KYL98

I was wondering if somebody could tell me where I could find the stock head flow rates with the stock L98 cam??? I have the specs on the cam, compression, and flow-rates for the Intake....just not the heads. The reason Im asking is Im developing a program at work that is similar to Desktop Dyno...but you dont have to input all the variables....this program will already have that....you just put in what kind of mods and so on. I also need somebody to check my numbers to make sure they are correct. Thanks in advance.


Camshaft
Duration @.050 202/207
Lift (1.5rr) .413/.428
LSA114.5

GM part#10111773

FLow Rates for Intake

Runners 203cfm
Intake manifold 199cfm
Passage length 8in
runner length 11.25in
Length from plenum to valve seat 25.375in

Comp ratio 9.3:1

Thats all I have so far.....I know the rest..such as bore/stroke, rod length, etc. I do know the stock valve sizes(1.94/1.50), but not the CC's or flow rates....if somebody could give me those or show me where I could find them I would greatly appreciate it. I will also keep you posted as far as the program is concerned. THanks again.....

Black 91 Z28

Iron L98s
0.1 53.9 41.6
0.2 111.2 95.2
0.3 157.3 112.4
0.4 182 116.6
0.5 192 116.9
0.6 193.6 117.6


Rhuarc30 posted these numbers in the first part of his series on porting Iron L98s.


David

KYL98

Thanks a bunch....I did a search...but couldnt find it for whatever reason. Im assuming those numbers are with the stock bumpstick.....thanks again.....

Black 91 Z28

The cam doesn't a cylinder head flow test in anyway. The values given are simply how much air (CFM) was sucked through the intake or exhaust at a given valve lift at a certain pressure drop (28" water in this case).

David

KYL98

Ok duh....I dont know why I was thinking that....I really wasnt sure how they did the flow test to be honest. Anyway, the combustion chamber on the iron heads are 64cc right? Thanks again......

Black 91 Z28

No prob. Yes they are 64cc to the best of my knowledge.

David

rhuarc31

If you're interested in the rest of my l98 head project its at
L98 Iron Head Project

KYL98

I actually just checked it out a min ago....very impressive numbers....I didnt know you could get those out of "factory" heads. I might just sell my Sportsman II's and use the old L98 heads......I kinda like cast iron better anyway, they retain more heat, therefore making better HP. Thanks for all the help guys......