1988 TC single Holset turbo 5.0/ 4R70W Reply #855 – February 08, 2012, 07:45:52 PM Hey JimI would really enjoy that visit. Yeah you are about 5.5 hours away. Maybe we can meet at the Milan Drag racing this summer. Thats about 2.5 hours for me.Travis Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #856 – February 15, 2012, 06:32:21 AM Looks like new heads next month. I'm thinking to go with Twisted Wedge 170 heads, new pushrods and rocker arms. I should have checked the heads better when I had them off.I can't wait to see how it'll run with good flowing heads. Hopefully the wastegate is up to the flow. Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #857 – February 15, 2012, 12:37:44 PM Are the gt40 heads cracked? Or just a leaky headgasket?TravisP.S. 1997 explorer engine if I remember Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #858 – February 15, 2012, 02:30:48 PM Quote from: turbotrav;380722Are the gt40 heads cracked? Or just a leaky headgasket?TravisP.S. 1997 explorer engine if I rememberI'm thinking there's a cracked head somewhere not obvious. The heads are rebuilt E7's I had because the GT40's plug angle interfered with my flipped headers.I'm going to pressurize the system after I get it torn down to try to pinpoint the leak. It isn't a blown gasket, I am pretty sure of that.I have a spare block here if I need it. I'll want to find smoking gun this time for sure. I'll get the parts here, then tear off the turbo system, upper intake and headers. Then I'll put some pressure on the radiator through a modified cap with an air nipple. Then I'll wait to see if any water comes out or if I can hear any air escaping. Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #859 – February 16, 2012, 07:11:41 AM Dang Jim...good luck with that. What headgasket did you use?Travis Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #860 – February 16, 2012, 09:04:12 AM I think it was 9303 or some similar number. It wasn't cheap.I'll get it fixed, it just is forcing me to do heads sooner is all. Luckily the IRS didn't get me as bad as last year. LOL Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #861 – February 18, 2012, 07:09:00 PM I just pickup a cheap set of 94 Lightning gt40 heads for pretty cheap. I wasn't going to do the heads this year. But lightning heads with the 1/2 head bolt hole are abit more rare. Im going to run a pretty tough gasket myself. I saved the model number awhile back.Travis Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #862 – February 19, 2012, 08:12:47 AM I had a set of P heads here but they didn't work with my turbo headers. Plugs pointed right into the tubes.I'm tending to think that if I get a good clamp it won't matter what gasket I use as much as if the tune is right. Having the 1/2 inch bolts seems a good idea. You can go to 100# on the outer row of head bolts with 1/2". I may drill and tap my block for bigger fasteners when I get the heads. TW heads can be drilled out to the 1/2" size easily I think. Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #863 – February 19, 2012, 10:12:03 AM Hey JimI believe all aftermarket heads can be drilled out to a 1/2". Saves on making two different setups for the 302/351 crowd. I really wonder about the "lack" of clamping force with the stock style heads? After hanging out with many really fast turbo nutz online. I'm really beginning to think the all 302 blocks (except aftermarket performance blocks) flex too much(I realize all blocks flex abit). When the user starts making too much HP with moderate revving or moderate HP with too much revving. The block really starts to flex, the first thing to go is the headgaskets. So the users puts really tough HG(everybody says so!), mega headbolts or studs(everybody says so!), and quality aftermarket head for more HP. Then continues on there quest for more HP and possibly revving. Bottom line the rotating assembly in a 302 way out performs the block. Jim I dont have any personal proof, its just thinking and reading on my part.. The only 5.0 I have ever owned was the SO 5.0 in my 87LX Tbird. One thing I did notice was heavier cars like ours didn't fair as well in the 450+rwhp. Almost always a headgasket 1st then the block if the user keeps up on the boost. That is why I went 351w. So if I where you, I would buy the best HG your money will buy. Whatever head you want! (it will only make it easier to get to the 450rwhp to break the block). Then buy ARP head studs. That should do it. Anyways what do you think?Travis Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #864 – February 19, 2012, 02:44:46 PM Well, I have been hanging over on TurboForums and following guys issues with 5.0's for years bow.For the most part I agree with you. I do wonder if backpressure might be causing problems in the heavier cars more than lighter ones? I am.not convinced that the headgasket itself is much of a concern at 10 - 15 PSI. It does seem that everyone who had a problem lifting iron heads solved it with aftermarket heads. It'll be nice to get my water issue solved so I can get to some real tuning. I haven't done more than a short blast up to now since I know things aren't right.You should be in better shape with the 351 for sure. A friend gave me this engine or I would have one in here now. Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #865 – February 19, 2012, 03:13:40 PM All 302 heads can be drilled to 1/2" The 351s use the same heads as the 302s, the hole are just machined bigger during the finishing process. The late model 302s and 351s use the same E7 castings. Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #866 – February 19, 2012, 10:12:59 PM How is it bubbling? IS it forcing out the coolant or just a bubble or two (trapped air from removing the radiator cap)? Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #867 – February 20, 2012, 08:00:08 PM It's g coolant out constantly. It has since the start. The harder I drive it the more it pukes. In boost or not makes no difference. ERR! Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #868 – February 20, 2012, 08:46:59 PM That totally sucks Jim. So what heads are you going with?Travis Quote Selected
1988 TC single Holset turbo 5.0/ 4R70W Reply #869 – February 25, 2012, 01:11:21 AM wow, just read thru all 80+ pages! I cant wait to get to your stage. I am still screwing around trying to get my interior done! Quote Selected
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