Hi there...

I am thinking of swapping a 350 engine in to my 87 Camaro.
The car is now a 305 TPI engine and has still the stock engine in the car.
The car has runned about 85,000miles.

The reason why I want the swap is because I want some more power on my car and I have figured out that swapping to a 350 would be a good starting point..

My question is what kind of engine should I buy...I mean, what would be the cheapest way to go?...Should a buy a used 350 engine (L98) and build it up myself?...I now how to put together a engine

Or should I buy a New crate engine for example ZZ4 that is very popular.

Another thing is that I want to use my TPI system because I want to have a engine that is good in performance and also have good fuel efficiency....Need the fuel efficiency here in Norway with the expensive fuel prizes here...


Any ideas??...I need as much tips as possible..I think it is fun to discuss engine's and swap's....Thanks

 

tip#1-get headers and an exhaust system on your 305. that will probably wipeout a good chunk of your budget and you can start saving more money for the 350 later.

 

I already have a 3" catback system so the sound is very nice

I have been thinking of heders also but those are also very expensive...
I mean..I don't want to use too much money on my 305 engine on performance if I am going to change engine anyway...

 

Well the beauty is all the performance stuff you use in the 305 can be used on a 350 for the most part. So headers for a 305 will work on a 350 as well. For a perofmance car with good fuel econmy although expencive i cant think of a better intake than a modified factory style TPI system. Since you already have it that makes it even easier to do. Also with only 85k miles on it i would wait along time befor swapping as the 305s just a baby right now. Again you can always hop up the 305 and reuse the parts on your 350 when the 305 gets alittle more tired out. While your waiting there are other things you can upgrade as well like the rear gearing as a posi differential if you dont have one alread ect. For a motor i would say start with the zz4 its popular and its popular for a reason. Its got great internals with with 4 bolt mains and parts like a forged steel crank and powdered metal rod. A roller cam set up which is a very big plus. Further more it comes with good heads depend on which vertion you get eather factory style l-98s or GM fast burns. For the price if you were to try and put something with that quality together on your own youde spend alot more.

 

Ok..sound good to me actually....I have had a lot of plans on my Camaro but I am not very good to choose one...lol

I was thinking of purchasing some performance parts to my 305 engine..
The engine was originally a carbed engine but I wanted a more fuel economy so I wanted the TPI. And I personal think it looks very nice...
It is a MAF system and since I have a 87 model I have the roller cam.

What kind of performance should I choose for my TPI setup then..
Performance camshaft mayby and some headers??

And mayby some porting around...Intake, heads etc.etc....

Any ideas would be appreciated...

 

Well i think the biggest bang for your buck mod will be the cam. It is by far the smallest cam ive ever seen. In 85 they used a slightly larger cam pushing which helped the motor produce 215 hp when they changed to the smaller cam that number dropped to 190. And thoes are just lame factory cams designed with 80s technology today i saw summit offered a cam that they advertised something like on the 305 cut a whole second off the 0-60! Best part is it wasnt a huge cam or something unstreetable it was just a nice tame street legal cam really goes to show just how bad the factory one is. I was toying around with comp cams free dyno sim and with one of their small cams i think for fuel designed for fuel economy pushed the tpi performance to just over 380 foot pounds of torque at 2500 RPMs and like 280 something hp at like 5k RPMs. So not only would that motor perform pretty well it would get great gas mileage and the torque would be unbelieveable and street legal. Next i would deffinetly do the headers and y pipes i like the hooker 2055s again street legal and preform way better than our cast iron manifolds. For the intake alittle porting wouldnt hurt but another beauty of the 305 is the TPI system was designed specifically for use on the 305. So changing to larger runners ect has little performance gain. On the 350 which needs more air it becomes a restriction and then you want to look into new runners and porting ect. If you did anything i would just touch up the heads or swap them to vortecs although this would require you to get a new base and maby clean up the intake a bit but nothing too crazy as again the system was designed based on the 305s airflow data so getting too crazy with it might actually be detremental to its performance.

 

Ok..Thanks a lot for the great information...You explain it very good so I really appreciate that....I am from Norway so I don't have any parts store nearby so I will buy most of the parts from the US through Ebay or summit...

