alright guys so heres the deal. im out to try and set some records. around the colorado/wyoming area. maybe even the US if i get a lil crazy. i want to push the STOCK bottom end to its max power making potential limit, and have a fully built top end. the only problem im running into is head work. me and my shop got some ideas so far for the port and polish i want done, but that is a secret until its finished . but i was thinking of when were redoing the valve grind to only do a 3 angle. i have researched and i honestly think a 5 angle is a little too much for a boosted application. unless i was doing high compression and low boost. but as far as valves, seals, cams, guides, springs and retainers go, i need the EXPERIENCED peoples help. i need you guys to tell me about some of your experiences with head stuff and how well it worked and how long it lasted for you. personally, i am a brian crower cam guy, so im thinking im just going to stick with them for cams. great powerbands. let me have your insight and lets see what kind of builds youve done. also, if you have any pics of your top end after it getting built lets see it . thanks by the way, this is a 6 bolt motor. and im going to be running either a gt40r or a gt42r. i have both at my disposal just gotta bolt em up.

I think I saw 650hp on here on a stock longblock. If the guy you're having do your valve job doesn't know what will flow the best, he may not be the one to have do it.

Make sure he has a flow bench to test his work - if done improperly a port and polish can hurt your power output.

im just trying to get real life experiences on head parts. seeing as how that is the weak link of a 4g63. ive heard of people getting up to 750 on a stock bottom end, but yet actually seen it. this is why im doing this build. to show people what our motor can withstand

bc's lick buttholes if you are really trying to get something outta your head. go buy some kelford cams.... i would recommend a 272 setup. i know i will get flamed by BC lovers.. but cheap ppl just dont ealize that cheap shyt don't cut it. you want some real gains get a good cam. and if your man doing the headwork on your car doesn't know what is best for what you are looking for, have someone that really knows what they are doing with these motors do the work...

I have BC272's, but yeah I'd go with the Kelfords if you wanna get some serious power.



Why do you say the head is the weak link of the 4g63?

btw, there is a vid on myspace.. someone getting something like 1000hp on a stock bottom end or something like that. crazy shat man... good luck with your goal

not sure if it is a stock bottom end, but it is on a pump gas... !!!!!

YouTube - eclipse 1000hp video

^^^No. NOT stock bottem end. That is the Gasoline Record Car. Not pumpgas either.

No, the stock block (rods/pistons) usually are not good for over 550whp. There's a few instances where it's gone up to 600whp. . . But it's you're loss. The record is jsut over 600whp with a dynojet and another car has done about the same with trapspeed and known weight to calculate HP (more reliable to look at trapspeed IMHO).

I do not think the head is the weak link. From my experience with this motor and many others, the heads flow very well. The piston design isn't the best in my opinion, but doesn't seam to hold it back too much. VS a honda? The 4g63 starts off with terrible compression and pathetic cams with a mediocre intake manifold. There's alot 'holding the head back'.

If you want big power, you might as well just build the engine. You'll put this into the head, and when the engine blows the head will have bent valves at the very least. If you're looking for 500-550hp go for it stock, otherwise you're really pressing your luck. Build it right and build it once.

i have never had a bottom end give out on me. it has always been the top end. valves floating, bending, etc. im not trying to rub any thing in, but i have disposable money. so a ####ed head isnt going to hurt anything. and i have never heard of kelfords. and yes, the intake manifold is a weak design. rough as shit, small ports, we all know the weak points. the other thing i dnt know about is intake manifolds. i have never experimented with intake manifolds. just port matching mine myself. what are your opinions on intake manifolds?

well if you have never heard of kelford's then look into em.. ### if you are thinking bc's then you don't know what real world numbers vs money really factors in... bc's are shyt... that is not just my opinion...... as far as the head. get a built head. under 1500... and throw in the kelfords and you will be set for any goal your trying to achieve. make sure you get dual springs... and the proper valve guides... the head produces great numbers and flows VERY well. even into the 7-800hp range proven by twicks... in his car (stroker)...good luck with your build. if you are really looking to prove something do your research before you start!

