LS1_PNYTAMR

iTrader: (1)

232/234 .600/600 f14 from futral motorsports.. i was told no, then a buddy told me he would if it were him... so wtf? lol, now im lost.. i was following that install guide to the T, it doesn't say anything about shims or what not.. somebody help me out here

patriot dual spring kit good to .650 lift.. supposedly one of the better ones there is.

Tranzor

shims??? uh no... Patriot Golds come with everything you need. Install seats, seals, springs, retainers, and go. No need for shims.

LS1_PNYTAMR

iTrader: (1)

okay cool.... so what makes a spring or a cam need shims? i mean teh size of the cam right determines if the springs need shims?

GuitsBoy

iTrader: (4)

not exactly, its more likely dependant on the agressiveness of the lobes and how much seat pressure and open pressure it takes to keep the valves in control at all times up to max RPM. Shimming will increase seat and open pressures, however it will bring you closer to coil bind as well.

LS1_PNYTAMR

iTrader: (1)

so how do i find or figure out if i should do this with these springs... the cam is a f14 232/234 on cam motion lobes .. futral motorsports. 114lsa

GuitsBoy

iTrader: (4)

Call, email, or PM candy or allan futral and theyll let you know if you n eed to or not. I asked and I dont need shims with my f-13 using PRCs or patriot golds. I suspect non of the futral cams require shims, but you should ask them to be sure.

DAPSUPRSLO

iTrader: (14)

I would doubt you need them. However, shimming will help them be able to rpm better based on the increased seat and open pressure as indicated previously. It will also move their harmonic break down point higher in the rpm band which enables even more rpm. The only downside is the spring will also wear out faster too (ofcourse unless they are experiencing float without the shims because of not enough pressure or harmonics). Ofcourse you must make sure you have at least .050" before coil bind though.

jrp

iTrader: (16)

you dont need them, the Associated springs (PP and PRC) both have about 140# @ 1.800 install height.

SidewayzOZ

iTrader: (11)

It's more a matter of whether the springs need to be shimmed with that particular cam application than which cams need shims.

Im using Manley Duals and mine had to be shimmed. Never heard of the Patriot or PRC spring kits having to be shimmed for any cam. Usually just Cranes and Manleys that need shims and its all dependent on application.

ArcticZ28

iTrader: (14)

By shims do you mean the washer-type things that come with some of the kits? I'm also interested in this as I will be installing a PRC kit in some new LQ9 heads with a 6.0 iron block 370 forged bottom end and a 244/248 .635/.627 cam.

mrr23

iTrader: (3)

shims are not the same as the spring locators that you put underneath the shims to protect the aluminum head. to determine if you need shims for a particular application, you need to know a few things. first off is the recommended seat pressure and installed height for a particular cam. let's use #140lbs @ 1.800" installed height. now you get the springs that match the needed requirements. the next thing you do is check what the max distance you have on the head. you use the valve, retainer, and valve locks that are going on the head to do this. put the valve in the head, install the lock and retainer to the valve stem. hold it up so the valve is sitting on the seat. now, you measure the distance from the seat pocket to the bottom of the retainer. there are many ways to do this. let's say this distance is 1.850" also, measure the spring seat locator for thickness as it will shorten the total valve spring height as well. let's say, this is .030" thick. subtract that from the total installed height you got from the head. 1.850 - .030 = 1.820" now take that number and subtract it from the recommended installed height of the spring. 1.820 - 1.800 = .020" needed to get the spring to the recommended height for the cam to get the proper seat pressure.

the other scenario would be you get less height needed than what's recommended. say you only measure 1.750" from the head to the bottom of the retainer. there are ways to fix this as well. offset retainers, locks, or cut the seat pockets.

most spring issues come from not installing them to manufacturers specs or wrong applications. i always advocate using all components from the same manufacturer. they designed it, so use it. use a comp cam, use the springs they recommended. use a crane cam, use their springs. so on, and so on. not saying i haven't mixed parts. as i have vinci/crane springs on a stock cam as it is. but, when i do put a cam in. it'll be a vinci/crane.

kenp

iTrader: (9)

There is a micrometer made specifically for measuring valve spring height. That's the easy way to do it. Put the valve seat in place, set the micrometer in place, put the retainer and locks in place and then turn the micrometer to measure the height you will have when the spring is installed. Every spring manufacturer has a spring install height. The two install heights I've seen are 1.75" and 1.80" on the LS1. If you do not install to the correct height you run the risk of having either less spring pressure than the design calls for or more pressure than the design calls for. If you want to do it right you check the spring height and shim and/or get offset retainers if the height is not as specified by the manufacturer. Can you get by w/o doing it? Sure. Clearly, most people do not check the spring height. www.northernautoparts.com sells the micrometer for about $50. You can get it for less on Ebay if you want to go through the bidding process.

ArcticZ28

iTrader: (14)

I'm still confused about what the washers are in the PRC kit though. Are these the shims or the "spring locators" as mrr23 described that go under the shims to protect the head? Maybe they're neither?

TVWilkes

The washers are the spring locators.This also sets the installed height,and protects the aluminum head.

ArcticZ28

iTrader: (14)

Gotcha. So these definitely need to be used. Thanks Terry. Also, did you get my PM?