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Nor Cal trail build

10K views 136 replies 9 participants last post by  DEZPERADO 
#1 · (Edited)
Looking to put together a mild trail build this winter that won’t kill my budget. I finally got my Houser XC A arms dialed, Jogaca shocks valved and sprung all around, and the XC master issues worked out. Now going to get into the engine. I’ve never done any internal engine work, but I can’t imagine it being too hard eh?

Where I ride it’s mostly tight trails with a lot of rock. There’s a few spots I hit in Mendocino that are pretty smooth, but for the most part I don’t get to open it up much. Funny enough my only buddy with a quad rides a LoneStar Banshee on all the same trails. To have big HP like him would be great, but this quad will never see a dune or a drag strip, so my primary goal is to keep it snappy down low on the trails and lift those front tires with ease. Need to stay on pump gas.

THE PLAN ———————-

Been looking at HotCams for a while since I won’t have to upgrade springs, but not sure if I should go stage 2 or 3. Everyone says 3, but it seems like everyone also rips the wide open desert or dunes all the time.

I’ve heard dl700 suggest the 11:1 cp many times, but I’m thinking the 11.5:1 might give me a lil more momentum down low with the extra weight.

Possibly a larger throttle body, maybe a +3. Cuervo had them posted for 175 with a 75 core charge on top.

Do I need a new filter with the TB? I am running a Uni 2 stage on a billet adapter that came from previous owner.

That should do it, I considered going larger stroke but it wasn’t worth it to me for the extra money.
SO -

HC3/2 - $180
11:1 or 11.5:1 ~$200
+3 TB - $200 w/shipping for core (on the fence)
OEM head gasket - $40
tool for installing rings - ???

Hopefully I can get some tunes for the build somewhere, no dyno close me.
I am concerned about detonation or other factors, we have no ethanol free gas available in Cali, always about 20% ethanol and highest grade is 91 at the chevron near me. I am close to Sears point Raceway too, but gas is like 13 a gallon over there for the good stuff.

Opinions needed on all this please. Also, who to buy from, and new or used?
 
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#70 ·
Base gaskets typically don't get rtv, or any sealant, and metal/cometic head gaskets do not.
If you are using a composite head gasket, you can use a light coat of aerosol gasket spray on bolt sides.
Torque to yeild bolts obviously work, but head studs provide a stronger and more consistent seal.
 
#73 ·
Shoot I was going to go with new tty bolts because it’s $50 for all 6 head bolts and 4 cylinder bolts. Compared to $100 for 6 head studs alone.
I’m not totally opposed to going with head studs if that’s the most reliable move.
I can’t seem to find cylinder studs, though. Not sure what’s up with that.
 
#75 ·
A warped head can be sanded with a fine grit paper on a Flat surface, to remove a small amount of material.
It can also be milled .010-.040" (ballpark numbers, I'm not sure what the specs/limit is for a 700 head.
The top of the cylinder should also be checked for warpage, although it's not as common to warp as the head is, as the cylinder has more material, and also as result, disapates more heat quicker.
The top of the cases where the cylinder sits should not be an issue.
Never hurts to check it with a straight edge. It's unlikely, but possible it has a casting flaw, or one half was replaced and they don't align perfectly now.
Go for the head studs and a cometic gasket, it should last longer than tty bolts and a composite gasket, especially with higher compression.
 
#76 ·
Stock base gasket has sealant on it where the cases join. Aftermarket base gaskets don't have the sealant, you can put a small amount of silicone sealant on the aftermarket base gasket where the cases join.
 
#77 ·
I thought OEM gaskets were the best for the head? I suppose I’ll go with studs for longevity thanks.
 
#78 ·
Head warpage can be minor to really twisted, like a table with uneven legs. It rocks, but sit on it and it can flatten out but it ain't right. A straight edge and feeler gauges are used to check, or, run across sand paper and look for low spots. Bad warpage is machined flat. I'm gonna have do agree to disagree with post #75^^. Yes, a warped head can be sanded on a perfectly flat surface but not with fine sand paper. If bad, start with a course paper, then I use more of a medium paper around 180 grit on a 1/2in x 2ft. x 2ft piece of glass. Look at the top of the cylinder I sent, you'll see that the sanding scratches are consistent with no voids. If it were warped there would be areas without scratches. The scratches will hold the gasket better from slipping and prevent failure.

I know you have factory head gasket, that has better sealing then Cometic. I've seen to many Cometic gaskets fail, but, I've only been building motors since the '70's. Any base gaskets will work but the factory gasket has the extra sealant added.

Get the head studs, you'll thank me later. Use factory cylinder bolts.
 
#79 ·
Savage thanks again guys.
Bo said the raptor head has a ‘design flaw’, if you will, in that almost every head he’s ever seen is warped corner to corner. He said he takes care of it though so I won’t have to. Thankfully.

Off to the machine shop with my cylinder now. Does anyone know how far down to the bottom of the cylinder the piston rings travel when installed? There are a couple small scratches at the bottom end of this cylinder. Top most scratch is 1&3/8” high off the bottom. That should be fine right, the rings won’t ever travel that low?
 
