Ideal internals for FI?

[robyn402]

so this is my goal http://www.youtube.com/watch?v=ImBgojbvd-Y

and now begins the question process

how do you know what compression to use with a FI application?

speciffically i'm planning on going with ripps stage 2 s/c kit, but i would like to build the internals as well.. so i was thinking of forged rods and pistons with lower compression pistons and a FI specific camshaft...

from what limited FI knowledge i know its benificial to run a lower compression piston but how would you know what to go with?

what else is there i could replace when building the engine since i'd have it all apart anyhow

[tsi20gawd]

8.0-9.0 is the "standard" Compression ratio for forced induction applications. Remember with a lower compression ratio you can run slightly more timing and more boost, than a high compression varient.

Bryan

[robyn402]

yea that pretty much the only thing i know about FI mods... is there a way to know if 8 is too low or 9 is too high for your application?

oh i'm looking to have this all up and running for next spring so gives me ample time to do my homework and get everything done properly the first time


as for components what else is there for strengthening the engine?

-head bolts
-pistons
-rods

feel free to add to this list


i'm also planning on having the head, intake manifold and throttle body P&P

and a a 2.5inch exhaust...so downpipe,midpipe,high flow cat and cat back system

i assume upgrading the injectors, fuel rail and fuel pump are all good thigns to do as well

[otter]

IMO, unless you're planning high boost levels, I don't see a reason to venture away from the stock 9.5:1 compression level. Besides your short list (head studs, not bolts), you'll need main studs and new rod bolts.

[RalliDew]

evo fuel rail works but i would not change that until you get all the s/c stuff squared away then start that adventure.

[robyn402]

the evo rail will work with RA engines.. hmm didn't know that

as for internals should i stick to OEM or get forged?

main studs? and rod bolts?

wheres the best source for the studs? head and main

would the bolts come with the forged rods or no?

[tsi20gawd]

It really depends on your goals wich Im sure you have heard a thousand times so far. If you looking for a quick 50-60hp run 5psi on your stock internals but watch your plugs for detonation! Headstuds would be good insurace however without them you would more than likely blow the headgasket than melt a piston, choose your fuse.

Bryan

[robyn402]

well the stage 2 kit is running 12psi but apparently it loses 3psi threw th FMIC so its really running at 15psi :S?

so i guess what i'll be running is 12psi either way its putting down 307 WHP
http://www.youtube.com/watch?v=ImBgojbvd-Y


speaking of plugs i heard running a colder range plug is good for FI

if i was to change to a colder plug how would i go about picking which one?

[otter]

Here's the breakdown for NGK part numbers, it'll help you chooose a plug.
http://www.spark-plugs.co.uk/pages/technical/ngkjpg.htm

[robyn402]

wow good link.. anyway how to know how much colder if at all i should go?

and what metal type should i go for.. pretty sure comes in copper,iridum and platinum... i can't rememeber fully been a long day

[tsi20gawd]

heatrange 7 is common for ngk's in forced induction applications.

Bryan

[robyn402]

thanks guys... what about plug type? just stick with the standard metal think its iridum...

[$MIVEC$]

stock rods are forged and imo proven durable

[robyn402]

stock rods are already forged? good to know... i thought i heard somewhere the rods where the weak poin tin the engine

so if the rods are forged already go with forged 9.5-1 pistons?

so makes the list;

-forged pistons
-rod bolts
-main studs
-head studs
-colder range plugs

since i'll be P&P the head is there better valves and springs to get or just use originals>?

[tsi20gawd]

Standard copper el cheapo Ngks are usually the most common.

Bryan