Chris_Formula

Hello thirdgen-User,

I finally registered myself in this forum, it is well known in the german forums of course.
I read a lot of threads here and know the factors to deal with but not especially for my requirements and engine so i have to ask here, so lets start:

For my daily driven car, I need a cam with a "good" idle, good mileage and computer controlled compatibility. I just want to gain some torque in the low end and want some more power in the mid range (My car responds well from 1500rpm (which I like) but fall on its face in higher rpms (maybe combo of tpi intake and peanut cam).
I love this car and this engine (305) and just want to build it up a bit, i leave the tpi intake on (i like that torque output)
As far as I know, the lift on the stock 305 heads for tpi (does somebody maybe have the cast number or do I have to take a look at it?) is limited by around 0.470" ? It depends on the individually heads i know, but can this 0.470" be generally said?? I currently have 1.6 roller tip rockers installed and would love to leave them on my heads so the cam should be around 0.435" - 0.440" with 1.5 (If there is no cam like that its sad but not bad). The next point is I still have the HO exhaust manifolds on it for "originally design due to the german laws". At least I swapped my stock t pipe to a better y-pipe #16450, then a high flow cat and a nice dynomax catback. So the cam should also work with the restrictive manifolds. My requirements are important, it shouldn`t have a choppy or real lopy idle, idle quality near stock would be good. Mileage is also important (daily driver).

So I have been looking around a bit (most of the collected infos from here) and I found some cams that should/could fit my requirements but I cant find neiter much infos nor sound clips nor reviews etc.

Number 1 cam, which i like the most from specs and appearence Comp Cams X4258HR
click 1
Number 2 more lift but for tpi specifically: Comp Cams 262HR-12
click 2
Number 3 found today the Crane 104221 grind 2030
click 3
Number 4 TPIS Super L98 Hydraulic Roller Camshaft
click 4

Or maybe just the biggest 5.7 tpi cam alike Gm partnumber 10066049

https://www.rockauto.com/de/moreinfo.php?pk=5576193&cc=1251391&jsn=494


Which of these cams can lead me there without hurting my overall driveability much? Or do you have another cam to recommend for my specs?
I received a custom mail order chip yet and it runs pretty good for my aknowledge, it is also well tuned and in good condition. (75.000 miles)
180-188 psi cranking pressure (warm engine).

If your have a recommendation for me, please also list what I need to change with the cam (gears, stall, AFPR, PROM, distributor gear, springs)

Specs of my car:
1987 Firebird Formula Th700R4
305 tpi roller cam (peanut)
2.77:1 rear end, 1800rpm stall
1.6 roller tip rockers
cold air intake
catback and better flowing y-pipe (still exhaust manifolds though)
slightly ported plenum (still some work to do)


Thanks that you read all till the end!
Greetings from Germany,

Chris

Chris_Formula

Guys? Wrong Thread? Anybody?

Orr89RocZ

iTrader: (20)

NoEmissions84TA

iTrader: (1)

For your reading pleasure:

https://www.thirdgen.org/forums/tech...ml#post5662778

https://www.thirdgen.org/forums/tech...k-lb9-maf.html

https://www.thirdgen.org/forums/tech...arbed-l69.html

https://www.thirdgen.org/forums/tech...cs-affect.html

https://www.thirdgen.org/forums/tech...-camshaft.html

https://www.thirdgen.org/forums/tech...get-305-a.html

Chris_Formula

Thanks dudes for your answers, I will read all those threads.
How's the idling quality of The comp 262? Do I need a AFPR or is a good tune enough? What about the lift of 0.480"? Should it fit to stock guides and retainers?

Orr89RocZ

iTrader: (20)

SilverChicken

iTrader: (1)

Ozz1967

iTrader: (4)

The Lunati 60102 would be a good upgrade from the stock cam without going too overboard. The 60103 is slightly more aggressive but might be too much. I had a 60102 in my 305 and liked how it worked until I upgraded to a 350. It was still a peanut cam comparatively but it was better than stock. Do you need to worry about emissions where you are?

For the exhaust, would an emissions legal header work such as a Hooker 2055 or Dyno-Don set?

Chris_Formula

Thanks for replying!

I do have to worry about emission here and also headers are risky to build in because theyre not stock and requires a registration in the vehicle´s papers, otherwise theyre illegal. So everything that could ruin stock apperance is bad at the moment (The problem is you cant get headers registrated here)

I found the inzy binzy crane 2020 cam today, it looks pretty tiny on the first view but with 1.6 rockers it would be near to the 2030 cam lift but with less duration what keeps my powerband low. (I love low end and wont rev it over 4500) So maybe that cam would be the way to go?? https://www.summitracing.com/int/parts/crn-104211
Pretty much money for that less increase

I already asked summit whether I can use OEM style valvetrain parts for the crane 2020 (I will repleace them all, also springs) but they seem to be not in agreement with each other. Every tech person tell me different storys. So I contacted Crane today and wait for reply.

The Lunati has too much lift for my heads.

So far,
greetings from Germany and happy new year!

Chris_Formula

Hey folk,

after a lot of brainwork I decided to go a mild route and am close to buying a cam.
Either it will be the L98 cam with the specsIn .415 Ex .430 207 213 117.0 LSA

If I remeber correct, it is on a 116 ICL so its 1 degree advanced?

Or it could be the LT1 cam for the B Bodys with specs In .418 Ex.430 191 196 111 LSA

Maybe also the Lunati 20120642 Specs:

Engine Camshaft Model or Series: EFI Compatible
Make: Chevy
Engine: 262-400 SBC
Camshaft Type: Hydraulic Roller
RPM Range: 1500 to 5200 RPM
Intake Valve Lift: .416"
Exhaust Valve Lift: .447"
Advertised Intake Duration: 270°
Advertised Exhaust Duration: 279°
Intake Duration @ .050": 209°
Exhaust Duration @ .050": 213°
Lobe Separation: 112°

Which one will give the best gain down low? I think that would be the LT1 cam for the B-Bodys.
What do I need to modify to make that cam fit? File/cut the dowel pins down to exact length and thats it?

dmccain

iTrader: (2)

Id use that GM# 049 L98 cam. Great torque and wide LSA. That's what I'm using in my TBI 350 engine I'm soon to be dropping in.