I will be slowly building up an A1

[FyreDaug]

Next week I will be getting a head from a wrecker. And I will do the pnp work myself. It will be ported a little more than what would typically be done, I have a theory that I will end up spending some money on for R&D for myself and I'd like the help of the 3geez members to guide me along.

To match up to the head I may or may not be getting a header that was offered to me via PM. A pacesetter :| and running 2.25" all the way back, no restrictions. Huge long resonators and straight through muffs only on the exhaust. Hoping not too much :rice:, but I'll do what I can after the fact.

For an intake manifold, me and a friend are doing some research I dont wanna share right now (because its a "stupid idea" but a couple mech's Ive talked to said it could very well be worth it). Ofcourse port matched to the head.

The valve train wont be too drastic. It will be rebuilt, but Im not going to be going for a super high revving engine. 6.5k limit is fine with me for my theory anyways. The head will be decked and a 3 angle valve job on the head along with new valves (the rest will probably be salvaged/repaired).

Except the cam. This is where I'm going to need your help, I need an aggressive cam, something lopey and powerful in the 4-6k range preferrably. The majority of this project for the time being will just be head work/exhaust/intake. I will still be keeping carb, and going with a weber. Fuel pump etc will remain stock for now.

In the end I will have a fully rebuilt engine, but for now, this is the best time to start working on head work. I still need the car as a daily driver so I can get a head from a wrecker, along with my custom intake mani and the header back exhaust and build it up. And when the time comes, I'll spend a weekend putting it back together. The compression will be bumped up and I'm hoping I can remain on stock rods/crank (salvaging my own after a rebuild, and balanced crank). But I'm getting off topic, the information I am needing right now is:

Cam specs (custom grind would be best) for a fairly lopey idle and strong power peaking below 6000. OEM replacement/regrind is not an option, I want a new cam.
And if anyone knows what the head flows stock would be helpful for some math homework I'd like to do with this.

Would a honda replacement head gasket be fine under raised compression? I'm not planning on going too crazy with it, but a fair increase. Havent checked around too much with different pistons or anything, but thats not my main concern right now. Decking the head will add 1/3:1 C/R typically from my own experience, so thats not quite enough :p.

I wont be running any boost of any kind, strictly NA engine. (By the way, what have you fully built carb'd guys gotten approx? Not looking for anything to compare it too, but I'm hoping to see 20-25 from headwork/exhaust/intake. Maybe overexpecting, but thats about what I got off of a chevette, 1.6(?)l engine. Though that was a project and a half with an 8 valve engine.

[shepherd79]

here are the few tips you need to keep in mind or think about it:
1. too much of Port on the head can actually reduce your power. so don't go nuts on it.
2. since you are going to make custom intake, you may as well go with 2DCOE weber carbs. it will still need a new manifold but it will give you a bigger punch later.
3. what is wrong with regrind cams? a lot of people have them on this board and no one had any problems with them. I had mine from Delta cams. it was 272 grind. power range from 3K to redline. they had bigger cam, that has power range from 4k and up. the problem with that cam is that you can't drive it everyday. well you can, but i don't think you want to rev it just to get some power. there are some other companies that make nice grinds. there is nothing wrong with them as long as they made correctly.

[smufguy]

port and polish is the main part of the head that will mark the limit of ur head flow. If the ports are not smooth and the angles are too sharp....... you know the result. You can get a good port and polish done by a good local shop cause they have a good experience with pnp. Get yourself another spare head so if u ever fuck up, u will have a spare one to move on rather than hunt one down again.

Running efi would be better for you since you will have a lot of options later on to up the power. if you are gonna run efi. check this thread out about intake manifolds. (http://www.3geez.com/showthread.php?t=42065)

if you want 25hp more is not that hard to get outta ur motor. u can still build ur A1 motor to A3 specs and still end up with 120hp or more with your pnp. WHich is the compression ratio of 9.3, stock efi cams and valves. But if ur expecting more than 120 hp. THen here is what you can do. get the valve train build up using a carb head. With the carb valves and then use the stock efi camshaft, and get it reground to stage 2. I think Jimmy had colt cams. They have pretty crazy lifts for which jim had, his stage 3 had .400+ lift. And for you stage 2 is good. u can given them your power band requirement, and ur redline and they will regrind your camshaft for those specs.
NOTE: No one makes brand new performance camshaft for our cars. Regrind is your only option. Only the newer F, H and B series have companies that make brand new performance Camshafts.

as for the topic of compression. I wont recommend anything more than 10:1 cr for a daily use and fitting ur budget in running the motor. Anything more will make u run premium gas and u dont wanna be using that since its cost is high. 10:1 is the average compression on the V6 accords and they run regular fuel and so u can use it too. Then u also have to get the stock rods sent in, shot peened and sharp angles smoothed out and probably they will balance it. Dont forget to tell the piston manufacturer about ur stock wrist pin size.

