe the old L-2239n.030 are solid. BUT everything just went together.

Been looking at Chad Speier's Flotek 290's. I can get them for $17-$1800 US ready to bolt on with SRH stuff. There 121 cc chamber and that would bring comp right in line. I think IF the head change is need for the compression, THOSE will be the heads to get. Just gaskets will be $3-$400 alone and still not the best solution. Meth inject CDN $$ is about 1000.

Car is just getting ready to fire up. Going to chassis dyno with what I have and make a 1/4 mile runs on the dyno. Just get a baseline and doing research. Maybe a cam and gasket change can do it??? Not sure till all the cards are back on the table.
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Re: Changing head gasket to lower comp

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I know I'm talking to a customer about buying my 215's if they come for sale. I also told him about the Flotek 290's. I know he is off asking about them too where he can. He's native and not much for internet and car stuff.

I really think that the Flotek 290 heads from Chad Speier are the best bang-for-the-buck heads out there, BAR NONE. I just don't think enough people have tried them? Therefore not much info out there. BUT if the head change is needed, this is looking like the head I will use. Flow is good. It's NEW, not used and you can tailor them to your combo. Sorry I just don't see a down side with the Flotek's. Then you have the added feature of Chad being involved, that's a win-win in my books.
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Re: Changing head gasket to lower comp

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I could not agree more with your considering the Flo-tek 290's with an .051" gasket as your best choice. They flow well and are a very good head when set up right. As for a .039" gasket that might be a problem if your pistons are close to 0 on deck height as big block pistons rock in the bores and if the pistons are proud a few thou or at 0 that distance is probably too tight. I think new aluminum heads are your best choice so I hope you can make that work for you.
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Re: Changing head gasket to lower comp

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Newold1 wrote: Fri Oct 19, 2018 5:46 pm I could not agree more with your considering the Flo-tek 290's with an .051" gasket as your best choice. They flow well and are a very good head when set up right. As for a .039" gasket that might be a problem if your pistons are close to 0 on deck height as big block pistons rock in the bores and if the pistons are proud a few thou or at 0 that distance is probably too tight. I think new aluminum heads are your best choice so I hope you can make that work for you.
As this motor is together, I'm in the hole about .022" with these piston in this block. helps some. But with these being a CC piston and the Floteks are a OP head, I'm quite sure there should be no interference between piston and head.

I really think that IF I need to change around what I have, I will be going Flotek's. I have heard of some used AFR both 265 and 290's, and even used, people want MORE then a new set of Flotek's. That would put comp when I can use it, for the least amount of $$$.

Doing the the rest of the stuff for the car to update. New Dakota VHX dash, Underdash AC, power windows, cruise control, gear vender and stereo. Just ordering the dash aas AC this week. rest I have. Would like to look at a Sniper EFI as well. Just not sure do I do the Sniper then heads??? Guess the time out in spring will determine if the head swap is NEEDED. Because that will also dictate what Sniper unit to buy as well, Sniper, Super Sniper or Sniper 4500.
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Re: Changing head gasket to lower comp

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67 Nova wrote: Fri Oct 19, 2018 9:42 am I know I'm talking to a customer about buying my 215's if they come for sale. I also told him about the Flotek 290's. I know he is off asking about them too where he can. He's native and not much for internet and car stuff.

I really think that the Flotek 290 heads from * are the best bang-for-the-buck heads out there, BAR NONE. I just don't think enough people have tried them? Therefore not much info out there. BUT if the head change is needed, this is looking like the head I will use. Flow is good. It's NEW, not used and you can tailor them to your combo. Sorry I just don't see a down side with the Flotek's. Then you have the added feature of * being involved, that's a win-win in my books.
I have been using S P E I E R Racing Heads for several years. C h a d knows how to make POWER!!! GOOD CHOICE you will NOT regret it! Keep us informed!!!
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Re: Changing head gasket to lower comp

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redliner wrote: Tue Oct 23, 2018 10:24 amI have been using S P E I E R Racing Heads for several years. C h a d knows how to make POWER!!! GOOD CHOICE you will NOT regret it! Keep us informed!!!
I too have heard very good things about SPEIER and between that reputation and the $$$$ of those Flotek, I don't think I can go wrong for NEW heads that Chad goes through, puts HIS parts into and it just being a performance street DRIVER. AFR's are alot more $$$ US, then add the CND exchange, I don't feel it's worth it.

I always do well with what I have and make junk just flat out work. This car won't even have a rollbar, so really, it's just more drivability. Hell I would even look at cheaper heads, like Procomps, just with the Floteks I will be able to sleep better at night knowing that Chad is standing behind them, IF I need to go that route.
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