A ? about siamesing L98 base....
Thread Starter
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 109
From: Austin Texas
A ? about siamesing L98 base....
I'm wondering if anyone has any data on how far in to siamese the runners. I have the motor apart (spun a rod bearing :cry ) and want to see what siamesing the runners will gain me. The motor is being put back together the same as it was before...just has a Canton road-race pan on it this time.
I've seen references from 3/4" up to 1.5", and wanted to know how much is too much to grind on these things.
I plan on putting it back on the dyno to see where I am at once it is running again.
Any help is appreciated...
I've seen references from 3/4" up to 1.5", and wanted to know how much is too much to grind on these things.
I plan on putting it back on the dyno to see where I am at once it is running again.
Any help is appreciated...
Drifting
Joined: Feb 2002
Posts: 1,937
Likes: 2
From: Arvada CO
Re: A ? about siamesing L98 base.... (Joe90)
Well having a blower in my motor the runners have not choice but to cram that air in my car...BUT i heard (TPIS) that the weak link on the L98 is the base the intake manifold...(Big Mouth) they told me word for word...you can have K&N air filter,ported plenum, bigger runners, but if your bottle neck is the intake then dont bother on the rest? So i would go with the big mouth intake then go with siemsed runners and plenum and so from idle to 5500rpm you will pull hard and fast! So thats the rumor?? then again i know a guy that is running a blow on his TA and he is running 11.5's at a mile high that is fast and he was not going over 5300rpm and he had intake runners and plenum and throttle body dont need rpm to go fast...keep that in mind! :D
Safety Car
Joined: Apr 1999
Posts: 4,623
Likes: 2
From: Ohio
Re: A ? about siamesing L98 base.... (Joe90)
Joe, I looked into that pretty closely while having my motor built. AKS Racing is one of the authorities on TPI flow data etc. Aaron does NOT recommend it for non drag cars. He says it does make more hp, but it "kills' the bottom end. So I just installed the SR on top of a fully ported Edlebrock base. I had the Accell base, which off the shelf is better than the Ed unit, but doesn't have the mass above the intake ports to accept the Felpro 1205 manifold gaskets needed when running the AFR heads. You may want to try to contact him on through the Forum.
Thread Starter
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 109
From: Austin Texas
Re: A ? about siamesing L98 base.... (h rocks)
Thanks...I guess I'll just go ahead and smooth the passages on the base with the sanding wheels. When we built this last year, the Accel base was flowed and installed as-is straight from the box. The ports are a little rough, and smoothing them out will improve the airflow a little.
All I don't need is to kill some of my bottom end :D
All I don't need is to kill some of my bottom end :D