I highly suggest that u run efi since u can advance ur ignition, bump the fuel and run colder plugs and pick up as much as 5 hp on a good motor with no modification.

IMPORTANT: search the forum for more information on the numerous "motor build up" threads. u will have a lot of information u are looking for.

[HondaBoy]

i had planned to get a cylinder head off a car at the junk yard for this summer. havent had luck finding a good head though. i was going to get a carbed head and then try finding an efi head. i'd either pull the cam out of it or take the whole head. i just found out that i can do the weber carb without doing modifications to linkage, so thats something i'm thinking about. i'll probley get a pacesetter header. dont know if i'll have that refinished, they usually peel if they arent armor coated. and if i decided to keep a cat converter, i'll get a high flow 2 3/4 inch in and out put on. my fuel pump is brand new, i think its a little better than the stock original. like they were saying if its a daily driver, keep the compression down. i'd probley get it up to 10:1 if i decided to do the new piston and rods, but i dont really want to get into the bottom end. i'd expect nice torque increases with what i'm planning on. i still want to keep good fuel mileage, so around 22 mpg. as for the rpm range, you've got it in a good spot. 6500 is just fine. you should have quite a nice jump in the mid range, and stronger top, so reving high doesnt need to be an issue unless your doing some major racing which it doesnt sound like you would want to get into. just a street car. on my top end i have estimated to spend between $2500-$2800. that'd be buying the head and getting it machined with new parts installed including a cam. then the header and carb, possibley a new cat. i still have to worry about getting my transmission done though, mine is kinda shifty. its needing a rebuild.

[FyreDaug]

Is there a diff between the A1 and A3/4 heads?

[smufguy]

Is there a diff between the A1 and A3/4 heads?

the carb head has longer exhaust valves than the efi head. So using the efi (88-89) camshaft which has more lift, almost 200 more than the carb one, u get more opening of the exhaust valve. I have noticed and alex has noticed quite a difference with the carb head with efi camshaft combination.

[FyreDaug]

Well if I get a regrind it doesnt really matter then does it. Hmm...

If thats the only difference can I use a carb cam in the efi head? (just curious) Which head would be better overall?

[smufguy]

well u can use the carb cam on the efi head, but the lift on the carb cam is a lot smaller like i mentioned. So coupled with the shorter exhaust valve, the total lift of the valve (from the head to full extent) will be a lot shorter. Also the duration and overlap on the efi camshaft is a lot better than the carb cam. Besides, u can still use the carb cam and get it reground to your specs (or their available specs). Its all a matter of how much power you want, what compression you run, and the company you choose will calibrate the camshaft you want. Sometimes the power band will be on the loose end, since high power and a broad rev band does not go together hand-in-hand usually. but for your case, the 150hp (lets keep that as a bench mark) will not be hard to achieve. Also, you need to change your ignition system to a better one as in get a blaster coil and what not, and get some fuel flowing to keep everything good with a 155lbs/hr or more pump, press gauge and a regulator.

u can play with the injectors getting the ones outta a prelude or something (if u have them in the junkyard) if not the stock ones might be okay. Unless they start leaking and shit.

PS: Your other step could be converting to OBD-1. This will defenitely give u a big boost in power gain option and sine changing to obd-1 is not really that hard and a good how-to and few members like our mike from openloop and carotman (off my head) having a good in-depth knowledge of these things, its just a matter of you reading it, talking to them and doing it.

[Acid X]

Hey smurfguy, if you look at my thread you'd see that i aws asking about the EFI cam in a carb engine. If i were to get an EFI cam and get it reground, and then put it in my carb'd A1, would i get more power than with a reground A1 cam?

[smufguy]

Hey smurfguy, if you look at my thread you'd see that i aws asking about the EFI cam in a carb engine.

i was replying to FyreDaug not to you (about the carb cam on a efi head).



If i were to get an EFI cam and get it reground, and then put it in my carb'd A1, would i get more power than with a reground A1 cam?

well it wont matter since all the cams will be ground to the same specs. So u cant say will the stage 1 efi cam and stage 1 carb cam from Colt give more power. Cause both the cams will be reground to the same specs and at the end, both the cams will be identical in their specs.

