I need more compression!!

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doogievlg

doogievlg

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I have a 360 out of a 77 RV, It has a MP.484 cam, eddy 600 cfm carb, Torker intake, headers, 727 trans with a 3000 stall, B&M flexplate and i am running 3:55 gears...I am just craving more power and I have been told to do everything from get the heads done to get flat top pistons. I am on a tight budget so I have to decide which one to do and just wanted to know which would get me the most HP and compression gain for my money? Also I am by no means a engine builder so if anyone sees a prob with my set up do not be afriad to call me a idiot and tell me what needs to be done...I am shooting for 300-350 hp.
 
Swap to some magnum series heads if you can. Theyll outflow just about any LA series casting while the 63cc chambers will increase compression quite a bit. Youll need an Ebay intake, pushrods, and youve already got oil through lifters im sure. That stuff will probably cost $300-400 depending on how much magnum heads are where you live and where you get the odds and ends stuff. Aside from that you can get .028 thick headgaskets for $40 a set but that wont gain much without shaving the heads quite a bit and then your rocker geometry and intake mounting points change. Also with more compresion you need to make sure your ignition is doing a good enough job.

Also the magnum head bolts. I just reused the ones i got when i pulled the heads.
 
Ditch the Torker intake for good duel plane such as an Edelbrock Performer RPM. The Torker kills low and mid range power, and isn't worth anything up top. Cut the heads .040 or .050 to bump the compression up. Beware that Edelbrock intakes are notorious for needing the head flange cut down a like amount to compensate for head milling.
 
Just for some reference.....Your now approx. 8-8.25to1. With flat top/zero deck pistons, you'd be approx. 9.6to1. With Dustin's set up, comp would be right around 9.0to1. But should have a better breathing head. these numbers were arrived at using generally accepted stock averages:D.

P.S. a Eddy RPM intake would do wonders for your current set-up.
 
Sorry i should also mention that i was suggesting the thin headgaskets and head shaving if you kept the la series heads. Sorry for any confusion. How involved are you wanting to get to gain your comlression?
 
Magnum heads (esp. ported with bigger intake valves) and flat-top pistons... 10.5:1 compression your engine would scream!! But to properly put in new pistons you need to pretty much rebuild the engine or at least take it out of the car and apart.

Also get a bigger/better carb I think the one you have is holding back power
 
I agree with you "kid" on the carb....along with your other mods. Only reason i didn't mention it here is the smaller carb will tend to keep the mixture velocity up and that T340 need all the help it can get:).
 
I think I will just change the intake to an RPM and put a holley 650 or bigger on it and see what that does. Then once I get the funds Ill just tear the motor apart and do the heads and pistons together...then ill prob have to ditch the 8 1/4 though.
 
doogievlg said:
I think I will just change the intake to an RPM and put a holley 650 or bigger on it and see what that does. Then once I get the funds Ill just tear the motor apart and do the heads and pistons together...then ill prob have to ditch the 8 1/4 though.
Click to expand...

That sounds like the best way to go; you should notice a nice increase in torque with those mods
 
[QUOTE=doogievlg;..then ill prob have to ditch the 8 1/4 though.

I don't think so, they will take a pretty good beating.

For budget mods i think your on the right track for now. Even thou you have some gear and converter, your cam, intake and compression are not real torque friendly at this moment. Along with the intake swap, run a good timing curve with around 16-18* initial and around 36* total and i think you'll be impressed with the seat of the pants gains.
 
Where is the cam degreed? Is it the 108 LSA cam? If it is and you can advance it to 100 without valve to piston interference, do it. You'll get some low end grunt back. Not a lot, but, some. That might cost you a timing chain set and gaskets.

Right now it's probably a soggy loaf of bread under about 3000-3500

The intake and carb are a serious mismatch IMO. I'm not fond of the old torker340 if that's what you have, smelter material. :) The torker II isn't a bad piece. As mentioned you'd be better off with a RPM, Air Gap or LD340, even a Performer 318/360 would be better. Carb, look for a 600-750 holley, I'd prefer a 750.

Yes on the timing curve, 16-20 maybe even 22ish on initial with the low compression and get it all in by 2200-2500 with 36ish total. See where it's timed now. It could make a world of difference in how it runs in the current configuration.

That thing could run really hard with some minor tweaks and on pump gas all day long to boot.
 
I'm thinking that if you did a compression test, your cranking numbers would be in the 125-130lb range. More advance will make it alot more responsive in the low and mid range without suffering any top end rollover. If it was me, that's what i'd shoot for. You should still be able to run 89-91 octane considering your stock compression. Every combination acts different, but the more initial timing you can get in it without detonating the better. Experiment, experiment, experiment. You'll find what it likes.
 
I actually was looking at that thread before posting it and notice alot of guys running KB pistons and doing head work....I also noticed all the RPM intakes and holleys. The only reason I have the Torker on there is becuase thats what came on the motor...along with the carb. I put the motor in when I was 18 so I didnt have a ton of money. Now I am about to graduate college so I am dreaming about the increase in cash and considering I don't have a serious girlfriend or any real obligations then its all going into my dart.
 
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