Rebuilding my SR need advice

[Grambos13]

I have a redtop SR that is badly in need of a rebuild. Not exactly sure what is wrong with it but it is burning a lot of oil. (pretty sure its valve stem seals) Anyway I have a GT28RS .86 ar turbo everything to support it I just want to know how extensive of a rebuild I should do. I was thinking I would just replace all the bottom end seals/bearings/rings and then spend the majority of my time/money on the head. I am shooting for arround 300RWHP does this sound reasonable or is it worth the extra money to replace the pistons/rods also with better ones? One more thing...What kind of things should I get for my top end? Over all I am going for quality but I would like to save as much money as possible. Any seggestions would be great. Thanks

[PROJECTRB240SX]

The lighter the rotating assembly the more power is free'd up, the less friction on the rotating assembly and valvetrain the more freed power, the less heat a component is subjected too the longer it lasts.

you can get significant gains from reducing friction, shaving weight, reducing heat transfer/containment, and balancing. Granted you will get more gains from head work but you will be able to find more hp locked up in the bottom end.

[Grambos13]

Thanks thats some good advice.

I guess what I am asking is are the stock bottem end internals strong enough to handle 300hp for a good amount of time? And what should I do to my head to help me gain this. I know I want new cams but what cams should I get. I want to keep as much mid range torque as possible. What eles is worth doing to the head?

[180fan]

stock bottom end will handle 300 without breaking a sweat.

Cams won't give you as much in terms of gains as you'd think. Put that money that you'd take from cams and put them into getting a good port and polish job done.

Might want to consider getting a 3 angle valve job. You could also consider a 5 angle valve job, but don't see much of a point of the 5 angle if you're only making about 300 and I'm assuming you want to maintain good streetability.

[Grambos13]

awsome thats the kind of info I'm looking for. What else should I do to the head besides the port/polish/valve job? Should I get aftermarket valves, springs, retainers,...?

[Grambos13]

anyone know where a good place to get a port/polish/3 angle valve job? I'm not sure about just going to a local shop that doesnt know much about the SR

[180fan]

I took my head to a mainly domestic shop but they did an awesome job with the valves. Finding a machinist took some work though, I looked for one that's been around for a while and had their fair share of different motors on their work benches. So I took it to my buddies dad. lol.

Look into replacing valve guides. You can look at bronze-phosphor guides but they can wear down your valves alot faster than oem ones. You can keep the valve train pretty stock if you're keeping stock cams. Maybe new retainers to keep the possibility of valve float a bit lower. Just keep in mind that as you start to strengthen and make everything else stiffer, it increases wear. So don't expect a motor that's got a 5 angle valve job with bronze-phosphor valve guides, stiff valve springs and the works to last as long as a motor that'd be kept at or very close to stock.

[Grambos13]

Is there a place that sells oem valve terrain parts?

[Grambos13]

I wouldn't think reusing the parts would be a good idea but...I'm not too experienced at this kind of stuff. Swapping and installing engines is one thing but rebuilding them I have no experience what so ever. I do have a buddy that is going to help me, just to let you know I'm not just shootin in the dark

[Grambos13]

hehehe train :-)

[PROJECTRB240SX]

I BELIEVE THE SR20DE FOUND IN THE SER'S HAVE THE CORRECT VALVE TRAIN PARTS (GUIDES, VALVES - NOT SODIUM FILLED THOUGH, ETC.).

[180fan]

The exhaust side of the valve guides might work from the KA24DE. The SR20DE's valve guides are 1mm too small for use in the SR20DET. If I'm not mistaken though, valve guides from the Toyota 3S-GTE will work on the exhaust side with some minor modification.

[spider_slayer]

i'm also looking to do a head rebuild soon because i think i blew my headgasket. I was thinking about just a new gasket, studs, port and polish and reflatten the head incase it has warped.

now my question is would it be worth it to start upgrading the valve train with some cams, springs and retainers? i'm sure that the bottom end is fine so i'm not gonna worry about it till i hit around 100k and have some more money to blow.

also: money is a huge issue cause i'm a college student.....

[180fan]

Depends on the budget. If you're a strapped for cash college student like me, ie just makin it, then a port and polish might be out of the question since a good one can cost quite a bit. Don't go cheap on that service, since it can make your motor run like real trash if not shaped right for your specific application.

Cams won't really do too much for your motor if everything else is still stock. If you've got busted valve seals, then I'd probably go ahead and do the rest of the job like springs and retainers, but otherwise, I'd probably keep them stock until something else rolls around that'd justify such a cost with such minimal gains, like a turbo.

So it comes down to your mods, and whether or not you'd be willing to cough up a pretty substantial amount (enough to buy books for at least a quarter/semester) for pretty minimal gains especially if you're planning to rebuild the bottom end later on (you should be able to talk to your machinist to get something discounted if they're rebuilding an entire motor with a p&p). Just my opinion though, it really depends on what you want to do with your cash.

[Grambos13]

would it be a bad idea to re-use the stock guides with say 35-45K on them? It just seems that it is going to be hard to find new oem stockers. Or should I go with the bronze ones and replace the valves with stronger ones?

[180fan]

New valves are gonna cost you a bundle. It's not a bad idea to keep those stock guides and possibly get them reamed to spec especially if you've got a tight budget.

[spider_slayer]

jsut wondering.....when you got your port and polish how much did it cost you? i got $500-$600 to spend on the head and 200 is going to a gasket and studs. so i minght be able to spring for the p&p job.

[180fan]

The p&p job I got didn't cost me much. About 100 for the parts as I did it under supervision of an experienced machinist. He tells me that the normal price if he does it is roughly 700-800 depending on the head.

[spider_slayer]

ouch......... i guess i'll start shopping around. 700 is alot though. thats 70% the cost of a nice new turbo...

[Hijacker]

redtops won't get much out of a P&P job. valve job would be much better

[Grambos13]

are arp head studs re-usable? I was just wondering if I am wasting my money spending another $130 on new ones?

[Grambos13]

Thanks tenkawa for that info...I think I'm just going to go with the 3 angle valve job, some new springs/retainers/,and rocker arm stoppers.

[ca18det_boy]

I have a set of OEM valve stem seals int/exh that I'll sell for $80 shipped.
Modified by ca18det_boy at 10:56 PM 9/3/2005

[180fan]

while you're getting the springs and retainers switched, get a new set of valve stem seals. It will be a very good idea.

[Grambos13]

for sure...i am ordering the the complete engine gasket kit that comes with the seals for $250. Sorrry Ca18 boy

[Neil]

Where u getting the gasket kit from?

[Grambos13]

I beleive enjuku or heavy throttle carries the gasket kit. However I think e-bay is abou $50 cheaper

[Grambos13]

Is it going to be wasted money if I spend $400 on aftermarket springs and retainers if I am leaving prettymuch everything stock in the head?

[Neil]

better springs are for if youre running way high rpm and bigger lift cams. The cams can be rotating so fast that the springs dont have enough force to push the valves back up before the cam lobe comes around again to push it back down. this results in valve float, and munched valves if the SR is an interference engine.

Retainers may not be a bad idea if only for the sake of rebuilding the head.

[Grambos13]

so if I am going to run stock cams is it pretty much pointless to get aftermarket springs? My ecu rev limit is set at 7800 400 up from stock.