[Acid X]

i was replying to FyreDaug not to you (about the carb cam on a efi head).




well it wont matter since all the cams will be ground to the same specs. So u cant say will the stage 1 efi cam and stage 1 carb cam from Colt give more power. Cause both the cams will be reground to the same specs and at the end, both the cams will be identical in their specs.

Oh i see. Thank you.. Also, i know you werent replying to me. I was trying to let you know what iw as talking about in another thread, in case you got confused or something.

[FyreDaug]

Ok Im considering getting a wrecked car to use for parts, the whole engine would be done then, piece by piece and it would be cheaper. I'll call around tomorrow and find out prices. It will continue being carb, so no injectors obviously. Intake manifold will be home-made and will more than likely hold 1 carb. Why get 2 when I could get 1 big one? Unless I'm missing something with using a 350+ carb... Get one off a v6 or something maybe, I'll check it out and see what I can use. Everything will be some sort of hybrid mix under the hood when Im done.

[A20A1]

I saw your other thread... so which is it, N/A or BLOWN?

[FyreDaug]

Your gonna shoot me for saying this, but an NA engine thats charged.

[smufguy]

.......... an NA engine thats charged.

There can only be one or the other............. It can either be NA or it can be turbo/super charged.

[FyreDaug]

I know there can only be 1 or the other but for some reason I feel the need for R&D for a theory me and a couple friends (1 is a GM mech) came up with. Its basically an engine that was tuned slightly for an NA application with a blower stuck on it

[shepherd79]

it is not going to work, because both setups will require different tunning.
You have to pick which one you want NA or Blown setup.
4 cylinders are not like 8 cylinders where you can clap blower on it and you can do little tunning. you need a lot of tunning with 4 cylinders.

plus don't forget about compressio ratio, if you want NA motor that makes high power you have to go with high compression such as 11:1 if you attach the blower to it, you will blow the shit ouf that motor.
Blown setups require a lot lower compression anywhere between 8:1 to 9:1.
our stock motor can handle 7-8psi with fine tunning. that would bring you around 160hp at the wheels.

[rjudgey]

NO you don't you can still make 200bhp without having High CR pistons i'm using Sealed power pistons which are really crap and have a a low CR ratio 9.1:1 but as my heads chambers are fully flowed and matched to the bores thats dropped the CR even more, but the head and deck have had a slight skim but only for flattening nothing extreme so i reckon it's still well under 9:1 compression and i've got 200bhp with current ET1 engine. Having High CR ratio pistons isn't as critical as to making Bhp as everyone thinks, it's all in the Cam, head and exhaust system, and BTW Rotrex supercharger is the one to get it's like a belt driven turbo seems like it would be easier to fit as it's about the size of an A/C pump.

[rjudgey]

just had a thought, does anyone know the ROD lengths of the B18 and B16 rods? the B18 are shorter than B16 correct? as the B18 is longer stroke, if we used the B16 rods which are longer, then if we machine the edge of the piston away slightly so that it doesn't hit the head chambers wouldn't that give us a kick arse CR ratio? Just a thought? Possible do you think??

[A20A1]

shave the pistons... wouldn't that throw off the balance though?

[smufguy]

well we cant say that the B18 has shorter rod and B16 has longer rods since the crankshafts used in both the engines are different to increase the displacement. if we do use the B16 rods, then not only will it screw with the compression, it will also lower the displacement due to shorter stroke (disp = 4 * (PI * bore^2 / 4 ) * stroke)

shaving the pistons will throw it off balance, but a lot of pistons are not flat top, unless they are extremely high compression and even they have small indentations for the proper flame front and flame propogation. and last thing you want from shaving is creating uneven surface where heat soaking might occur and chances of pre-ignition or detonation will increase.

[rjudgey]

Well the pistons shouldn't be off balance because they should be balanced before being used, and the tops of the pistons normally have a slight raised part, on any high CR piston most have a rasied centre anyway? Although i do agree that a slight dish in the centre helps spread the load of the explosion on the surface of the piston, also the crank is what determines the stroke not the rod, the rods are different lengths due to the stroke of the crank, a B16 and B18 block are both the same length in Bore size, it's just one uses a longer stroke crank thus this will have shorter rods as the longer stroke would push the piston through the head otherwise, the B16 having a shorter stroke needs a longer rod to push the piston to the full height of the cylinder. Anyways just a thought easier to just get JE pistons made i guess!! I thought their was some benefit to having a longer rod? That and the piston would be lighter too, as for pre igntion or detonation if the piston was machined properly should not be an issue.