#81 ·
Off to the machine shop with my cylinder now. Does anyone know how far down to the bottom of the cylinder the piston rings travel when installed? There are a couple small scratches at the bottom end of this cylinder. Top most scratch is 1&3/8” high off the bottom. That should be fine right, the rings won’t ever travel that low?
I don't recall how far the piston goes but I don't think it goes past the bottom of the cylinder. That means the rings are at the top of the piston "X" amount.
Check with your machinist. If it doesn't work out for you, let me know for a return.
 
#80 ·
I was going to crank her over to check bdc but I don’t have the enormous Allen wrench needed to remove the cover yet.
 
#82 ·
While I’m waiting for other parts to arrive in the mail, I’ve been looking at skids. I’m debating between the black poly skid for $100 @1/2” thick or the silver aluminum one for $80 @.125” thick.
Anyone want to weigh in? I like the black, but it looks bulky. The aluminum one weighs 7lbs.


 
#83 ·
I believe when I was looking at them I found poly in 1/2", 3/8" and 1/4" from different brands. If you will never ride areas with rocks the thinner one will work and save a some weight. If I was worried about rocks and protection get the 1/2" DRW. The extra weight of a skid plate is carried at the lowest point on the frame, I don't think you will notice it.
 
#86 ·
Thanks for the tip. Those wings on the side work alright with nerf bars? I’m leaning toward TM Designs poly skid just for the black color. They have the wings too and the guys said I may need to chop em off.
 
#88 ·
I have the gytr and had to notch the wings on both sides for the Tusk nerf bars. I like how the fasteners are recessed in it too. I saw some skidplates where they weren't and was worried the would get sheared off.
 
#90 ·
Interesting alright thanks for the info. I can pull a stock photo but I will take some pics of the skid when I get it too.
It looks like the blue one is for a different model judging by the oil drain cutouts. Black one looks about right.


upload image
 
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#91 ·
Got my new cylinder in yesterday, going to gap the rings today and see if I can get the piston installed after work.
Can anyone tell me what to gap the rings at for an 11:1 cp? I’ve read .020 on first and second ring, but not sure entirely. I know CP gave me a sheet with their specs but I want to see what you veterans have been doing reliably.
 
#92 ·
I try for .018 to .020 for the top ring and .022 to .024 for the second ring. You will be fine at .020 for each ring unless you have nitrous, turbo...
Too tight is bad, when ring gap goes to zero, you wipe out the cylinder and piston.
 
#93 ·
True. Thank you for confirmation.
 
#94 ·
Well, check out these shenanigans -

Had a muffler shop do my O2 bung and the guy completely botched the job. Porosity all over, bottom of threads thrashed, weld looks like a pile of...yeah. At least the sensor I have threads all the way in and seals tight.






SOOOO after that fiasco I headed up to my union hall this morning to get with our shop weld instructor and certifier to ask for his help in the matter.
He’s pretty stoic, so he took the exhaust, silently looked it over for about 10 seconds, peered up over the top of his glasses and asked, “You payed for this?” Pretty embarrassing lol.
He said the guy clearly carbon arc’d the stainless, which is the worst move you could possibly make on stainless, so he ground out what he could and covered it with some 308. Being a union welder he was so irritated the whole time at the scab trash that some shops produce.
Here’s the final product. No more porosity. Had it done in about 5 minutes.


 
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#95 ·
It looked like my wife welded it, before you had it welded again. That guy should have been embarrassed and apologized and gave your money back. I would have cut the hole myself and TIG welded it. Welding takes time and experience to get good at it, especial with different metals. Did you look inside the pipe to ensure it was clean, meaning nothing hanging down to interfere with airflow.
 
#97 ·
It looked like my wife welded it, before you had it welded again. That guy should have been embarrassed and apologized and gave your money back. I would have cut the hole myself and TIG welded it. Welding takes time and experience to get good at it, especial with different metals.
I thought the same, except my wife can lay a pretty good bead. My thought too was how much did he pay you for gobbing up the pipe.
 
#96 ·
edit
 
#98 ·
Yeah I looked at it at the shop and he said, “So I had like a half hour into it, so uh, how about 40 bucks?” I just looked at him and looked at the weld and said...ok. Won’t be going back anytime soon. Left a review on his business’ yelp page. Dude was the owner too, late 60s, super crabby the whole time. Wasn’t going to argue with him, and sure as heck wasn’t going to ask him to fix it.
Nothing hanging down inside either, thankfully.
All is well now at least. Well, except I’m out 40 bucks ?
 
#100 ·
Megladon port +2/+1 with bored TB by Bo White. Rocker is a CNC clearanced Racers Edge rocker arm too. 50/50 cam installed.







man images free
 
#101 ·
Going to install the head this weekend, possibly after work this week. I’m dying to get her up and running, but I may be headed to check out another Raptor first... Ah priorities.
 
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