dsm-onster thanks for the correction and for clearing that up. just wanted to give an idea what a 4g63 can do... maybe should take down the vid?

im was thinking about doing the same just building the head and keeping the stock bottom end but as for teh valve job the 3 angle or 5 angle wont give you power it will just help the valve seat properly. a 3 angle valve job will work just fine, but i would say build the bottom end too, or if you keep it stock at least get some race bearings and arp main studs rod bolts, head studs, and rehone the bottom end just freshen her up

I think my Stage 6 head (full race port claim) from SBR will be a good head, and I've got Crower 280 cams in it with o/s valves, an 80mm TB, and custom SMIM (jmf clone)... We'll see how she does I guess.

crower 280's or bc 280's? just wondering.

90rslaser said:

i have never had a bottom end give out on me. it has always been the top end. valves floating, bending, etc. im not trying to rub any thing in, but i have disposable money. so a ####ed head isnt going to hurt anything. and i have never heard of kelfords. and yes, the intake manifold is a weak design. rough as shit, small ports, we all know the weak points. the other thing i dnt know about is intake manifolds. i have never experimented with intake manifolds. just port matching mine myself. what are your opinions on intake manifolds?

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I've cracked 8 pistons and bent 3 rods. All with a 60-1 (580whp turbo), and the h1c (500whp turbo). Yes, I could be a retarded tuner . These were all stock 6-bolt builds; 6bolt blocks are the most durable. They didn't detonate. If they did it was under 4 counts. But that small amount of knock sent metal flying everywhere. I'm not negating the durability and potential of the 4g63 block. It's one hell of a 4 cylinder, but I've got eagle rods and wiseco pistons, and along with my tuning experience that I've earned the hard way, I'll not worry about my bottom end for my 600whp build.

No one has gone up to 750whp with the stock rods and/or pistons.

BTW i would never want to port anything on intake side of the head by hand any variance in airflow between ports will cause issues when tunning. say one port flows 3.5% more air than another port, well that cylinder needs 3.5% more fuel to maintain the same AFR.

Congrats on your stock bottom end goal but if you don't mind me asking how much hp are you currently making?

i hit the 450 mark with just a frshened up head, arp studs, cometic mls gasket, watermeth, intercooler spray, kinetic front mount, pte 750 injectors, whalbro 255, a ported 2g exhaust manifold, and buschur racing ported and clipped dual bb 20g, and a kinetic 38mm wg. but that was only at 22psi i believe. but believe me, ive had many vehicles in the 5000-700hp range. i am currently finishing touches on my 86' camaro rs. built 383 stroker. but as far as intake manifold porting went, we took all the safety precautions to make sure it flowed perfectly fine. i have the flow charts somewhere that ill post up. but like i said i am just trying to get peoples experiences with parts. and i will NEVER buy from slowboy again.

correct me, that was supposed to say 500-700. not five thousand . and yes. the bottom end is a fresh stock rebuild.

90rslaser said:

i will NEVER buy from slowboy again.

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I think plenty of people are in the same boat with you buddy, myself included!

90rslaser said:

. . .and buschur racing ported and clipped dual bb 20g, and a kinetic 38mm wg. but that was only at 22psi i believe. but believe me, ive had many vehicles in the 5000-700hp range. . .

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Is that real?

Clipped too?

we all know the boost we run. We don't need to believe it.

yes that is real. with a little modification here and there. . when i get my computer fixed i will start posting up pics and shit of my tear down and what not

What turbine wheel do you have?

You do know there is a 250 to 300whp difference in potential between the two turbos 'at your disposal', right?

im not sure what wheel is on it but i can find out though. and yeah, ive heard there can be big differences between the 2 turbos. thats y im gnna try both and see which one i like best.

need2boostpsi said:

BTW i would never want to port anything on intake side of the head by hand any variance in airflow between ports will cause issues when tunning. say one port flows 3.5% more air than another port, well that cylinder needs 3.5% more fuel to maintain the same AFR.

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+1 the only way to tell this on a car while its runnig is if you have a wideband for each cylinder. the only thing i would ever port without a flowbench is exhaust stuff ports, manifolds, turbos, o2 housings