Hi there!

I'm from Spain and I had a 1985 Pontiac Trans Am with a LG4 Engine.

I did some ups to increase the car/engine performance, like putting a dual-snorkel from a L69 Camaro on the carburator or changing the entire exhaust system (Hooker headers) to take a bit more HPs.

Now I'm thinking about change the cams for increase the performance. I read some info about it here in ThirdGen, but I have a lot of doubts about what I really need.

Of course I have the stock cams and I read this info someday:

Look at cams in the 210 - 215 degree @ .050" range on the intake, with a larger exhaust lobe. Comp's XE256 and XE262 are known to work well. Crane has cams of somewhat similar specs that also give good results; I think it's the Energizer 272 but I could be wrong. Lunati's new Voodoo series is the right design for this, and may have something in the right duration range for it. Whatever cam you pick, avoid choosing it based on "sound"; any cam that "sounds" "good" will probably be too much for the rest of the engine and car. Replace the valve springs and their hardware, and the timing set, along with the cam. DO NOT try to use a modern cam under stock springs; you'll probably break something.

I usually buy from summitracing.com and I found this parts:

- Comp: http://www.summitracing.com/parts/cc...w/make/pontiac
http://www.summitracing.com/parts/cca-981-16 (Are the springs necessary?)

http://www.summitracing.com/parts/cc...w/make/pontiac

- Lunati: http://www.summitracing.com/parts/lu...w/make/pontiac

- Summit: http://www.summitracing.com/parts/sum-k1102 (I think that in this case don't need to replace the stock valve springs?)
http://www.summitracing.com/parts/cr...8-16/overview/

My higher doubt is about the value of degree @ .050" range and how I could combine items to take all the necessary parts and if it's difficult to do the job... (Done by my mechanic, course)
If someone knows about a make and parts that works fine, I would be very grateful to guide me about it.

And other question.

I have a lot of vibrations in my car (even being stopped) with the car started. I think it comes from the engine or transmission, and I read something about replace the engine mountings. I found this:

http://www.summitracing.com/parts/pr...w/make/pontiac

Any info or idea about it?

Thanks and sorry for my English...

 

This is the Crane Cam that was in my 84 LG4 car. Should have a performer RPM intake or something similar with this cam and for automatics a stall converter is a MUST.

Grind number: 2050
Part Number: 114142
Gross Lift Int: 0.454 - Ext: 0.480
Duration @ 0.050: Int: 216 - Ext: 228
Adv Duration: Int: 272 - Ext: 284
Lobe seperation: 112
RPM range 1800-5600
Emission legal

I really liked this cam and it is a little bit on the wild side.

http://www.summitracing.com/parts/crn-114142/overview/

 

I have to say that my car have manual transmission.

I understand that I dont need the converter?
And for the RPM intake, what is the part I should need? (sorry for my ignorance.)

My mechanic says me about the cams update that, to do it we need to take out the engine and adapt valves and cylinder heads. It's really needed this steps and work?

For this Crane cams, do I need to change the springs and valves?

 

Correct, with a manual transmission you don't have or need a converter. Only for automatics.

Edelbrock Performer RPM intake.

It's not entirely necessary to remove the engine and cylinder heads. I've done it with the motor in the car but the radiator, A/C condenser and the core support bracing had to be removed in order to get the cam in.

You don't need to change valves but depending on how many miles are on the original springs it might be a good idea to install new springs. I'm using my stock springs to keep the seat pressure a little lighter.


Now with that said, there is some benefit of having the valves ground and reconditioning the heads but if you're going that far might as well get new heads with better flow than the stock heads.

If you are thinking that the cam is too aggressive Crane and Comp Cams have a cam with lifts in the 450 range and durations in the 215 range which would be a good alternative as well.

 

Thanks a lot man!

So, I understand that using the stock valves and springs, I only need this parts:
http://www.summitracing.com/parts/crn-114142/overview/
http://www.summitracing.com/int/part...make/chevrolet

Can this upgrade take notable benefits to my car performance? Remember that I already have higher headers and performance exhaust system with the Y-pipe problem solved.

If I decide to change the Springs too, could be this?
http://www.summitracing.com/int/parts/crn-99848-16/
(No idea about the type and measures.)

And, could be adequate getting it with the retainers?
http://www.summitracing.com/int/parts/crn-11308-1

Once again, thanks.
Regards.

 

Correct

Yes, improving the exhaust flow is always a good step in performance upgrade and will benefit the cam upgrade as well.

Those are the springs Crane recommends and they also recommend this retainer kit 99915-16 http://www.summitracing.com/parts/cr...5-16/overview/ and locks 99097 http://www.summitracing.com/parts/crn-99097-1/overview/



Word of warning. New springs should not be installed when the cam is installed. The cam needs to be broke in with weaker springs prior to installing the new springs. Failure to follow Crane's recommended break in procedure will cause the lifters to wipe out the lobes on the cam.

Also read up on the oil additive ZDDP. Manufactures have been reducing the levels of ZDDP in their oil and this was added to protect metal parts from wear especially flat tappet cams. Without this additive your cam and lifters will wear out faster. For the most correct information on this look up Bob The Oil Guy on the internet and his site will fill you in on everything.