AE92Nova Posted June 5, 2013 Report Share Posted June 5, 2013 Hey guys, I have a 4AFC I'm Working to try and get 4AGE Power out of it... So far i have Dropped a Twin Barrel Weber Carby with a RamFlo, Along with a set of extractors and a 2" cat back exhaust, 2" muffler, Free-flow Cat. Installed a Heavy Duty Cluth, Along with a new Timing Belt and a GT40 Coil.. I plan to Reco it along with adding Heavy Duty Value Springs, and a Stage 3 Cam RPM Redline is about 8-9K going to try for 11K, and Plan on keeping it a low Combustion Engine for some Boost Any thoughts or Advice is apprecated , Apart from getting a 4AGE... Quote Link to comment Share on other sites More sharing options...
luk3333 Posted June 5, 2013 Report Share Posted June 5, 2013 I think if you want near 4AGE power with an F head and carburettor, you will need high compression. 4AGE's have the power they have because they have a good flowing head, and rev up nicely due to their bore to stroke ratio, and obviously have EFI. Your 4AFC's bore and stroke is the same, the head is different and so is the fuel system. So you will have to either do head work to increase flow on the F head or swap to a G head. A G head would have to be cheaper and be better value. You want to keep the carburettor, but you may have to swap to side draughts for the extra flow at high rpm. The higher rpm the engine spins, the faster the gases moves, the more important flow becomes. If you take your 4AFC and put a G head on, a set of properly tuned side draughts, and bump up the compression a bit by shaving the head you should have a similar power output. I would think a mild 4- 6k or perhaps a 5 -7k optimum cam would be more useful to you. Duration affects where the power is, lift affects the flow characteristics(more lift, more flow), and the spring rates affect how high you can rev your engine. A big cam will help, but if the cam is optimal for 8K onwards then it will drive like crap at low rpm. How often are you in the 8k and beyond rev range? You shouldn't need to go past the factory redline to make 4AGE equivalent power. Quote Link to comment Share on other sites More sharing options...
carbonboy Posted June 5, 2013 Report Share Posted June 5, 2013 Hey guys, I have a 4AFC I'm Working to try and get 4AGE Power out of it... Installed a Heavy Duty Cluth, Along with a new Timing Belt and a GT40 Coil.. RPM Redline is about 8-9K going to try for 11K, and Plan on keeping it a low Combustion Engine for some Boost Any thoughts or Advice is apprecated , Apart from getting a 4AGE... I highly suggest you take a look at what it takes & more importantly, what it costs to get a 4AGE to spin RELIABLY to those kind of RPM & reconsider your thinking. Don't mean to be rude, but I think you're dreaming a little. Got the feeling this topic has been covered before too :hmm: A boosted 4AFC would be interesting, would probably make 4AGE power, but would cost more to do as all the fabrication work would add up. Lower compression is what you'd need for that, which seems to be the opposite of what you intend to originally build. Quote Link to comment Share on other sites More sharing options...
Hiro Protagonist Posted June 5, 2013 Report Share Posted June 5, 2013 Plan on keeping it a low Combustion Engine for some Boost "Keeping" it low compression (I assume you mean compression)? 4AFCs are already 9.5:1, hardly "low" compression Quote Link to comment Share on other sites More sharing options...
ke70dave Posted June 5, 2013 Report Share Posted June 5, 2013 (edited) How does the 4afc go with all those mods? you don't hear of many people playing around with the 4afc, i bet it goes alright though! I think you need to decide if you are going to go boost or not. There is nothing more fun than high compression + boost, not too high but 9.5:1 would make for some fun. But if you decide to keep it N/A, your going to need higher compression and a big cam to get the 4age power, but you may find it a dog to drive on the street.... Theres nothing wrong with playing around like this, even though the 4age is probably the better economical option, you just have to make sure that any mods you do are cheap so you don't start overcapitilising on a 4afc! If you start paying 1000's of dollars for camshafts and head work, then its a bit of a waste of money i think. But negating costs It would be a fun project though! Considered scrapping the carby and getting the 4afe efi system on there? Edited June 5, 2013 by ke70dave Quote Link to comment Share on other sites More sharing options...
GJM85 Posted June 6, 2013 Report Share Posted June 6, 2013 (edited) The 4afc head is designed to produce maximum torque at low rpm, hence the narrow valve angle. We call this economy because your not revving out with your boot on the floor. Power figures may not match a 4ag but with the right mods torque could be ridiculous, making you faster than a 4ag anyhow. Power sells cars, torque wins races. Edited June 6, 2013 by GJM85 1 Quote Link to comment Share on other sites More sharing options...
rthy Posted June 6, 2013 Report Share Posted June 6, 2013 Power sells cars, torque wins races. 7afe 1 Quote Link to comment Share on other sites More sharing options...
Nitskees Posted June 20, 2013 Report Share Posted June 20, 2013 Cool little topic :) just recently got my daily on the dyno at work for a power run :) made 90.4hp atfw's from a stock 4afe with extractors/exhaust and CAI, no power steer or ac anymore though :) would bee interesting if someone put abit of effort into one of these :) Quote Link to comment Share on other sites More sharing options...
CorollaMansta Posted October 3, 2013 Report Share Posted October 3, 2013 I decided to keep my 89' 4A-FC and i got good plans for it just to mess about! Got 2'' free flow from catelic converter to tail lights, will get the rest later got 32/36 weber on the way got a extra 4A-FC on the way to recon and bolt on the upgrades the just drop it all in (looking if i can get cams for the original head otherwise i see people are putting the G heads on and then bolting the carby on the G head? does that sound right?) so ill do that. looking for new bumpers or restoring current got 17'' ROH SHIFT-R on the way wil get repainted basicly wanting mid range torque and a good clean car, not into high RPM racing 5mm from the ground, will just be my other girlfriend everyday cruiser Anyone got any other ideas? would like some input, cheers guys Quote Link to comment Share on other sites More sharing options...
trentae92 Posted November 16, 2013 Report Share Posted November 16, 2013 4afc with 2nd gen 4afe head efi bump up compression hd valve springs Quote Link to comment Share on other sites More sharing options...
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