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Port and polish


solid snake
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I really was interested in port and polishing the heads in the near future. I found a very reputable place where they can do it for me, basically they will do a complete rebuilt on the heads with port and polishing. What the guys at the shop told me is that in order for me to really benefit from the p&p that i should go ahead and port the intake manifold. I really want to do this, but I want to find out if this is going to affect my ecu settings cuz of the mod that i want to do. I just want to find ut if there are any side effects to doing this. I already have Thorleys installed, and getting my pathy to breath and fart better with the p&p got me excited to get this mod done. Also, what benefits would I have if I port the TB and the MAF tube, if its even worthwhile. I remember reading a post about a member porting the MAF and got the power button on the tranny to turn on everytime he accelerated, of course i want to avoid this. For right now my pathy is gonna be undriveable until i can get the front suspension fized on her. This is coming first before even doing the P&P.

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Sounds like a good plan to me SS. One thing I wold recommend is that you get compression tests done on all your cylinders too. It would be a shame to port and polish the heads only to have that little bit of extra power lost due to a scored cylinder wall or bad rings. I say this because I had a buddy with a really built older style camaro. He bought new bad-ass heads for it had them installed by A guy in florida who builds race engines and race cars (he pretty much built his camaro up for him too. It wasnt a week later he discovered he had less power than before. It was an automatic with a sweet shift kit on it and it used to be able to break the tires going into 3rd no problem. He couldnt do it at all anymore. So he had to pay the same guy to tear it apart and upon compression testing 2 cylinders failed. I cannot remember exactly why but it had something to do with the rings. Just my .02 SS. Saddest part of all is he got it all fixed and the SOB would run but I think it was like 4 months later either the wing nut or the long bolt itself that holds on the air cleaner rattled off and fell into the motor which in turn destroyed it. He put another engine in, I believe it was a 400 cui long block or something but it was never the same. Sorry for the long post I started to ramble. Let us know how it works out!!

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I did mine in my garage with a die grinder and a P&P Deluxe kit from Standard Abrasives.

Linky

Depending on what the shop will charge and of they're going to flow test them and all, you might want to tackle it yourself since it's really not that difficult and you can do a basic P&P job yourself for about $200 if you already have a compressor. It took prolly 8-10 hrs per head when you total it up, but I wasn't in a big hurry and since I'd never done it before I wanted to take my time.

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Thanks for the replies. I was quoted $200 from the shop down in mexico and $40 for the intake manifold port. At first, I just wanted the P&P, but know that I am thinking of it, I might as well go all out and get a vg33 block and grind out my cams at schnieders. So know that I am doing a vg33 transplant, I want to find out how much of a bigger piston I can install in that block. I can get the engine for may be around $350.00. Man this is turning into a money pit. I figure I at least have 163 hp with the set up I have, after the P&P with the original engine, I may be looking at 170 :shrug:

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Thanks for the replies. I was quoted $200 from the shop down in mexico and $40 for the intake manifold port. At first, I just wanted the P&P, but know that I am thinking of it, I might as well go all out and get a vg33 block and grind out my cams at schnieders. So know that I am doing a vg33 transplant, I want to find out how much of a bigger piston I can install in that block. I can get the engine for may be around $350.00. Man this is turning into a money pit. I figure I at least have 163 hp with the set up I have, after the P&P with the original engine, I may be looking at 170 :shrug:

I'm building a VG33 block at the moment...hitting the odd snag :D

One of the problems is the snout on the VG33 crank is bigger so either you have to turn it down ($$$), use all the pully's from a VG33 (PITA) or (Like I'm trying to do) use a VG30 crank...Same stroke and IIRC same bearing size.

From my searching on the net Some guy's were putting VH45 pistons in VG33's. (With quite a few mods)

 

I'm just waiting for funds :lol:

Edited by TerranoNZ
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I'm building a VG33 block at the moment...hitting the odd snag

One of the problems is the snout on the VG33 crank is bigger

Do you mean the diameter of the 3.3 crank or the length from the face of the block to the end? If the crank snout length is the problem, theres a spacer (Nissan part #12308-V5321) which I used on my newer long snout 3.0 in order to retain the v-belt style pullies from my old short snout 3.0 that might do the trick for you. Dunno if thats what you'd need, but there it is.
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If you're going for every last 1/10 of hp, you want an experienced pro to do the porting along with valve work..

If you're just looking for a noticeable improvement while retaining stock valve sizes, you can do it yourself. I have done several "clean ups" and have always been delighted with the results!

The key is moderation and common sense. Hogging out a lot of material usually results in flow stagnation and loss of power. But if just removing all sharp transitions, gently radiusing sharp corners, and port matching? You can do that and get 80% of the benefits of a full tilt flow benched professional job. Have a machinist do a nice 3 angle valve job and then follow JJ's lead and clean up the ports.

 

Also, many experts do not recommend polishing intake ports anymore. Polish exhausts, but leave a matte finish (fine sanding drum finish) on intakes. This reduces fuel puddling and improves power.

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