Help me pick a combo

ziembic

ziembic

Donating Member
I have gotten off my rear and started putting my truck back together...err... well paying someone else to get off their rear and put my truck together. The block is at the machine shop getting bored .030 over, 4 bolt treatment, eagle h-beams, cryoed crank, SRP pistons. The plan is to use a set of heavily modified L35 heads and a worked over stock upper and lower. I am about to purchase the Holley fuel injection setup that the JS guys have been raving about. I want to keep AC, and I am planning to use the stock manifolds. I have an 80e that is being put together, with the HD kit. What I have not zeroed in on yet is the cam, turbo, and converter.

The goal above all is to drive this truck. I don't daily drive to work since I work from home, but I want to build this truck like it is a daily driver. A secondary goal is to make the truck fairly peppy. I am thinking somewhere like 400 or 450 at the wheels, but this is just a guess. I like to go fast, but I really want to drive this truck like Dave P drives his. I want to drive it to one of the coffee and cars meets on the west coast just for the hell of it. I am reaching out to the guys that have successfully built these motors and had them last. What cam/turbo and converter do you guys recommend? Thanks in advance.
 
Icarus-54

Icarus-54

Donating Old Member
Re: Help me pick a combo

turbo-pte 6266 dbb
converter-tci breakaway 2600 stall
cam-custom grind 212-214 dur. lift 5-530" lsa 113-114
 
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randy merritt

randy merritt

Donating Member
Re: Help me pick a combo

No LS build anymore?

My build is in my sig, and has served me well. I put down 420 hp to all four wheels on a chassis dyno. We will see if the Holley HP setup will make it even better.
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: Help me pick a combo

I would choose a pte6262 over a 6266 for a driver. The larger 66 exhaust wheel would have the potential for another 10-20hp at the expense of some additional lag. Pte6262 or larger has the potential for 450whp.

As for torque converter stall speed, I would want the smallest stall that you could get away with the. Ball bearing turbo would help. Because their isn't a lot of SyTy owners with each turbo combo, I have done a lot of research on turbo buicks. It seems like we can get away with less 200rpm of stall because of our displacement (4.3 vs 3.8). Higher flowing mods (heads/cam) help a little with spool up as well.

I like the 214/214 .531/.531 115 lobe separation cam I have. (I would do 114 if I had to do it again). I have good idle 700rpm with a 14.0:1 afr. I don't have any experience with any other cams though. I would do something in that range.

One thing to think about in your build is the SRP have been known to collapse at high boost levels. If you going to run high boost all the time you might want to reconsider the pistons. Also I don't know what size your valves are but the 2.02/1.6 on vortecs and l35 often crack long term. You may want to consider stock valve sized Vortec (1.94/1.5) for long term reliability.
 
Quickstop [UK]

Quickstop [UK]

Combating adversyty.
Re: Help me pick a combo

I don't get why you would pay for work on L35s. They are worse than stock vortecs and if you are going to do extra work, why not go vortec first? If you crack a head or anything, all the port work is wasted. Plus, how good can the port work be?

I'd get stock vortec heads, leave the valves alone and run them as is.
 
ziembic

ziembic

Donating Member
Re: Help me pick a combo

dgoodhue said:
I would choose a pte6262 over a 6266 for a driver. The larger 66 exhaust wheel would have the potential for another 10-20hp at the expense of some additional lag. Pte6262 or larger has the potential for 450whp.


One thing to think about in your build is the SRP have been known to collapse at high boost levels. If you going to run high boost all the time you might want to reconsider the pistons. Also I don't know what size your valves are but the 2.02/1.6 on vortecs and l35 often crack long term. You may want to consider stock valve sized Vortec (1.94/1.5) for long term reliability.
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Thanks for your input. Should I be worried too much about spool since it would be ball bearing? The heads that I am getting are 2.0/1.6 for just this reason. What is considered high boost? With this turbo selection, will I need to be high boost for my target levels? Should I convsider staying with the larger turbo to to avoid higher boost with more volume? Hopefully these aren't dumb questions.

Quickstop [UK] said:
I don't get why you would pay for work on L35s. They are worse than stock vortecs and if you are going to do extra work, why not go vortec first? If you crack a head or anything, all the port work is wasted. Plus, how good can the port work be?

I'd get stock vortec heads, leave the valves alone and run them as is.
Click to expand...

I am getting the heads second hand. The person before me did all of the porting. There is a significant amount of time in these heads. I think they will be OK for my application. A lot of the savings in using stock vortecs is lost in all of the modifying of the heads and intake. IMHO
 
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dgoodhue

dgoodhue

BuSTeD 4.3
Re: Help me pick a combo

ziembic said:
Thanks for your input. Should I be worried too much about spool since it would be ball bearing? The heads that I am getting are 2.0/1.6 for just this reason. What is considered high boost? With this turbo selection, will I need to be high boost for my target levels? Should I convsider staying with the larger turbo to to avoid higher boost with more volume? Hopefully these aren't dumb questions.
Click to expand...
I don't think your could get away with a stock stall converter with a PTE6262BB, but a quality 2600rpm stall converter should be fine.

I did a quick search on syty.net, SRP recommends those pistons for 14 psi or less. I found a post by Windedv6

"I talked to J&E about this and found out that our SRP pistons are not designed to take the amount of boost some of us are giving them. They claim that 14# of boost is all that they recommend. I am sure that they are hedging some and we probably won't have problems in the 20# and below range, but I am convinced that these pistons are not for our bigger builds. They have seen a number of collasped skirts on boosted applicated with SRP pistons. Thier recommendation was the go to the J&E turbo piston or a custom full disk for our bigger builds..."


Assuming the turbo used is within its efficiency range, a motor running 14.5psi will approximately double its NA output. (the output might change slightly higher with a larger turbo due the less restrictive exhaust) The key with low boost making HP is have a free flowing engine, obviously this mean better cam, heads and exhaust perhaps better flow intake manifold, exhaust manifolds. As for your engine, I don't know how much boost it will need. The air flow of your heads L35 heads will make a difference. I think on my motor (junkyard vortec with the higher compression/ported vortecs) and 20psi would get me between 400-450whp (definitely over 400 probably not 450) if it held together.
 
Icarus-54

Icarus-54

Donating Old Member
Re: Help me pick a combo

Yes that's the same turbo I'm running now.As for the srp's,I've been running them at 20 psi for the last 5 years with no problems.You'll get much better flow with the 6266 than with the 6262.I run a 2800 stall and could have easily got away with 2-400 less.The ball bearing makes a hellova difference.As far as lag goes there is none.On the plus side,the 6266 is the biggest you can run with 60# injectors.
 
JSM

JSM

Active member
Re: Help me pick a combo

One of the mods i am really starting to like is conversion to a carb style intake, I have not had a back to back test yet with/without one, but everytime I have helped build a motor with one they just worked well for power.
 
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