What excacly do you think would be best to do with my heads?..Port them and change valve springs,retainers etc etc...
Or change to Vortec heads?..What kind of Vortec heads will be good for me??

And about the camshaft..How high can I go with the lift without affecting my idle very drastic??...

 

Well heres my take on heads. Personally i think vortec heads are the greatest thing that ever happend to the small blcok chevy after roller lifter. The reason is the actually changed the angle of the head itself which leads to better flow rates. Again comming back to why vortecs really its much more complicated than just flow numbers. It really gets into what makes a good head a good head vs a bad one. A flow rate is a volume of air that crosses a certant point in a certant period of time as you probably already know but what you might not have guessed is that although 2 heads with identical flow rates specs can have very different charateristics. For example a "bad" head can flow 220 CFMs from a 200 cc runner while another can flow the same amount from a "good" 170 cc runner. Again whats the difference if they both flow the same amounts? Air Velocities. If 2 heads of different volumes flow the same CFM rateing than that means that the head with the smaller volume has to higher air flow velocities. What do higher air flow velocities improve? Better fuel atomisation which leads to better fuel economy and performance as well as som other unforseen advantages. Now this is why vortechs are great. For a given runner size the flow very well better than alot of aftermarket heads of equivalent runner size. Actually the only head i can think of that can compare to a vortech is AFR heads but even that im not sure if they can do as well. Now because i imagin you guys dont have junkyards with a vast supply of them around youll probably want to order them from a company like summit and thell have some good performance orented heads available. So ideally vortecs would be best. However keep in mind youll need to change the intake base for use on the vortec heads as older style intakes will not bolt on to the new vortecs different bolt pattern. No as for the cam more basic cam theory lol. Simply the higher the lift the more performance you will get and the longer the duration the later the rpm your hp and tq peek will occure. So ideally you want as much lift as you can get reasonable with a duration that will put the power in the right power band. In other words its not so much lift as it is duration that determins the streetability of your cam. For this it really depends on the cam itself as its really not quite that simple but for a street performance/economy car no more than 212 degrees duration at .050.

 

Man, you really are very good explaining and giving me theories..And I really appreciate that...It is so much easier to understand the basics when you write like you do. Thanks a lot...

I have been looking for camshaft's and have found a couple of COMP cam choises.

How about theese two:
http://cgi.ebay.com/COMP-CAMS-SBC-26...QQcmdZViewItem

http://cgi.ebay.com/COMP-CAMS-SBC-26...QQcmdZViewItem


I guess the 266 Cam can be a little agresive mayby???

 

Well thoes cams arnt too bad as far as aggessiveness is concerned. If i had to chose between the 2 ide deffinetly say the smaller one but both to me i think are alittle too big. The reason is TPI on a 350 unless well modded really dies off at 4500 RPMs performance wise where as that cam tries to produce power a bit after 4500 RPMs. So what would happen is youde have a bit of a mix match youll have a decent cam with good higher RPM performance while sacraficeing some low end torque but you wont actually build much high end hp because the factory TPI works well in the low RPMs. So it would be like sacraficeing some low end torque and economy without really gaining anything. Now with some good aftermarket runners and stuff then it would seem to be a pretty stout street cam. On a 305 again with supporting mods it would be fine. Although i will warn you alot of people thing sacraficeing something like 25 foot pounds of low end tq is not big deal when compared to the hp gained but people are forgetting that that 25 ft lbs of torque is multiplied by the rear differential and the trans gearing so a 25 foot pound difference at the flywheel can be a 500 ftlb differences at the wheel. The other thing about cams is the longer duration what your really doing is playing with the motors effiency. Now as you probably already know motors have different efficencies at different RPMs and the longer the duration your just shifting its peek efficency higher in the RPMs. This means higher high end hp but in the lower RPMs where you typically cruse you will be at a less efficient point which means less fuel economy less torque ect. lol youll see modding cars is really an art of trying to find a balance between a bunch of different factors lol. Also if you wanted to toy around with cam changes COMP cams offers a free dyno simulator available on their website thats pretty decent. It would allow you to really see a simulated dyno of your build and you can change cams all day to see the effect. Alot cheaper than doing it in the real world lol.