hi. I have a 240 gl with a b23e from canada. I want to know what hp I should expect from each of the following mods:

max. timing
ipd hi-flow exhaust
air box mod with k&n
intake hoses from a b21(bigger)
throttle body mods
head porting and polishing
intake maniifold porting and polishing
(matching on exhaust and intake with head)
raising the compression
hotter thermostat

thanks for your help

For 200 to 220 hp, you will need to either swap in a turbo motor or completely rebuild your motor and probably bore it to a 2.3 and perhaps even stroke it. To ask for 80 more hp from a 20 year old motor is not realistic. You might get it briefly. Try nitrous for that. I would start thinking about a swap. Only a very radical 2.3 liter 8V makes 200 to 220 hp. Some 16V get up there. With a turbo it would be easy. Bored/stroked motors can be expensive when purchased and fitted with all the accessories like EMS and bolt on parts. My guess is that a nice Unitek head/cam on a 20 year old B21 would yield more like 160 hp, far from your 200 to 220 hp goal.

Philip Bradley

Well he said he's got a B23E, so it's likely near 140hp stock. 140 was the most made from a naturally aspirated red block. That said, overboring the B23 is probably a bad idea. However, stroking it should be doable with the right crank.. 200hp is possible.. just not cheap.

- alex

In the real world...

max. timing
If your talking about adjusting the timing, then the most you'll gain from that alone would be 0-3kw, depending on what other mods you do.

ipd hi-flow exhaust
Generaly exaust mods get you anywhere from 0-10kw, more if they are combined with other mods. volvo systems actually flow prity good.

air box mod with k&n
Like 0-1kw, generaly it does very little to over all power on most cars.

intake hoses from a b21(bigger)
probally 0kw

throttle body mods
Depends on what you do, maybe 5kw if it's done right.

head porting and polishing
That's prity vague, porting is the black art, anywhere from 0-50kw, depending on the engine and what cam you throw in it, it's possible to get 100% horsepower increases with radical head work.

intake maniifold porting and polishing
Smooths flow, not really a big power gain thing, but makes the engine run better with a smoother torque curve, maybe 1-5kw.

raising the compression
Another vague one, a small raise can get you 5-10kw, anymore and you'll be using high octane fuel and maybe even need regular octane boosters.

hotter thermostat
Not really recomended by most engine tuners, but than it really depends on what country you live in. But there is no power to be gained from this.

well then what do you recommend for hp gains?

For a good rounded engine that will have a bit more punch yet still run nice and get ok fuel economy.

First, make sure it's in a good stage of tune, then probally the following steps.

1. Exaust is a good idea, a quality system with high quality free flowing mufflers will flow better and also allow more mods in the future.

2. playing with timing can be good, power is not allway the aim though, smooth running and having the engine give a bit more punch down low is, a good engine tuner with a degree wheel and some sloted timing belt pullys can really help put the power where you want it, and generaly if it's done right, you will gain some power. But be carefull, if done wrong, you can loose power and make the car less drivable.

3. cam, a mild grind cam shaft is a great way to give a real boost of power, talk to someone about a mild grind, sometimes called a stage one cam, the cam is best done with the timing stuff, and the good part is the head stays on the engine and cost is kept low.
Throttle body mods can be done in this step, but generaly it only usually gives a little power and may not be worth the cost at this stage.

With these things done you'll have a smooth grunty motor, still with good fuel economy and will hold together forever, with gains of up to 25kw or maybe 25%, it goes without saying that good quality components should be used, with new plugs leads etc if needed.

4. this is where it starts to get expensive, this step involves removing the head, a good port and polish, maybe deck the head a bit, which increases the compression and 3 angle valve seats to get better sealing, a big cam is also part of this stage.

5. Finaly here is where you start ripping off the intake and port matching and modifying the throttle body, generaly it's stuff you only do when you searching for the last few kw's of power, as it's kind of pricey for the small gains you generaly get.

After this stage you can have a engine that really pumps, dependign on the compression gain you went for and just how big you went on the porting, maybe 50kw or 50% above stock, using more fuel and putting more of a load on the engine in terms of life span.

6. Go nuts, forged pistons, gapless rings, monster lift cam, custom intake system, you name it, probally good for 100% power gains over stock, but not good for you wallet in terms of fuel bills and the need for much more regular engine servicing.

Generaly it's best to start small and just work to a stage where you like the ballance of power and enonomy.

First off what cylinder head have you got.The good one to get is the 405.Also what cam have you got.The good ones are the K and the H grind
.the 82 had the 405 head with the K grind cam and was good for 136 hp stock.The 83 had a 398 head which is the same as that fitted to the b21a and the 83 b21ft and had the A grind cam as did the b21a.I have a an 82 and an 83 .the 83 has adjustable cam pulley and 2 1,4 inch exhaust system and possiblt 4.1rear end.It feels a little more powerfull than the 82 at the low end.

I have the 136hp mix

I'm just curious as to the intake hoses? what do you mean they are different sizes and what hoses are you looking at? I've got both a B23E and and a B21F in my two cars out front and every hose on the out side looks the same. There are just parts in differnt locations. Please explain. Oh you might get a better respons in the Aftermarket section of this site.

I have the air box mod with K&N filter. Didn't add too much. but made the intake sucking noise louder, probably dropped a tenth of a second on the 0-100KM times. I also have a 2.5 inch free flowing exhaust, made a big differance, I don't have experiance with the IPD system, but I would say go with a full system, headers back, up here in Canada (my location) we don't need cats, so its gone. the entire system probably added 10-15HP from reading of numbers from other people. Another big thing to do would be an electric fan conversion. it will free up some HP and also save the life of your water pump.
I wouldn't raise the compression with out some serious head work, from someone like Unitek. the compression in a B23E is already pretty high and anymore will just casue more hot spots in the head and cause excessive pre detonation.

About hte head P&P, I wouldn't do it my self. You could but make sure you CC the head after to make sure they are all the same. If you got a head from Unitek and all the other mods you've listed I could see maybe 180HP-190HP flywheel power.

You could also lighten the flywheel. Definatly helps out the acceleration, revving, and fuel milage. Your idle will suffer a bit...

Jordan

I would .like to know is your 2 1/2 inch exhaust system 2 1/2 inches at the two down pipes from the exhaust manifold.I have a 2 1/2 inch system from a turnbo car and was thinking about putting it on but may have to replace the rear muffler also.at present I have a Ford Taurus wagon muffler on
( is all stainless and will fit with some slight mods and really cheap,10 dollars canadian).I already have a cam pulley that is advanced 4 degrees or so(home made on this one,after market on the other one)

my intake hoses after the AMM go from a 2-7/8"(?) diameter to a 3/4" diameter and back to 2-7/8". I don't have a cat on my car, my car was purchased in canada and imported here. I am trying to shoot for 200-220hp what should I do to get there? thanks, I used to tune turbo 740's and that MUCH easier. what could I do to make a spare cam gear of mine into an adjustable type?

A machine shop can sometimes slot the original one to allow adjustment, it depends on the design.

it's the type with the two holes, how can I do it